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Sample records for brevicauda rodentia cricetidae

  1. New species and records of the mite genus Prolistrophorus (Acariformes: Listrophoridae) from rodents of the subfamily Sigmodontinae (Rodentia: Cricetidae).

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    Bochkov, Andre V; Lareschi, Marcela; Barreto, Mauricio

    2014-10-01

    Six fur-mite species of the genus Prolistrophorus Fain, 1970 (Acariformes: Listrophoridae) were recorded from Central and South American rodents of the subfamily Sigmodontinae (Rodentia: Cricetidae). Among them, Prolistrophorus (Aprolistrophorus) parabidentatus sp. nov. from Akodon azarae from Argentina and Prolistrophorus (Aprolistrophorus) tylomys sp. nov. from Tylomys nudicaudus from Guatemala are described as new for science. New hosts are recorded for the following species: Prolistrophorus (Prolistrophorus) grassii (Radford, 1954) from Zygodontomys brevicauda from Colombia, P. (P.) frontalis (Hirst, 1921) from Oligoryzomys sp. from Argentina, P. (P.) argentinus (Hirst, 1921) from Melanomys caliginosus, Akodon affinis from Colombia and Scapteromys aquaticus from Argentina, Prolistrophorus (Beprolistrophorus) hirstianus Fain, 1973 from Scapteromys aquaticus from Argentina.

  2. Mast cells in the eyes of Calomys callosus(Rodentia: Cricetidae) infected by Toxoplasma gondii.

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    Gil, Cristiane D; Mineo, José R; Smith, Ricardo L; Oliani, Sonia M

    2002-06-01

    The mast cell is a powerful effector cell for the innate immune system, acting through the secretion of several distinct mediators. Few studies have demonstrated the relationship between mast cells and toxoplasmosis. In this study, mast cells were investigated in two experimental Toxoplasma infections using Calomys callosus (Rodentia: Cricetidae) as the host. Animals were inoculated either intraperitoneally or via the conjunctiva with tachyzoites of Toxoplasma gondii (RH strain) and sacrificed after 5 days or 24 h, respectively. Enucleated eyes were processed for histological and ultrastructural analysis. Neither experimental infection altered the localization of mast cells compared to control eyes, but they did lead to an accumulation in some tissues as well as to their activation. There was a significant increase in the number of mast cells within 5 days and 24 h after infection. The ocular lesions were characterized by the presence of tachyzoites, inflammatory cells and vasodilatation in the iris and retina. In conclusion, mast cells were mobilized in these experimental infections, suggesting that they play an important role in the host inflammatory response after infection with T. gondii.

  3. The tubular compartment and the spermatogenic dynamics of the wild rodent Oxymycterus nasutus (Rodentia: Cricetidae).

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    Morais, Ana Carolina Torre; Balarini, Maytê Koch; Lopes, Elizabeth Oliveira; Menezes, Tatiana Prata; Quintela, Fernando Marques; Morais, Danielle Barbosa; Gomes, Marcos de Lucca M; Matta, Sérgio Luis P da

    2014-10-01

    Despite the order Rodentia present worldwide distribution and large number of species in the Brazilian fauna, detailed studies on testicular morphophysiology are still scarce. Therefore, this study aimed to analyze the dynamics of the spermatogenic process of Oxymycterus nasutus using morphometrical and stereological tools. Testicles from ten sexually mature males were used, showing a gonadosomatic index of 0.89%. The testicular parenchyma showed one of the highest tubulesomatic indexes reported among wild rodents - 0.82% - from which 65.12% was allocated into seminiferous epithelium. The average tubular diameter was 249.89 μm, whereas the epithelium height was 62.47 μm and the total length was 18.62 m per gram of testis. Eight different stages of the seminiferous epithelium cycle were described. Stage 1 was used for counting the germ cell population as well as the Sertoli cells. On average, 3.47 type-A spermatogonia, 24.39 primary spermatocytes in preleptotene/leptotene, 24.13 primary spermatocytes in pachytene, 68.38 round spermatids and 7.33 Sertoli cells were found per tubular cross section. There were 91.02 × 10(6) Sertoli cells per gram of testis and each cell was able to support 9.33 spermatids and 16.43 germ cells. The coefficient of spermatogonial mitosis was 7.02, while 2.83 spermatids were produced for each primary spermatocyte in pachytene. The overall efficiency of spermatogenesis was 19.70 cells, whereas the sperm reserve per gram of testis totalized 849.63 × 10(6) spermatids. Therefore, the presented data showed that O. nasutus shows a high energetic investment in reproduction, corroborating the findings for other species of the Cricetidae family.

  4. Estudo experimental de Zygodontomys lasiurus (Rodentia-cricetidae com cepas de Trypanosoma cruzi Studies on the experimental infection of Zygodontomys lasiurus (Rodentia-Cricetidae with three strains of Trypanosoma cruzi

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    Monamaris M. Borges

    1983-10-01

    Full Text Available São apresentados resultados em relação a infecção expertmental de Zygodontomys lasiurus (Rodentia-Cricetidae com duas cepas de T. cruzi isoladas de casos humanos, Y e Berenice, e uma isolada de um triatomíneo silvestre, chamada costalimai. Foram realizados estudos em relação a evolução da parasitemia, duração da patência e prepatência da infecção. Com o objetivo de verificar a agressividade e tropismo tissular das cepas de T. cruzi nesta espécie de roedor, foram também realizados estudos histopatológicos. Os resultados obtidos mostraram que os níveis de parasitemias foram baixos para as três cepas estudadas. A patência da infecção variou de 14 a 16 dias nos animais inoculados com a cepa Y, 26 a 29 dias com a Berenice e 9 a 13 dias com a costalimai. O período prepatente variou de 3 a 5 dias nos animais inoculados com a cepa Y, de 2 a 6 dias com a cepa Berenice e de 6 a 8 dias com a costalimai. As três cepas apresentaram em Z. lasiurus, comprometimento nitidamente muscular, provocando reações leves, moderadas e intensas.Studies on the experimental infection of Zygodontomys lasiurus (Rodentia-Cricetidae are presented in the current paper. Three strains of T. cruzi were used in the experiments: two, Y and Berenice, were originated from human infection, while the third one was obtained from natural infection in a wild bug Triatoma costalimai. The evolution of the parasitemia was studied and the prepatent and patent periods determined. The tissular tropism and aggressiveness of the strains of T. cruzi were verified through histopathological studies. Results have shown that the parasitemia was always kept at low levels for all the strains. The prepatent period in the infected rodents varied from: 3 to 6 days in the Y strain; 2 to 6 days in the Berenice strain; 6 to 8 in the costalimai strain. The patent period showed the following duration patterns: 14 to 16 days in the Y strain; 26 to 29 in the Berenice strain and 6 to 8

  5. Una nueva especie del género Hoplopleura Enderlein, 1904 (Anoplura, Hoplopleuridae parásita de Andinomys edax (Rodentia, Cricetidae

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    González, A.

    1996-12-01

    Full Text Available The authors described a new species Hoplopleura zentaensi sp. n. based on specimens collected on Andinomys edax Thomas, l902, from Sierra de Zenta, Jujuy province, Argentina. Descriptions involve the holotype female; three nymphal instar, external architecture of eggs and sites of oviposition, providing differences with its close relative Hoplopleura hirsuta Ferris, l916 and Hoplopleura oxymycteri Ferris, l921. Comments on distribution of these species on their hosts are presented and they are included in the “erratica” group.Describimos en esta contribución a Hoplopleura zentaensi sp. n., a partir de la hembra, sus tres estadios ninfales y las características coriónicas externas del huevo de la referida especie parásita de Andinomys edax Thomas, 1902 (Rodentia, Cricetidae, capturado en Sierra de Zenta, Jujuy, Argentina. Hoplopleura zentaensi sp. n. es afín a Hoplopleura hirsuta Ferris, 1916 y de Hoplopleura oxymycteri Ferris, 1921, integrando junto a estas especies el grupo “erratica”.

  6. Avaliação da eficácia dos tratamentos com a associação de Sulfadiazina, Pirimetamina e Ácido folínico (SPAF), Azitromicina, infusão de Artemisia annua L. e Espiramicina na prevenção da transmissão vertical da toxoplasmose em Calomys callosus (Rodentia: Cricetidae)

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    Costa, Idessania Nazareth da

    2009-01-01

    O objetivo deste trabalho foi verificar a eficácia dos tratamentos com sulfadiazina, pirimetamina e ácido folínico (SPAF) associados, azitromicina, infusão de Artemisia annua e espiramicina na prevenção da transmissão vertical da toxoplasmose em Calomys callosus (Rodentia: Cricetidae). Fêmeas de C. callosus foram oralmente infectadas com 20 cistos de Toxoplasma gondii (cepa ME-49) no dia de detecção da rolha vaginal (primeiro dia de gestação). O tratamento com azitromicina, inf...

  7. Primer registro del ratón colombiano del bosque Chilomys instans (Cricetidae: Rodentia en Cajamarca: actualizando el listado de mamíferos del Perú

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    César E. Medina

    2016-12-01

    Full Text Available El roedor Chilomys instans (Thomasomyini, Cricetidae es una especie común en la comunidad de mamíferos que habita los Andes del Norte en Sudamérica. Aquí presentamos el primer registro de la especie para el Perú, en base a la revisión morfológica de tres ejemplares colectados en el departamento de Cajamarca (Andes del Centro. Se presentan comentarios sobre la taxonomía de C. instans e información sobre su historia natural. La amplia distribución del género Chilomys en los Andes pone de manifiesto la necesidad de realizar la revisión taxonómica de éste género para esclarecer los límites de las especies que la conforman.

  8. Lamotheoxyuris ackerti n. gen., n. comb. (Nematoda: Heteroxynematidae parasite of Neotoma spp. (Rodentia: Muridae Lamotheoxyuris ackerti n. gen., n. comb. (Nematoda: Heteroxynematidae parásito de Neotoma spp. (Rodentia: Muridae

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    JORGE FALCÓN-ORDAZ

    2010-06-01

    Full Text Available On the basis of the revision of the type material of Aspiculuris ackerti Kruidenier & Mehra, 1959, and new specimens collected from Neotoma nelsoni Goldman, 1905 (Rodentia: Cricetidae, in Veracruz, Mexico, we herein to which A. ackerti is transferred as Lamotheoxyuris ackerti This new genus differs from all other genera included in 1 mouth surrounded by six lips; 2 extension of lateral alae describe a new genus (Lamotheoxyuris n. gen., (Kruidener & Mehra, 1959 n. gen., n. comb. Heteroxynematinae by the following main traits: reduced; and 3 lack of caudal alae.Con base en la revisión del material tipo de Aspiculuris ackerti Kruidenier y Mehra, 1959 y de nuevos ejemplares recolectados en Neotoma nelsoni Goldman, 1905 (Rodentia: Cricetidae, en Veracruz, México, se describe un nuevo género (Lamotheoxyuris n. gen., al que A. ackerti es transferido como Lamotheoxyuris ackerti (Kruidener y Mehra, 1959 n. gen., n. comb. Este nuevo género se distingue de todos los demás géneros incluidos en Heteroxynematinae por las siguientes características: 1 presencia de seis labios rodeando la boca; 2 extensión reducida del ala lateral; y 3 carencia de ala caudal.

  9. Modulation of parasitemia and antibody responce to Trypanosoma cruzy by cyclophosphamide in Calomys callosus (Rodentia, Cricetidae)

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    1992-01-01

    Calomys callosus a wild rodent, previously described as harboring Trypanosoma cruzi, has a low susceptibility to infection by this protozoan. Experiments were designed to evaluate the contribution of the immune response to the resistance to T. cruzi infection exhibited by C. calossus. Animals were submitted to injections of high (200 mg/kg body weight) and low (20 mg/kg body weight) doses of cyclophosphamide on days -1 or -1 and +5, and inoculated with 4 x 10³ T. cruzi on day O. Parasitemia, ...

  10. Comportamiento agresivo del macho del ratón de los volcanes Neotomodon alstoni (Rodentia: Cricetidae)

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    Granados, Humberto; Luis, Juana; Agustín CARMONA; Espinosa, Guillermo; Arenas, Teresa

    2015-01-01

    Se estudió el comportamiento agresivo de los machos del ratón de los volcanes, Neotomodon alstoni, con 50 pares de ratones que fueron clasificados como posibles dominantes (O) y subordinados (S) a través del Método de Melzack- Thompson. La agresividad se registró en las combinaciones: O vs. O y S vs. S. Se formaron dos grupos: Grupo 1 con 12 pares de machos O y 13 S, y Grupo Il con JI O y 14 S. En el Grupo I el nivel de agresividad se cuantificó después de una semana de apareamiento y después...

  11. Karyotypic variation in the Andean rodent Phyllotisxanthopygus (Waterhouse, 1837) (Rodentia, Cricetidae, Sigmodontinae).

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    Labaroni, Carolina Alicia; Malleret, Matías Maximiliano; Novillo, Agustina; Ojeda, Agustina; Rodriguez, Daniela; Cuello, Pablo; Ojeda, Ricardo; Dardo Martí; Lanzone, Cecilia

    2014-01-01

    Phyllotisxanthopygus (Waterhouse, 1837) is an Andean rodent endemic to South America. Despite its wide geographical distribution in Argentina, few individuals have been studied on the cytogenetic level and only through conventional staining. In this work, chromosome characterization of Argentine samples of this species was performed using solid staining, C-banding and base-specific fluorochromes. Twenty two specimens were analyzed, collected in the provinces of Jujuy, Catamarca, and the north and south of Mendoza. All studied specimens showed 2n=38, having mostly the bi-armed autosomes, metacentric or submetacentric. Fundamental Number varied between 70 and 72. These changes were due to the presence of chromosome heteromorphisms in individuals from southern Mendoza and Jujuy. C-banding revealed pericentromeric blocks of constitutive heterochromatin in most chromosomes. Acrocentric chromosomes involved in heteromorphisms showed high variation in the amount of heterochromatin within and among populations. Additionally, banding with fluorochromes (DAPI and chromomycin A3) revealed homologous localization of AT and GC rich regions among chromosomes of the different populations analyzed. Comparisons among heteromorphic pairs suggested, however, that the variation might be the result of complex chromosome rearrangements, involving possibly amplifications and/or deletions of heterochromatic segments. These results are in accordance with molecular studies that indicate genetic variability within and among the populations of this taxon.

  12. Chromosomal variation in Argentine populations of Akodon montensis Thomas, 1913 (Rodentia, Cricetidae, Sigmodontinae).

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    Malleret, Matías Maximiliano; Labaroni, Carolina Alicia; García, Gabriela Verónica; Ferro, Juan Martín; Martí, Dardo Andrea; Lanzone, Cecilia

    2016-01-01

    The genus Akodon Meyen, 1833 is one of the most species-rich among sigmodontine rodents and has great chromosome variability. Akodon montensis has a relatively broad distribution in South America, and Argentine populations are located in the southernmost region of its range. Brazilian populations have important chromosomal variability, but cytogenetic data from Argentina are scarce. We performed a chromosome characterization of natural populations of Akodon montensis using conventional staining, C-banding, Ag-NORs and base-specific fluorochromes. A total of 31 specimens from five localities of Misiones Province, in Argentina, were analyzed. The 2n=24 chromosomes was the most frequently observed karyotype. However, five individuals presented 25 chromosomes due to a supernumerary B-chromosome; and one individual had 2n=26 due to one B plus a trisomy for chromosome 11. Additionally, two XY females and two variants of the X chromosomes were found. C-positive centromeric bands occurred in all chromosomes; additional C-bands were observed in some autosomes, the X, Y and B chromosomes. Ag-NORs were observed in five autosomes, and the B chromosome was frequently marked. Fluorochrome banding was similar among karyotypes of the analyzed populations. Comparisons of cytogenetic data among populations of Argentina and Brazil showed the presence of high intraspecific variability in Akodon montensis and some differences among regions.

  13. The cuticular profile of the aristiform hair as a characteristic feature of Abrawayaomys (Rodentia: Cricetidae

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    Tarcísio de Souza Duarte

    2015-08-01

    Full Text Available ABSTRACT The cuticle is the outermost of the three cellular layers of the mammalian hair. It comprises numerous keratinized scales, whose morphology, combined with other microscopic characteristics of the hair, confers characteristic signature traits to various different species. This study aimed to analyze whether the cuticular patterns of the aristiform hair had any signature implications for the two species of the genus Abrawayaomys Cunha & Cruz, 1979. We identified the cuticular profiles of A. ruschi and A. chebezi. Both species have similar hair pattern. The base of the hair shows "irregular waved" scales with smooth and continuous edges, and the apex showed "transversal waved" small-sized scales with continuous and ornamented edges. The middle portion of the hair exhibits different cuticular patterns on different sides of a single hair follicle: "transversal waved" on the dorsal side and "narrow losangled" on the ventral side. This distribution pattern of the cuticular scales is an unprecedented record for any mammal, and it is an important generic feature that allows the identification of single samples, such as those found in predators' gastrointestinal contents. The species in question are considered rare due to the restricted number of specimens deposited in scientific collections. Our findings may contribute to expanding the species' geographic range by making it possible to identify it in various situations. These results highlight the relevance of studies pertaining the identification of the micromorphology of the aristiform hair, which can be used as a tool to accurately identify rodents.

  14. Migratory Movements of Pygmy Blue Whales (Balaenoptera musculus brevicauda) between Australia and Indonesia as Revealed by Satellite Telemetry

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    Double, Michael C.; Virginia Andrews-Goff; Jenner, K. Curt S.; Micheline-Nicole Jenner; Laverick, Sarah M.; Branch, Trevor A; Nicholas J. Gales

    2014-01-01

    In Australian waters during the austral summer, pygmy blue whales (Balaenoptera musculus brevicauda) occur predictably in two distinct feeding areas off western and southern Australia. As with other blue whale subspecies, outside the austral summer their distribution and movements are poorly understood. In order to describe the migratory movements of these whales, we present the satellite telemetry derived movements of eleven individuals tagged off western Australia over two years. Whales wer...

  15. Infecção experimental de Calomys callosus (Rodentia-Cricetidae) com Leishmania donovani chagasi (Laison, 1982) Experimental infection of Calomys callosus (Rodentia-Cricetidae) with Leishmania donovani

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    Mello,Dalva A.; Maria Lucia Teixeira

    1984-01-01

    Foi descrita a infecção experimental em Calomys callosus com uma cepa de Leishmania donovani chagasi de caso humano. Um grupo de 22 roedores foi inoculado por via intraperitoneal com 0,1 ml de um macerado de baço em salina, rico em amastigotas. Esses animais foram sacrificados três meses após as inoculações, tendo sido realizado: cultura "in vitro" em meio acelular (LIT e NNN) e esfregaços, corados pelo Giemsa, de fígado, baço, medula óssea e sangue; cortes histológicos corados com hematoxili...

  16. Infecção experimental de Calomys callosus (Rodentia-Cricetidae com Leishmania donovani chagasi (Laison, 1982 Experimental infection of Calomys callosus (Rodentia-Cricetidae with Leishmania donovani

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    Dalva A. Mello

    1984-08-01

    Full Text Available Foi descrita a infecção experimental em Calomys callosus com uma cepa de Leishmania donovani chagasi de caso humano. Um grupo de 22 roedores foi inoculado por via intraperitoneal com 0,1 ml de um macerado de baço em salina, rico em amastigotas. Esses animais foram sacrificados três meses após as inoculações, tendo sido realizado: cultura "in vitro" em meio acelular (LIT e NNN e esfregaços, corados pelo Giemsa, de fígado, baço, medula óssea e sangue; cortes histológicos corados com hematoxilina-eosina de fígado e baço. Os resultados para fígado e baço foram: 67% de positividade nas culturas "in vitro"; esfregaços ricos em amastigotas intra e extra celular (inclui medula óssea; reações teciduais traduzidas por hepatomegalia com proliferação das células de Kupffer; reação granulomatosa das áreas portais, esplenomegalia com reações granulomatosas, abundância de formas amastigotas. Os resultados para o sangue foram negativos em todas as investigações.In the current paper experimental infection of Calomys callosus with Leishmania donovani is reported for the first time. A group of 22 C. callosus aged 20 months and weighing 25 g were inoculated with 0.1 of a homogeneous saline preparation of infected spleens of homologous animals. The L. donovani strain used in the experiments was isolated from a case of human visceral leishmaniasis from the state of Maranhão, Brazil. The animals infected were weighed and killed 3 months after the experimental infection. Spleens and livers were also weighed and pieces from them were fixed in 10% formaline and stained with hematoxilin-eosin for histological studies. Impression smears stained with Giemsa were made and cultivation "in vitro" (NNN and LIT was done, with material from blood, spleen, liver and bone marrow. At the end of the experiments the animals showed low of body weight. Splenomegaly was observed in all the inoculated animals. The "in vitro" cultures were positive from liver and spleen in 67% of the animals. Many extracellular and intracellular amastigote forms were seen in the smears of spleen, liver and bone marrow. Blood showed negative results. Histological studies of the liver showed proliferation of Kupffer cells and granulomatous reaction in the portal areas with multinucleated cells and amastigote forms of the parasites. Loss of folicular pattern with parasitism in great numbers of cells around which there were granulomatous reactions were observed in the spleen.

  17. Modulation of parasitemia and antibody responce to Trypanosoma cruzy by cyclophosphamide in Calomys callosus (Rodentia, Cricetidae Modulação da parasitemia e da resposta de anticorpos ao Trypanosoma cruzi pela ciclofosfamida em Calomys callosus (Rodentia, Cricetidae

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    Monamaris Marques Borges

    1992-02-01

    Full Text Available Calomys callosus a wild rodent, previously described as harboring Trypanosoma cruzi, has a low susceptibility to infection by this protozoan. Experiments were designed to evaluate the contribution of the immune response to the resistance to T. cruzi infection exhibited by C. calossus. Animals were submitted to injections of high (200 mg/kg body weight and low (20 mg/kg body weight doses of cyclophosphamide on days -1 or -1 and +5, and inoculated with 4 x 10³ T. cruzi on day O. Parasitemia, mortality and antibody response as measured by direct agglutination of trypomastigotes were observed. Two hundred mg doses of cyclophosphamide resulted in higher parasitemia and mortality as well as in suppression of the antibody response. A single dose of 20 mg enhanced antibody levels on the 20th day after infection, while an additional dose did not further increase antibody production. Parasitemia levels were not depressed, but rather increased in both these groups as compared to untreated controls. Passive transfer of hyperimmune C. callosus anti-T. cruzi serum to cyclophosphamide immunosuppressed animals resulted in lower parasitemia and mortality rates. These results indicate that the immune response plays an important role in the resistance of C. callossus to T. cruzi.Calomys-callosus, roedor silvestre, que já foi encontrado naturalmente infectado pelo Trypanosoma cruzi, tem baixa suscetibilidade à infecção experimental por este protozoário. Foram feitos experimentos para avaliar a contribuição da resposta imune a essa baixa suscetibilidade. Animais foram submetidos a injeção de doses altas (200 mg/kg peso corporal ou doses baixas (20 mg/kg peso corporal de ciclofosfamida nos dias -1 ou -1 e +5, e inoculados com 4 x 10³ T. cruzi no dia O. Observou-se a curva de parasitemia, mortalidade e resposta de anticorpos medida por aglutinação direta de tripomastigotas. Doses de 200 mg resultaram em parasitemia e mortalidade mais elevada e supressão da resposta de anticorpos. Uma dose de 20 mg aumentou os níveis de anticorpos no 20º dia após a infecção, enquanto a administração de uma segunda dose não alterou significativamente a produção de anticorpos. Os níveis de parasitemia não diminuíram, mas pelo contrário, elevaram-se em relação aos animais testemunhos, em ambos os grupos. A transferência passiva de soro anti-T. cruzi de C. callosus resultou em parasitemia e mortalidade mais baixa nos animais imunossuprimidos. Estes resultados indicam que a resposta imune é um importante fator na resistência de C. callosus à infecção por T. cruzi.

  18. Infecção natural do Holochilus brasiliensis nanus Thomas, 1897 (Rodentia, cricetidae por Litomosoides carinii Natural infection of Holochilius brasiliensis nanus Thomas, 1897 (Rodentia, Cricetidae by Litomosoides carinii

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    J. C. Holanda

    1985-03-01

    Full Text Available É registrada a infecção natural do Holochilus brasiliensis nanus, um pequeno roedor semi-aquático da Baixada Ocidental do Estado do Maranhão, Brasil, por Litomosoides carinii.It is recorded the natural infection of Holochilus brasiliensis nanus, a small semi-aquatic rodent of the Occidental Lowland of Maranhão State, Brazil, by Litomosoides carinii.

  19. Descriptive morphometry and stereology of the tubular compartment in the wild rodent Hylaeamys megacephalus (Rodentia: Cricetidae) from Central Brazil.

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    de Melo, Fabiana Cristina Silveira Alves; de Sousa, Tatiane Pires; Costa, Kyvia Lugate C; da Matta, Sérgio Luis P; de Melo, Fabiano Rodrigues; Santa-Rita, Ricardo de Mattos

    2013-04-01

    Information on reproductive characteristics of wild rodents is scarce in the literature. This study aimed to assess the testis morphometry and stereology of Hylaeamys megacephalus. We used five animals in the study, captured in forest fragments in southwestern Goias State, between April and August 2009. The testes were fixed in Karnovsky solution, dehydrated, and embedded in methacrylate. Two-micrometer-thick sections from each sample were stained with toluidine blue/sodium borate 1%. Images of the testicular parenchyma were obtained from photomicroscope and morphometric and stereological analyses were carried out using the Image Pro-Plus software. The average body weight observed in the specimens of H. megacephalus in the study was 47.84 g, of which, 0.40% is allocated to the gonads (GSI) and 0.36% to the seminiferous tubules (TSI). These parameters suggest promiscuous reproductive behavior, of the polyandrous type, favoring males with higher sperm production and consequently, larger testes. The volume density of the seminiferous tubules was 94.46%, which represented a volume of 0.18 mL. The volume density and volume of the interstitium were 5.54% and 0.011 mL, respectively. The diameter of the seminiferous tubules was 206.5 μm and the height of seminiferous epithelium was 71.27 μm. H. megacephalus presents 5.06 m of seminiferous tubules and an average of 27.96 m of seminiferous tubules per gram of testis. The mitotic and meiotic indexes showed losses of 85 and 42%, respectively and an overall loss of 90% over the full spermatogenic process. The number of Sertoli cells per testis and per gram of testis was 7.8×10(6) and 95.28×10(6), respectively. Most of the morphometric parameters evaluated in H. megacephalus in this study are within the range of values described for most mammals.

  20. Comparison between Oligoryzomys nigripes and O. flavescens by RAPD and genetic diversity in O. nigripes (Rodentia, Cricetidae

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    AJ Mossi

    Full Text Available The genus of Oligoryzomys includes species of small size, morphologically similar, which may impede taxonomic identification, mainly between O. flavescens (Waterhouse, 1837 and O. nigripes (Olfers, 1818. The main objective of this work was to investigate whether the RAPD markers are capable of genetically differentiating the specimens O. nigripes and O. flavescens, coming from Rio Grande do Sul (RS and Santa Catarina (SC states, and also to estimate the genetic variability among populations of O. nigripes, with the Uruguay River as a geographical barrier. For this purpose, samples were collected in fragments of forests situated in the North of RS, at FLONA (Floresta Nacional de Passo Fundo and in fragments from SC, close to the Uruguay River. The karyotyping of two samples for each species was carried out and compared using the RAPD technique together with non- karyotyped individuals. Samples of O. nigripes presented 2n = 62; NA = 82, with submetacentric arms on the largest chromosomes, while samples of O. flavescens showed 2n = 64; NA = 66, with the largest chromosomes presenting acrocentric morphology, making such a result the main difference between the species. The analysis was able to detect two distinct groups, being the first one with karyotyped O. flavescens and the second with karyotyped O. nigripes. Identification afforded 211 loci, among them 181 (85.78% polymorphic. The Jaccard similarity coefficient was in the range of 0.45 to 0.87. The UPGMA and Main Coordinate Analysis techniques demonstrated the existence of heterogeneous genetics among populations, but did not separate them completely in terms of geographical standards, and they are not influenced by the Uruguay River, which did not act as an efficient barrier.

  1. Descripción del postcráneo de Rhipidomys austrinus y Graomys griseoflavus (Rodentia, Cricetidae, Sigmodontinae

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    Luz V. Carrizo

    2011-09-01

    Full Text Available Se describe el esqueleto postcraneal de dos especies de roedores sigmodontinos Rhipidomys austrinus Thomas, 1921 y Graomys griseoflavus (Waterhouse, 1837. Se detalla cada estructura del esqueleto postcraneal sobre la base de la forma, tamaño, superficie y orientación de cada elemento esqueletal. La anatomía postcraneal de estas dos especies muestra caracteres asociados a patrones morfológicos diferentes, vinculados a su modo de locomoción. Es así que R. austrinus exhibe características en varios elementos del postcráneo consistente con una locomoción arborícola, mientras G. griseoflavus muestra atributos en su esqueleto relacionados a una locomoción de tipo terrestre.

  2. Migratory movements of pygmy blue whales (Balaenoptera musculus brevicauda between Australia and Indonesia as revealed by satellite telemetry.

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    Michael C Double

    Full Text Available In Australian waters during the austral summer, pygmy blue whales (Balaenoptera musculus brevicauda occur predictably in two distinct feeding areas off western and southern Australia. As with other blue whale subspecies, outside the austral summer their distribution and movements are poorly understood. In order to describe the migratory movements of these whales, we present the satellite telemetry derived movements of eleven individuals tagged off western Australia over two years. Whales were tracked from between 8 and 308 days covering an average distance of 3,009±892 km (mean ± se; range: 832 km-14,101 km at a rate of 21.94±0.74 km per day (0.09 km-455.80 km/day. Whales were tagged during March and April and ultimately migrated northwards post tag deployment with the exception of a single animal which remained in the vicinity of the Perth Canyon/Naturaliste Plateau for its eight day tracking period. The tagged whales travelled relatively near to the Australian coastline (100.0±1.7 km until reaching a prominent peninsula in the north-west of the state of Western Australia (North West Cape after which they travelled offshore (238.0±13.9 km. Whales reached the northern terminus of their migration and potential breeding grounds in Indonesian waters by June. One satellite tag relayed intermittent information to describe aspects of the southern migration from Indonesia with the animal departing around September to arrive in the subtropical frontal zone, south of western Australia in December. Throughout their migratory range, these whales are exposed to impacts associated with industry, fishing and vessel traffic. These movements therefore provide a valuable tool to industry when assessing potential interactions with pygmy blue whales and should be considered by conservation managers and regulators when mitigating impacts of development. This is particularly relevant for this species as it continues to recover from past exploitation.

  3. Migratory movements of pygmy blue whales (Balaenoptera musculus brevicauda) between Australia and Indonesia as revealed by satellite telemetry.

    Science.gov (United States)

    Double, Michael C; Andrews-Goff, Virginia; Jenner, K Curt S; Jenner, Micheline-Nicole; Laverick, Sarah M; Branch, Trevor A; Gales, Nicholas J

    2014-01-01

    In Australian waters during the austral summer, pygmy blue whales (Balaenoptera musculus brevicauda) occur predictably in two distinct feeding areas off western and southern Australia. As with other blue whale subspecies, outside the austral summer their distribution and movements are poorly understood. In order to describe the migratory movements of these whales, we present the satellite telemetry derived movements of eleven individuals tagged off western Australia over two years. Whales were tracked from between 8 and 308 days covering an average distance of 3,009±892 km (mean ± se; range: 832 km-14,101 km) at a rate of 21.94±0.74 km per day (0.09 km-455.80 km/day). Whales were tagged during March and April and ultimately migrated northwards post tag deployment with the exception of a single animal which remained in the vicinity of the Perth Canyon/Naturaliste Plateau for its eight day tracking period. The tagged whales travelled relatively near to the Australian coastline (100.0±1.7 km) until reaching a prominent peninsula in the north-west of the state of Western Australia (North West Cape) after which they travelled offshore (238.0±13.9 km). Whales reached the northern terminus of their migration and potential breeding grounds in Indonesian waters by June. One satellite tag relayed intermittent information to describe aspects of the southern migration from Indonesia with the animal departing around September to arrive in the subtropical frontal zone, south of western Australia in December. Throughout their migratory range, these whales are exposed to impacts associated with industry, fishing and vessel traffic. These movements therefore provide a valuable tool to industry when assessing potential interactions with pygmy blue whales and should be considered by conservation managers and regulators when mitigating impacts of development. This is particularly relevant for this species as it continues to recover from past exploitation.

  4. Pterygodermatites (Paucipectines baiomydis n. sp. (Nematoda: Rictulariidae, a parasite of Baiomys taylori (Cricetidae

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    Lynggaard Christina

    2014-01-01

    Full Text Available Pterygodermatites (Paucipectines baiomydis n. sp., an intestinal parasite of the northern pygmy mouse, Baiomys taylori (Cricetidae, collected in La Yerbabuena, Colima, Mexico, is described herein. Specimens were studied using light and scanning electronic microscopy. This is the 19th species of the subgenus Paucipectines described worldwide and the fourth collected in Mexico. It is differentiated from the remaining species in the subgenus by having 25 perioral denticles, arranged in a triangle (seven on each lateroventral margin, and eleven on the dorsal margin, and 10 pairs of caudal papillae.

  5. Sinobatis brevicauda n. sp., a new deep-water legskate (Rajiformes, Anacanthobatidae) and first generic record from the western Indian Ocean.

    Science.gov (United States)

    Weigmann, Simon; Stehmann, Matthias F W

    2016-07-13

    A new deep-water legskate, Sinobatis brevicauda, is described based on two specimens caught on the remote Saya de Malha Bank in the central western Indian Ocean. The new species is easily distinguished from all other described anacanthobatids by the short tail. It is the only Sinobatis species described from the western Indian Ocean and differs from the other anacanthobatid legskates in this area by its large size and light coloration. All other species of Sinobatis are described from the eastern Indian and, particularly, western Pacific oceans. In addition to the short tail, the new species clearly differs from its morphologically closest congener, the Australian S. bulbicauda, in a bicolored white and grayish ventral coloration with gray and white blotches (vs. uniformly pale or white and skin somewhat translucent) and a filamentous tail without flattened, bulbous tip. Furthermore, it is distinguished by several morphometric and meristic differences, e.g. a longer body (length 65% TL vs. 39-61% TL), longer head (dorsal length 34% TL vs. 21-31% TL, ventral length 41% TL vs. 23-36% TL), longer snout (preorbital length 28-29% TL vs. 14-26% TL, preoral length 30% TL vs. 16-28% TL, prenasal length 28% TL vs. 14-25% TL), and fewer diplospondylous (102-112 vs. 121-142) and total (131-141 vs. 148-168) vertebrae. S. brevicauda clearly differs from the other anacanthobatids in the western Indian Ocean, Anacanthobatis marmorata and Indobatis ori, by having a much shorter tail, strongly different coloration, much larger size, and in many morphometric and meristic differences.

  6. Muridae (Rodentia) from the lower Turolian of Crevillente (Alicante, Spain)

    NARCIS (Netherlands)

    Martín Suárez, E.; Freudenthal, M.

    1993-01-01

    The fauna of Muridae (Rodentia) from the Lower Turolian of Crevillente (Alicante, SE Spain) contains species attributed to the genera Huerzelerimys, Parapodemus, and Occitanomys. The material described allows a detailed biostratigraphy of Upper Miocene deposits of SE Spain. En este trabajo se estudi

  7. Late Miocene Sciuridae (Mammalia, Rodentia) from Anatolia, Turkey

    NARCIS (Netherlands)

    Bosma, A.A.; de Bruijn, H.; Wessels, W.

    2013-01-01

    Isolated cheek teeth of Sciuridae (Rodentia, Mammalia) from nine late Miocene localities in central Anatolia (Turkey) are described. The teeth represent at least 12 different species, five of which belong to the ground squirrel genus Tamias, two to the ground squirrel genus Spermophilinus, one to th

  8. Pulgas (Siphonaptera parásitas de roedores (Rodentia: Cricetidae de la provincia de Salta, Argentina: nuevos registros de distribución

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    M. Fernanda LÓPEZ BERRIZBEITIA

    2013-01-01

    Full Text Available Se mencionan nuevos registros de distribución geográfica y hospeda - toria para pulgas parásitas de roedores sigmodontinos de la provincia de Salta, Ar - gentina. Se reportan por primera vez en Salta las siguientes especies: Craneopsylla minerva minerva (Rothschild; Agastopsylla pearsoni Traub; y Neotyphloceras cras - sispina hemisus Jordan; así como los géneros Cleopsylla Rothschild y Plocopsylla Jordan . Agastopsylla pearsoni se cita por primera vez para la Argentina. También se aumenta el número de especies de parásitos conocidos para cinco especies de roedores y se registran ocho nuevas asociaciones parásito-hospedador.

  9. Infecção experimental de Calomys callosus (Rengger, 1830, (Cricetidae - Rodentia a quatro espécies de parasitos

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    Dalva A. Mello

    1980-12-01

    Full Text Available Neste trabalho foram estudados exemplares do roedor, Calomys callosus, nascidos em laboratório, a infecções experimentais com quatro parasitos: Plasmodium berghei, Leishmania mexicana amazonensis, Schistosoma mansoni e Hymenolepsis nana. A positividade das infecções foi de 80% para os três primeiros parasitos e 0 para H. nana. C. callosus é um roedor de excelente adaptação em laboratório e de fácil manuseio. Acredita-se que, de acordo com os resultados obtidos neste trabalho, este animal poderia ser um bom modelo experimental de laboratório para certos agentes patogênicos.Results of the experimental infections of the iaboratory bred rodent Calomys callosus are presented in th is paper. The following parasites were as infective agents: Plasmodium berghei, Leishmania mexicana amazonensis, Schistosoma mansoni and Hymenolepsis nana. C. callosus was refractory to H. nana while it has shown to be susceptible to the other three parasites. The infection rates for each one this parasites was 80 per cent. C. callosus has been maintained under laboratory conditions for six generations showing excellent adaptation and easy handling. It is believed that this animal can be used as laboratory experimental model for certain parasitic diseases.

  10. Modulação da parasitemia e da resposta de anticorpos ao Trypanosoma cruzi pela ciclofosfamida em Calomys callosus (Rodentia, Cricetidae)

    OpenAIRE

    1992-01-01

    Calomys callosus a wild rodent, previously described as harboring Trypanosoma cruzi, has a low susceptibility to infection by this protozoan. Experiments were designed to evaluate the contribution of the immune response to the resistance to T. cruzi infection exhibited by C. calossus. Animals were submitted to injections of high (200 mg/kg body weight) and low (20 mg/kg body weight) doses of cyclophosphamide on days -1 or -1 and +5, and inoculated with 4 x 10³ T. cruzi on day O. Parasitemia, ...

  11. Infecção experimental de Calomys callosus (Rengger, 1830, (Cricetidae - Rodentia a quatro espécies de parasitos

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    Dalva A. Mello

    1980-12-01

    Full Text Available Neste trabalho foram estudados exemplares do roedor, Calomys callosus, nascidos em laboratório, a infecções experimentais com quatro parasitos: Plasmodium berghei, Leishmania mexicana amazonensis, Schistosoma mansoni e Hymenolepsis nana. A positividade das infecções foi de 80% para os três primeiros parasitos e 0 para H. nana. C. callosus é um roedor de excelente adaptação em laboratório e de fácil manuseio. Acredita-se que, de acordo com os resultados obtidos neste trabalho, este animal poderia ser um bom modelo experimental de laboratório para certos agentes patogênicos.

  12. Efectividad biológica de seis rodenticidas utilizados para el control de Sigmodon hispidus (Rodentia: Cricetidae) en caña de azúcar

    OpenAIRE

    2012-01-01

    Los estudios relacionados con el control químico de la rata algodonera o cañera son escasos, por lo que es difícil tener acceso a la información. Desafortunadamente en México los rodenticidas se aplican con base en recomendaciones generales, por lo que es importante evaluar la efectividad de estos productos en condiciones controladas y de campo. El objetivo en este trabajo fue conocer la efectividad biológica de los rodenticidas: warfarina®, difacinona®, brodifacum®, f...

  13. Chromosome homologies of the highly rearranged karyotypes of four Akodon species (Rodentia, Cricetidae) resolved by reciprocal chromosome painting: the evolution of the lowest diploid number in rodents.

    Science.gov (United States)

    Ventura, Karen; O'Brien, Patricia C M; Yonenaga-Yassuda, Yatiyo; Ferguson-Smith, Malcolm A

    2009-01-01

    Traditionally comparative cytogenetic studies are based mainly on banding patterns. Nevertheless, when dealing with species with highly rearranged genomes, as in Akodon species, or with other highly divergent species, cytogenetic comparisons of banding patterns prove inadequate. Hence, comparative chromosome painting has become the method of choice for genome comparisons at the cytogenetic level since it allows complete chromosome probes of a species to be hybridized in situ onto chromosomes of other species, detecting homologous genomic regions between them. In the present study, we have explored the highly rearranged complements of the Akodon species using reciprocal chromosome painting through species-specific chromosome probes obtained by chromosome sorting. The results revealed complete homology among the complements of Akodon sp. n. (ASP), 2n = 10; Akodon cursor (ACU), 2n = 15; Akodon montensis (AMO), 2n = 24; and Akodon paranaensis (APA), 2n = 44, and extensive chromosome rearrangements have been detected within the species with high precision. Robertsonian and tandem rearrangements, pericentric inversions and/or centromere repositioning, paracentric inversion, translocations, insertions, and breakpoints, where chromosomal rearrangements, seen to be favorable, were observed. Chromosome painting using the APA set of 21 autosomes plus X and Y revealed eight syntenic segments that are shared with A. montensis, A. cursor, and ASP, and one syntenic segment shared by A. montensis and A. cursor plus five exclusive chromosome associations for A. cursor and six for ASP chromosome X, except for the heterochromatin region of ASP X, and even chromosome Y shared complete homology among the species. These data indicate that all those closely related species have experienced a recent extensive process of autosomal rearrangement in which, except for ASP, there is still complete conservation of sex chromosomes homologies.

  14. Ectoparasite occurrence associated with males and females of wild rodents Oligoryzomys flavescens (Waterhouse) and Akodon azarae (Fischer) (Rodentia: Cricetidae: Sigmodontinae) in the Punta Lara wetlands, Argentina.

    Science.gov (United States)

    Lareschi, Marcela

    2010-01-01

    The objective of this research was to study infestation parameters and indexes of ectoparasites associated with each sex of the wild rodents Oligoryzomys flavescens (Waterhouse) andAkodon azarae (Fischer) in the Punta Lara wetlands, Argentina. A trend towards higher mean abundance (MA) and ectoparasite specific richness was observed in males of O. flavescens whereas those values were similar for both A. azarae sexes. The prevalence of the following ectoparasites was significantly higher on males (Prodent hosts, these results are epidemiologically important.

  15. Laelapinae mites (Acari: Parasitiformes: Laelapidae) parasitic of sigmodontine rodents from northern Peru, with the description of a new species from Akodon aerosus (Rodentia: Cricetidae: Sigmodontinae).

    Science.gov (United States)

    Lareschi, Marcela; Velazco, Paúl M

    2013-04-01

    Laelapine mites are common parasites of sigmodontine rodents in the Neotropics. However, few species are reported from Peru as a result of the low number of mammal surveys that include ectoparasite collections. Herein we report 12 species of mites from northern Peru. From these, 8 are reported for the first time for the country, and 1 is new to science , Androlaepaps aerosus sp. nov., the latter associated exclusively with the sigmodontine Akodon aerosus . Most of the laelapine species were host specific. The new species, included in the Androlaelaps rotundus species group, resembles An. rotundus "sensu stricto" and An. ulysespardinasi in general appearance but is unique in the length of the hypostomal seta h3 (>58 μm), which is 3 times as long as the gnathosomal seta, and its tip reaching or over-reaching the gnathosomal setal bases; dorsal seta j2 is very long (>70 μm), almost reaching the point of j3.

  16. Differences in richness and composition of gastrointestinal parasites of small rodents (Cricetidae, Rodentia) in a continental and insular area of the Atlantic Forest in Santa Catarina state, Brazil.

    Science.gov (United States)

    Kuhnen, V V; Graipel, M E; Pinto, C J C

    2012-08-01

    The first and only study on gastrointestinal parasites of wild rodents in the Island of Santa Catarina was done in 1987. The aim of this study was to identify intestinal parasites from wild rodents in Santo Amaro da Imperatriz and Santa Catariana Island, and to compare the richness and composition of the gastrointestinal parasite community of both areas. Rodents were captured with live traps, and feces were screened using the sedimentation method and optical microscopy. The following species of rodents were captured in the two areas: Akodon montensis, Euryoryzomys russatus, Oligoryzomys nigripes and Nectomys squamipes. In Santo Amaro da Impetratriz, prevalent parasites were: A. montensis (51%), E. russatus (62%), O. nigripes (53%) and N. squamipes (20%). From the Island of Santa Catarina the rodent prevalence rates were: A. montensis (43%), E. russatus (59%), O. nigripes (30%) and N. squamipes (33%) and the collected parasites were: Hymenolepis sp., Longistriata sp., Strongyloides sp., Hassalstrongylus sp., Syphacia sp., Trichomonas sp., Ancylostomidae, Trichuridae, Oxyuridae and Eucoccidiorida. The species richness (10.6 ± 0.7) of the endoparasite comunity in the area located on the continent was higher (p < 0.01) and different (p = 0.001) from that of the area located on the island (6.9 ± 0.5).

  17. Chromosomal evolution of Arvicolinae (Cricetidae, Rodentia). I. The genome homology of tundra vole, field vole, mouse and golden hamster revealed by comparative chromosome painting.

    Science.gov (United States)

    Sitnikova, Natalia A; Romanenko, Svetlana A; O'Brien, Patricia C M; Perelman, Polina L; Fu, Beiyuan; Rubtsova, Nadezhda V; Serdukova, Natalya A; Golenishchev, Feodor N; Trifonov, Vladimir A; Ferguson-Smith, Malcolm A; Yang, Fengtang; Graphodatsky, Alexander S

    2007-01-01

    Cross-species chromosome painting has become the mainstay of comparative cytogenetic and chromosome evolution studies. Here we have made a set of chromosomal painting probes for the field vole (Microtus agrestis) by DOP-PCR amplification of flow-sorted chromosomes. Together with painting probes of golden hamster (Mesocricetus auratus) and mouse (Mus musculus), the field vole probes have been hybridized onto the metaphases of the tundra vole (Microtus oeconomus). A comparative chromosome map between these two voles, golden hamster and mouse has been established based on the results of cross-species chromosome painting and G-banding comparisons. The sets of paints from the field vole, golden hamster and mouse identified a total of 27, 40 and 47 homologous autosomal regions, respectively, in the genome of tundra vole; 16, 41 and 51 fusion/fission rearrangements differentiate the karyotype of the tundra vole from the karyotypes of the field vole, golden hamster and mouse, respectively.

  18. Les Cricetidae (Mammalia, Rodentia) du Néogène Moyen de Vieux-Collonges. Partie 2 : Cricetodontinae incertae sedis, Melissiodontinae, Platacanthomyinae, et Anomalomyinae = Cricetidae (Mammalia, Rodentia) of the middle Neogene of Vieux Collonges. France. Part 2 : Cricetodontinae incertae sedis, Melissiodontinae, Platacanthomyinae, et Anomalomyinae

    NARCIS (Netherlands)

    Mein, P.; Freudenthal, M.

    1981-01-01

    Apart from the common cricetid fauna, the site of Vieux-Collonges contains a number of rare forms: Lartetomys, Melissiodon, Neocometes, and Anomalomys. This scarce material is described and compared with material from other European localities. The stratigraphie position of Vieux-Collonges is discus

  19. Acariform mites (Acariformes - permanent symbionts of Hapalomys delacouri Thomas (Rodentia, Muridae in Vietnam

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    Andre Bochkov

    2014-12-01

    Full Text Available Two new species of parasitic acariform mites (Acariformes are described from the Delacour’s marmoset rat Hapalomys delacouri Thomas (Rodentia: Muridae in Vietnam: Afrolistrophorus (Afrolistrophorus hapalomys sp. n. (Listrophoridae and Radfordia (Radfordia mirabilis sp. n. (Myobiidae. Based on morphological evidences, we show that species of both mite genera associated with Hapalomys Blyth do not demonstrate clear phylogenetic links with respective congeners from rodents of the closest genus Chiropodomys Peters (Rodentia: Muridae.

  20. Amphimerus bragai N. Sp. (Digenea: Opisthorchiidae, a Parasite of the Rodent Nectomys squamipes (Cricetidae from Minas Gerais, Brazil

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    Antonio HA de Moraes Neto

    1998-03-01

    Full Text Available Amphimerus bragai n.sp. (Digenea, Opisthorchiidae from the bile ducts of a rodent from the State of Minas Gerais, Brazil, Nectomys squamipes (Cricetidae, is described. The new species was studied by both light and scanning electron microscopy. A table is presented comparing the measurements of the new species with those of A. lancea (Diesing, 1850 and A. vallecaucensis Thatcher, 1970, parasites of dolphins and marsupials, respectively. The new species is similar in size and body form to A. vallecaucensis from which it differs in having a vitellarium that extends to the acetabulum while that of the former species are limited to the posterior one-third of the body. Additionally, the new species is from a rodent.

  1. Amphimerus bragai n. sp. (Digenea: Opisthorchiidae), a parasite of the rodent Nectomys squamipes (Cricetidae) from Minas Gerais, Brazil.

    Science.gov (United States)

    de Moraes Neto, A H; Thatcher, V E; Lanfredi, R M

    1998-01-01

    Amphimerus bragai n.sp. (Digenea, Opisthorchiidae) from the bile ducts of a rodent from the State of Minas Gerais, Brazil, Nectomys squamipes (Cricetidae), is described. The new species as studied by both light and scanning electron microscopy. A table is presented comparing the measurements of the new species with those of A. lancea (Diesing, 1850) and A. vallecaucensis Thatcher; 1970, parasites of dolphins and marsupials, respectively. The new species is similar in size and body form to A. vallecaucensis from which it differs in having a vitellarium that extends to the acetabulum while that of the former species are limited to the posterior one-third of the body. Additionally, the new species is from a rodent.

  2. On the occurrence of Holochilus chacarius (Cricetidae: Sigmodontinae in Brazil, with taxonomic notes on Holochilus species

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    Marcus Vinícius Brandão

    2015-03-01

    Full Text Available Currently four species of Holochilus (Cricetidae: Sigmodontinae are recognized. According to the literature, three species are recorded for Brazil: H. sciureus, H. brasiliensis and H. chacarius. Samples from western Brazil (Mato Grosso and Mato Grosso do Sul states are usually reported as H. sciureus and, when referring to specimens from the Pantanal, as H. chacarius. However, the taxonomic status of specimens from this region has not been properly evaluated through detailed morphological analyses or voucher specimens. About 110 specimens of Holochilus deposited in Brazilian collections were qualitatively and quantitatively analyzed (univariate and multivariate tests. Our results suggested the existence of three species (H. sciureus, H. brasiliensis and H. chacarius in Brazil, which present significant morphological and morphometric differences, thus confirming that the Mato Grosso and Mato Grosso do Sul samples, formerly misidentified as H. sciureus, belong to H. chacarius. This species differs from H. sciureus and H. brasiliensis by a series of pelage and skull characters, such as: the coloration of pelage, light orange-brown in the dorsum, light orangish in the flanks and white in the venter; ridges of the masseteric crest confluent at the level (or slightly above of the mental foramen and at the anterior part of m1, alternated main molar cusps, lophids compressed and with acute outer margins (rarely prismatic, anteromedian fossetid labially displaced and subcircular (small to medium, metaflexid less developed (frequently not reaching the midline of the tooth, proto and hipoconid subrectangular in outline and transversely orientated, mesoflexid transversely orientated and mesoloph absent. The updated geographic distribution of Holochilus in Brazil shows that H. sciureus is present in the northern portion of the country, being the only species present at the Amazon and at the Caatinga and with limit in the Cerrado biome at the center of Goi

  3. Ontogenetic and sexual variation in cranial characters of Aegialomys Xanthaeolus (Thomas, 1894(Cricetidae: Sigmodontinae from Ecuador and Peru

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    Joyce R. Prado

    2011-01-01

    Full Text Available Aegialomys xanthaeolus (Cricetidae: Sigmodontinae inhabits the arid montane areas of western Ecuador and Peru, and higher elevations in the upper Marañón valley in northern Peru. Some researchers have included this species in broader systematic assessments over the years, but there are no comprehensive studies focusing on intraspecific variation. There are several sources of intraspecific phenotypic variation, including sexual dimorphism and age. These sources may confound the assessment of similarity/dissimilarity among populations, therefore it is essential that non-geographic variation is evaluated before studies on geographical variation and species delimitation are carried out. Here we summarize existing information regarding the geographical distribution of A. xanthaeolus and evaluate variation related to sex and age. We analyzed 19 traditional cranio-dental measurements taken from specimens housed in scientific collections, and organized the collecting localities of specimens examined in a gazetteer and plotted them on a distribution map. Uni and multivariate statistical analyses allow us to assert that age variation was significant, as age classes 3, 4 and 5 can be pooled for the subsequent analysis of geographic variation and that sexual dimorphism is not a consistent component of variation within this species in the continental samples, when considering samples from the same locality, or localities close to each other.

  4. A Transitional Gundi (Rodentia: Ctenodactylidae from the Miocene of Israel.

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    Raquel López-Antoñanzas

    Full Text Available We describe a new species of gundi (Rodentia: Ctenodactylidae: Ctenodactylinae, Sayimys negevensis, on the basis of cheek teeth from the Early Miocene of the Rotem Basin, southern Israel. The Rotem ctenodactylid differs from all known ctenodactylid species, including Sayimys intermedius, which was first described from the Middle Miocene of Saudi Arabia. Instead, it most resembles Sayimys baskini from the Early Miocene of Pakistan in characters of the m1-2 (e.g., the mesoflexid shorter than the metaflexid, the obliquely orientated hypolophid, and the presence of a strong posterolabial ledge and the upper molars (e.g., the paraflexus that is longer than the metaflexus. However, morphological (e.g., presence of a well-developed paraflexus on unworn upper molars and dimensional (regarding, in particular, the DP4 and M1 or M2 differences between the Rotem gundi and Sayimys baskini distinguish them and testify to the novelty and endemicity of the former. In its dental morphology, Sayimys negevensis sp. nov. shows a combination of both the ultimate apparition of key-characters and incipient features that would be maintained and strengthened in latter ctenodactylines. Thus, it is a pivotal species that bridges the gap between an array of primitive ctenodactylines and the most derived, Early Miocene and later, gundis.

  5. Description of Litomosoides ysoguazu n. sp. (Nematoda, Onchocercidae), a parasite of the tuft-toed rice rat Sooretamys angouya (Fischer) (Rodentia: Cricetidae), and a first record of L. esslingeri Bain, Petit & Berteaux, 1989 in Paraguay.

    Science.gov (United States)

    Notarnicola, Juliana; de la Sancha, Noé Ulises

    2015-06-01

    Paraguay is a small landlocked country whose mammalian fauna is among the least studied in South America, as well as their parasites. As a result of a study of the effects of habitat fragmentation on small mammal biodiversity in eastern Paraguay, we have collected some parasites of cricetid rodents. Herein, we describe a new species of Litomosoides Chandler, 1931 parasitising the body cavity of the tuft-toed rice rat Sooretamys angouya (Fischer) and Litomosoides esslingeri Bain, Petit & Diagne, 1989 parasitising Oligoryzomys nigripes (Olfers), thus expanding its geographical distribution into Paraguay. Litomosoides ysoguazu n. sp. is characterised by the large size of the females (92.2-117.6 mm long) and by having buccal capsule with an anterior widening with rounded edges on the chitinous segment and a rounded widening at the base; male tail with a single pair of adcloacal papillae, three to five pairs of asymmetrical postcloacal papillae, and one or two unpaired papillae in the median ventral line; spicules corresponding to the "sigmodontis" species group; and microfilaria with a sheath stuck to the body and visible in the anterior extremity. We also describe a fourth-stage female larva. Oligoryzomys nigripes is a new host record of L. esslingeri; this enlarges the host record to eight species highlighting the low specificity of this species.

  6. First genotoxicity study of Paraná river water from Argentina using cells from the clam Corbicula fluminea (Veneroida Corbiculidae and Chinese hamster (Cricetulus griseus Rodentia, Cricetidae K1 cells in the comet assay

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    Jacqueline D. Caffetti

    2008-01-01

    Full Text Available High concentrations of xenobiotics from urban and industrial wastes have contributed to the contamination of many aquatic environments. We used the comet assay to evaluate the genotoxic potential of water collected from the River Paraná, which receives a great deal of waste, at three points (Puerto Piray, Eldorado and Montecarlo in the Misiones Province of Argentina. The in vivo comet assay used 40 freshwater clams (Corbicula fluminea while the in vitro comet assay used Chinese hamster (Cricetulus griseus K1 cell (CHO-K1 cultures with the mutagen ethyl methanesulfonate (EMS as the positive control and phosphate buffered saline (PBS as the negative control. Both assays showed statistically significant differences between the three sampling sites in relation to the negative control, the results of this preliminary study indicating that at these three sites water from the Paraná River presents genotoxic potential.

  7. MAMÍFEROS PEQUEÑOS EN LA DIETA DE LA LECHUZA TYTO ALBA (STRIGIFORMES: TYTONIDAE EN DOS LOCALIDADES DEL OCCIDENTE DE ECUADOR, CON AMPLIACIÓN DISTRIBUCIONAL DE ICHTHYOMYS HYDROBATES (RODENTIA: CRICETIDAE

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    JORGE BRITO M.

    2015-01-01

    Full Text Available En el presente estudio a partir de 107 egagrópilas de la lechuza, determinamos el consumo de 300 presas agrupadas en 21 especies, las egagrópilas fueron colectadas en dos localidades de diferente ambiente Los Santiagos y La Ciénaga, en las provincias de Chimborazo y Manabí, al occidente de Ecuador. Nuestros análisis revelaron una dieta compuesta mayoritariamente de mamíferos pequeños, sobre todo roedores, quienes constituyeron el 80%. Entre las presas más abundantes se encontró a Oligoryzomys sp. que representó el 38.7% de la dieta en las muestras de Los Santiagos y Sigmodon peruanus 33.6% en La Ciénaga, siendo el 22,5% y 41% respectivamente de la biomasa total consumida para cada sitio. La rata cangrejera Ichthyomys hydrobates es reportada por primera vez en la dieta de la lechuza y también en la localidad de Los Santiagos, ampliando el rango distribucional de este roedor para el centro-sur al occidente de Ecuador en aproximadamente 200 km.

  8. Karyotypes of two rare rodents, Hapalomys delacouri and Typhlomys cinereus (Mammalia, Rodentia), from Vietnam.

    Science.gov (United States)

    Abramov, Alexei V; Aniskin, Vladimir M; Rozhnov, Viatcheslav V

    2012-01-01

    Karyotypes of Hapalomys delacouri (Rodentia, Muridae) and Typhlomys cinereus (Rodentia, Platacanthomyidae) from Vietnam are described for the first time. The diploid karyotype of Hapalomys delacouri is 38 (NFa=48), consisting of six pairs of bi-armed and 12 pairs of acrocentric autosomes decreasing in size; plus a large metacentric X chromosome and Y chromosome, also metacentric, that is equal in size to the largest pair of acrocentric autosomes. The newly described karyotype differs significantly from that reported for Hapalomys delacouri from northern Thailand. The latter record very likely represents a different species of Hapalomys, possibly the taxon Hapalomys pasquieri described from north-central Laos.The diploid karyotype of Typhlomys cinereus is 38 (NF=48), consisting of five pairs of meta- to submetacentric and 14 pairs of acrocentric chromosomes varying in size from large to small; sex chromosomes were not defined.

  9. Karyotypes of two rare rodents, Hapalomys delacouri and Typhlomys cinereus (Mammalia, Rodentia, from Vietnam

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    Alexei Abramov

    2012-01-01

    Full Text Available Karyotypes of Hapalomys delacouri (Rodentia, Muridae and Typhlomys cinereus (Rodentia, Platacanthomyidae from Vietnam are described for the first time. The diploid karyotype of H. delacouri is 38 (NFa=48, consisting of six pairs of bi-armed and 12 pairs of acrocentric autosomes decreasing in size; plus a large metacentric X chromosome and Y chromosome, also metacentric, that is equal in size to the largest pair of acrocentric autosomes. The newly described karyotype differs significantly from that reported for H. delacouri from northern Thailand. The latter record very likely represents a different species of Hapalomys, possibly the taxon H. pasquieri described from north-central Laos. The diploid karyotype of Typhlomys cinereus is 38 (NF=48, consisting of five pairs of meta- to submetacentric and 14 pairs of acrocentric chromosomes varying in size from large to small; sex chromosomes were not defined.

  10. On subspecific taxonomy of Microtus savii (Rodentia, Arvicolidae

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    Longino Contoli

    2003-10-01

    Full Text Available Riassunto Sulla tassonomia sottospecifica di Microtus savii (Rodentia, Arvicolidae Viene riveduta e riassunta la situazione tassonomica sottospecifica di Microtus (Terricola savii, anche tramite la descrizione di due nuovi taxa: Microtus (Terricola savii tolfetanus, dei Monti della Tolfa e Microtus (Terricola savii niethammericus, del Gargano.

  11. The role of growth stop as a morphogenetic factor in Mastomys natalensis (Rodentia: Muridae)

    DEFF Research Database (Denmark)

    Fadda, Carlo; Leirs, Herwig

    2009-01-01

    The present study investigated growth patterns under three different environmental conditions in a single population of the rodent Mastomys natalensis (Rodentia, Muridae) in Morogoro, Tanzania. The study aimed to test whether and how post-weaning ontogenetic processes are affected by different en...

  12. Identification of lymphocytic choriomeningitis mammarenavirus in house mouse (Mus musculus, Rodentia) in French Guiana.

    Science.gov (United States)

    Lavergne, Anne; de Thoisy, Benoît; Tirera, Sourakhata; Donato, Damien; Bouchier, Christiane; Catzeflis, François; Lacoste, Vincent

    2016-01-01

    Thirty-seven house mice (Mus musculus, Rodentia) caught in different localities in French Guiana were screened to investigate the presence of lymphocytic choriomeningitis mammarenavirus (LCMV). Two animals trapped in an urban area were found positive, hosting a new strain of LCMV, that we tentatively named LCMV "Comou". The complete sequence was determined using a metagenomic approach. Phylogenetic analyses revealed that this strain is related to genetic lineage I composed of strains inducing severe disease in humans. These results emphasize the need for active surveillance in humans as well as in house mouse populations, which is a rather common rodent in French Guianese cities and settlements.

  13. Projecto Rodentia : etologia aplicada na sala de aula do 1º Ciclo

    OpenAIRE

    2008-01-01

    p. 275-279 O Projecto Rodentia, implementado no ano 2006/2007, visa promover a cultura científica em alunos do 1º ciclo do Ensino Básico, familiarizando-os com o Método Científico e desenvolvendo competências conceptuais, processuais e atitudinais, com base na Etologia Aplicada e na reflexão ética sobre o bem-estar animal. Foram instalados em três salas de aula habitats especialmente desenhados, contendo cada um dois ratos de laboratório. Inicialmente orien...

  14. The helminth community of Apodemus sylvaticus (Rodentia, Muridae in the Sierra de Gredos (Spain

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    Fuentes, M. V.

    2005-02-01

    Full Text Available The Spanish mountain range of Gredos was included in the studies conducted on the Iberian peninsula to investigate helminth fauna of small mammals. The helminth community of the wood mouse, Apodemus sylvaticus (Rodentia, Muridae, was analysed. Qualitatively, 13 helminth species were detected: Plagiorchis sp. I and Plagiorchis sp. II (Trematoda; Taenia parva larvae, T. martis larvae, T. taeniaeformis larvae, Rodentolepis straminea and R. fraterna (Cestoda; and Trichuris muris, Heligmosomoides polygyrus, Syphacia stroma, S. frederici, Aspiculuris tetraptera and Rictularia proni (Nematoda. Quantitatively, the highest prevalence (65.0% and the mean abundance (36.9% of H. polygyrus stand out. In comparison with the other mountain ranges studied, analysis of the global results demonstrates that the helminth fauna of the host species studied is diverse despite the adverse climatic conditions. This could be related to both the particular ecological characteristics and the appropriate state of preservation of this ecosystem.

  15. A new species, Litomosoides odilae n. sp (Nematoda: Onchocercidae) from Oligoryzomys nigripes (Rodentia: Muridae) in the rainforest of Misiones, Argentina.

    Science.gov (United States)

    Notarnicola, Juliana; Navone, Graciela

    2002-10-01

    A new species of Litomosoides was collected from the abdominal cavity of Oligoryzomys nigripes (Rodentia: Muridae) in a semideciduous secondary rainforest of Misiones, Argentina. Litomosoides odilae n. sp. belongs to the carinii group and is characterized by the amphids displaced dorsally; buccal capsule with an anterior segment transparent and an annular asymmetrical thickening; esophagus divided, with the posterior glandular portion slightly wider than the muscular; male cloacal aperture strongly protruded; and microfilaria sheathed with an attenuated tail. The morphology of the new species, which is similar to that of L petteri, a parasite of marsupials in Brazil, suggests that host-switching events may have occurred in the diversification of this genus.

  16. A new genus and species of Heligmonellidae (Nematoda: Trichostrongylina) parasitic in Delomys dorsalis (Rodentia: Sigmodontinae) from Misiones, Argentina.

    Science.gov (United States)

    Digiani, María Celina; Kinsella, John M

    2014-10-01

    Alippistrongylus bicaudatus gen. et sp. n. (Nematoda: Heligmonellidae) is described from the striped Atlantic forest rat, Delomys dorsalis (Hensel) (Rodentia: Sigmodontinae), from the province of Misiones in Argentina. The new genus and species is characterised by a synlophe of 21 unequal ridges in both sexes without a gradient in size, with two ridges weakly sclerotised and oriented perpendicularly in the dorsal left quadrant; males with a highly dissymmetrical bursa with a hypertrophied right lobe, and females with a dorsal conical appendage just posterior to the vulva, conferring a two-tailed appearance to the female worms.

  17. Two new species of Litomosoides (Nemata:Onchocercidae) from Ctenomys opimus (Rodentia:Ctenomyidae) on the altiplano of Bolivia.

    Science.gov (United States)

    Brant, S V; Gardner, S L

    1997-08-01

    Two filarioid nematodes, Litomosoides andersoni n. sp. and Litomosoides ctenomyos n. sp. (Nemata: Onchocercidae), are described from the mesenteries of the subterranean rodent Ctenomys opimus (Rodentia: Hystrichognathi) collected on the altiplano of Bolivia. Specimens collected near Rancho Huancaroma (Oruro Dept.) in 1984 and 1986 can be recognized as undescribed by the structures of the spicules and stoma and the shape of the ovijector. This record represents the first time members of the genus Litomosoides have been recovered from rodents of the family Ctenomyidae; this also represents the first published report of these nematodes from mammals in Bolivia.

  18. Description of the karyotype of Rhagomys rufescens Thomas, 1886 (Rodentia, Sigmodontinae from Southern Brazil Atlantic forest

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    André Filipe Testoni

    2010-01-01

    Full Text Available Rhagomys rufescens (Rodentia: Sigmodontinae is an endemic species of the Atlantic forest from Southern and Southeastern Brazil. Some authors consider Rhagomys as part of the tribe Thomasomyini; but its phylogenetic relationships remain unclear. Chromosomal studies on eight specimens of Rhagomys rufescens revealed a diploid number of 2n = 36 and a number of autosome arms FN = 50. GTG, CBG and Ag-NOR banding and CMA3/DAPI staining were performed on metaphase chromosomes. Eight biarmed and nine acrocentric pairs were found in the karyotype of this species. The X and Y chromosomes were both acrocentric. Most of the autosomes and the sex chromosomes showed positive C-bands in the pericentromeric region. The X chromosome showed an additional heterochromatic block in the proximal region of the long arm. Nucleolus organizer regions (NORs were located in the pericentromeric region of three biarmed autosomes (pairs 4, 6 and 8 and in the telomeric region of the short arm of three acrocentrics (pairs 10, 12 and 17. CMA3/DAPI staining produced fluorescent signals in many autosomes, especially in pairs 4, 6, and 8. This study presents cytogenetic data of Rhagomys rufescens for the first time.

  19. Historical Review and Notes on Small Mammals (Mammalia: Erinaceomorpha, Soricomorpha, Rodentia in Korea

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    Lee, Jeong-Boon

    2014-07-01

    Full Text Available A taxonomic study of small mammals (Erinaceomorpha, Soricomorpha and Rodentia was conducted in order to find out the scientific names which have been used in Korea. The synonymy of each species and taxonomical research was reviewed and confirmed in this study. The species names are rearranged based on recent studies. Among the various confused names, available names were adopted such as follows: C. shantungensis shantungensis known as Crocidura suaveolens; C. shantungensis quelpartis known as C. dsinezumi; Rattus tanezumi known as R. rattus, called black rat, roof rat and ship rat, respectively. Apodemus sylvaticus (Muridae, wood mouse is excluded in the checklist based on indistinct previous records and ambiguous habitation on the Korean Peninsula, and neighbors. In addition, we provide a new Korean vernacular name for Myocastor coypus, called the "Nutria" in Korea. We reflect that several species are repositioned to other genera. A checklist of Korean small mammals and synonym list for each species is provided to avoid confusion of scientific names in Korea. In this study, the list of small mammals in Korea is arranged to 33 species, 20 genera, 8 families, and 3 orders.

  20. The complete mitochondrial genome of Microtus fortis calamorum (Arvicolinae, Rodentia) and its phylogenetic analysis.

    Science.gov (United States)

    Jiang, Xianhuan; Gao, Jun; Ni, Liju; Hu, Jianhua; Li, Kai; Sun, Fengping; Xie, Jianyun; Bo, Xiong; Gao, Chen; Xiao, Junhua; Zhou, Yuxun

    2012-05-01

    Microtus fortis is a special resource of rodent in China. It is a promising experimental animal model for the study on the mechanism of Schistosome japonicum resistance. The first complete mitochondrial genome sequence for Microtus fortis calamorum, a subspecies of M. fortis (Arvicolinae, Rodentia), was reported in this study. The mitochondrial genome sequence of M. f. calamorum (Genbank: JF261175) showed a typical vertebrate pattern with 13 protein coding genes, 2 ribosomal RNAs, 22 transfer RNAs and one major noncoding region (CR region).The extended termination associated sequences (ETAS-1 and ETAS-2) and conserved sequence block 1 (CSB-1) were found in the CR region. The putative origin of replication for the light strand (O(L)) of M. f. calamorum was 35bp long and showed high conservation in stem and adjacent sequences, but the difference existed in the loop region among three species of genus Microtus. In order to investigate the phylogenetic position of M. f. calamorum, the phylogenetic trees (Maximum likelihood and Bayesian methods) were constructed based on 12 protein-coding genes (except for ND6 gene) on H strand from 16 rodent species. M. f. calamorum was classified into genus Microtus, Arvcicolinae for the highly phylogenetic relationship with Microtus kikuchii (Taiwan vole). Further phylogenetic analysis results based on the cytochrome b gene ranged from M. f. calamorum to one of the subspecies of M. fortis, which formed a sister group of Microtus middendorfii in the genus Microtus.

  1. Codivergence in heteromyid rodents (Rodentia: heteromyidae) and their sucking lice of the genus Fahrenholzia (Phthiraptera: anoplura).

    Science.gov (United States)

    Light, Jessica E; Hafner, Mark S

    2008-06-01

    Although most studies of codivergence rely primarily on topological comparisons of host and parasite phylogenies, temporal assessments are necessary to determine if divergence events in host and parasite trees occurred contemporaneously. A combination of cophylogenetic analyses and comparisons of branch lengths are used in this study to understand the host-parasite association between heteromyid rodents (Rodentia: Heteromyidae) and their sucking lice of the genus Fahrenholzia (Phthiraptera: Anoplura). Cophylogenetic comparisons based on nucleotide substitutions in the mitochondrial COI gene reveal a significant, but not perfect, pattern of cophylogeny between heteromyids and their sucking lice. Regression analyses show a significant functional relationship between the lengths of analogous branches in the host and parasite trees, indicating that divergence events in hosts and parasites were approximately contemporaneous. Thus, the topological similarity observed between heteromyids and their lice is the result of codivergence. These analyses also show that the COI gene in lice is evolving two to three times faster than the same gene in their hosts (similar to the results of studies of other lice and their vertebrate hosts) and that divergence events in lice occurred shortly after host divergence. We recommend that future studies of codivergence include temporal comparisons and, when possible, use the same molecular marker(s) in hosts and parasites to achieve the greatest insight into the history of the host-parasite relationship.

  2. Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae).

    Science.gov (United States)

    Luis, Juana; Ramírez, Lorena; Carmona, Agustín; Ortiz, Guadalupe; Delgado, Jesús; Cárdenas, René

    2009-01-01

    Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of paternal care. In captivity, males of Volcano Mouse (Neotomodon alstoni) provide pups the same care provided by the mother, with the exception of suckling. Here we measured plasmatic testosterone concentrations 10 days after mating, five and 20 days postpartum, and 10 days after males were isolated from their families in order to determine possible changes in this hormone, associated to the presence and age of pups. Males of Volcano Mouse exhibited paternal behavior when their testosterone levels were relatively high. Although levels of this hormone did not change with the presence or pups age, males that invested more time in huddling showed higher testosterone levels. It is possible that in the Volcano Mouse testosterone modulates paternal behavior indirectly, as in the California mouse.

  3. Helminth fauna of the Siberian chipmunk, Tamias sibiricus Laxmann (Rodentia, Sciuridae) introduced in suburban French forests.

    Science.gov (United States)

    Pisanu, Benoît; Jerusalem, Christelle; Huchery, Cindy; Marmet, Julie; Chapuis, Jean-Louis

    2007-05-01

    The spread of an immigrant host species can be influenced both by its specific helminth parasites that come along with it and by newly acquired infections from native fauna. The Siberian chipmunk, Tamias sibiricus Laxmann (Rodentia, Sciuridae), a northeastern Eurasiatic ground nesting Sciurid, has been introduced in France for less than three decades. Thirty individuals were collected from three suburban forests in the Ile-de-France Region between 2002 and 2006. Two intestinal nematode species dominated the helminth fauna: Brevistriata skrjabini [Prevalence, P, 99% C.I., 87% (64-97%); mean intensity, M.I., 99% C.I., 43 (28-78)] and Aonchotheca annulosa [P, 47% (25-69%); M.I., 35 (3-157)]. B. skrjabini is a direct life cycle nematode species of North Eurasiatic origin, with a restricted spectrum of phylogenetically related suitable hosts. This result indicates that B. skrjabini successfully settled and spread with founder pet chipmunks maintained in captivity and released in natura. Chipmunks acquired A. annulosa, a nematode species with a large spectrum of phylogenetically unrelated suitable host species, from local Muroid rodent species with similar behavior, life-history traits and habitats. Quantitative studies are needed to evaluate the potential for both B. skrjabini and A. annulosa to impede the spread of Tamias and for B. skrjabini to favor chipmunk colonization through detrimental effects upon native co-inhabiting host species.

  4. Extended longevity of reproductives appears to be common in Fukomys mole-rats (Rodentia, Bathyergidae.

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    Philip Dammann

    Full Text Available African mole-rats (Bathyergidae, Rodentia contain several social, cooperatively breeding species with low extrinsic mortality and unusually high longevity. All social bathyergids live in multigenerational families where reproduction is skewed towards a few breeding individuals. Most of their offspring remain as reproductively inactive "helpers" in their natal families, often for several years. This "reproductive subdivision" of mole-rat societies might be of interest for ageing research, as in at least one social bathyergid (Ansell's mole-rats Fukomys anselli, breeders have been shown to age significantly slower than non-breeders. These animals thus provide excellent conditions for studying the epigenetics of senescence by comparing divergent longevities within the same genotypes without the inescapable short-comings of inter-species comparisons. It has been claimed that many if not all social mole-rat species may have evolved similar ageing patterns, too. However, this remains unclear on account of the scarcity of reliable datasets on the subject. We therefore analyzed a 20-year breeding record of Giant mole-rats Fukomys mechowii, another social bathyergid species. We found that breeders indeed lived significantly longer than helpers (ca. 1.5-2.2fold depending on the sex, irrespective of social rank or other potentially confounding factors. Considering the phylogenetic positions of F. mechowii and F. anselli and unpublished data on a third Fukomys-species (F. damarensis showing essentially the same pattern, it seems probable that the reversal of the classic trade-off between somatic maintenance and sexual reproduction is characteristic of the whole genus and hence of the vast majority of social mole-rats.

  5. Postnatal ontogeny of limb proportions and functional indices in the subterranean rodent Ctenomys talarum (Rodentia: Ctenomyidae).

    Science.gov (United States)

    Echeverría, Alejandra Isabel; Becerra, Federico; Vassallo, Aldo Iván

    2014-08-01

    Burrow construction in the subterranean Ctenomys talarum (Rodentia: Ctenomyidae) primarily occurs by scratch-digging. In this study, we compared the limbs of an ontogenetic series of C. talarum to identify variation in bony elements related to fossorial habits using a morphometrical and biomechanical approach. Diameters and functional lengths of long bones were measured and 10 functional indices were constructed. We found that limb proportions of C. talarum undergo significant changes throughout postnatal ontogeny, and no significant differences between sexes were observed. Five of six forelimb indices and two of four hindlimb indices showed differences between ages. According to discriminant analysis, the indices that contributed most to discrimination among age groups were robustness of the humerus and ulna, relative epicondylar width, crural and brachial indices, and index of fossorial ability (IFA). Particularly, pups could be differentiated from juveniles and adults by more robust humeri and ulnae, wider epicondyles, longer middle limb elements, and a proportionally shorter olecranon. Greater robustness indicated a possible compensation for lower bone stiffness while wider epicondyles may be associated to improved effective forces in those muscles that originate onto them, compensating the lower muscular development. The gradual increase in the IFA suggested a gradual enhancement in the scratch-digging performance due to an improvement in the mechanical advantage of forearm extensors. Middle limb indices were higher in pups than in juveniles-adults, reflecting relatively more gracile limbs in their middle segments, which is in accordance with their incipient fossorial ability. In sum, our results show that in C. talarum some scratch-digging adaptations are already present during early postnatal ontogeny, which suggests that they are prenatally shaped, and other traits develop progressively. The role of early digging behavior as a factor influencing on

  6. Squamasnema amazonica n. gen. n. sp. (Heligmonellinae): A new parasite of Proechimys roberti (Rodentia: Echimyidae) in the Brazilian Amazon.

    Science.gov (United States)

    Cordeiro, Helrik da Costa; Melo, Francisco Tiago de Vasconcelos; Furtado, Adriano Penha; Giese, Elane Guerreiro; Maldonado, Arnaldo; dos Santos, Jeannie Nascimento

    2015-08-01

    A new species of nematode, Squamasnema amazonica n. gen. n. sp., is described based on specimens found parasitizing the small intestine of Proechimys roberti (Rodentia: Echimyidae) collected during a survey of the fauna of Tapirapé-Aquirí National Forest (Brazil, Eastern Brazilian Amazon). The nematodes were fixed and processed for light microscopy and scanning electron microscopy (SEM). These nematodes were classified under the family Heligmonellidae and the subfamily Heligmonellinae. Although several species in the family Heligmonellidae exhibit discontinuous ridges, Squamasnema n. gen. and Trichotravassosia are the only genera with columns of scales along their entire body, as an apomorphy of the synlophe. Squamasnema n. gen. has columns of cuticular cells along its body, except for on the left flank, and exhibits a synlophe with no size gradient or inclination and does not present chitinized structures supporting the synlophe. Therefore, due to these morphological differences of Squamasnema n. gen., the creation of a new genus was necessary.

  7. Redescription of Trichuris pampeana (Nematoda: Trichuridae) from the South American subterranean rodent Ctenomys talarum Thomas, 1898 (Rodentia: Octodontidae).

    Science.gov (United States)

    Rossin, M Alejandra; Malizia, Ana I

    2005-02-01

    Trichuris pampeana Suriano and Navone, 1994 (Nematoda: Trichuridae) is redescribed from voucher specimens from the type host Ctenomys azarae Thomas, 1903 (Rodentia: Octodontidae) and from parasites collected from 2 populations of the subterranean rodent C. talarum Thomas, 1898 from Mar de Cobo and Necochea, Buenos Aires Province, Argentina. After a revision of these nematodes, it was confirmed that the following characters were not considered in the original description: bacillary band, cells from the esophagointestinal junction, ejaculatory duct, vas deferens, adanal papillae, vagina, oviduct, and rectum. Additional information about the spicular sheath, vulva, uteri, and ovary is provided. The morphological features given in this redescription allow to confirm the identity of T. pampeana as a valid species and also to distinguish it more clearly from other species of the genus.

  8. A classification of the Gliridae (Rodentia on the basis of dental morphology

    Directory of Open Access Journals (Sweden)

    Remmert Daams

    1995-05-01

    Full Text Available Abstract The supra-familiar relationships of the Gliridae are discussed. The criterion used for subdividing the Gliridae is the morphology of the cheek teeth because this is the only character known for all taxa. This limitation leads to the undesirable "synonymy" of Glamys and Gliravus, two genera whose type species have a very different skull morphology, and to the incorporation into the Dryomyinae of Graphiurus and Leithia, despite the fact that Dryomys has a myomorph, Graphiurus a hystricomorph and Leithia a sciuromorph skull. The hundred and seventy-seven species and thirty eight genera of dormice are grouped into five subfamilies. One of these, the Bransatoglirinae, is new. The subfamily Graphiurinae is supressed and Graphiurus is assigned to the Dryomyinae. The genera of the Gliridae and the species allocated to them are listed in the appendix in alphabetical order. The original diagnoses of the genera are given in English and the type locality, type level and synonymy of each species is given. Riassunto Una classificazione di Gliridae (Rodentia sulla base della morfologia dentale - Vengono discusse le relazioni soprafamiliari dei Gliridi. I1 criterio utilizzato per la suddivisione dei Gliridi è la morfologia dei denti molari poiché è l'unico carattere noto per tutti i taxa. Questa limitazione porta alla "sinonimia" non voluta di Glamys e Gliravus, due generi le cui specie tipiche presentano una struttura del cranio molto diversa, ed alla incorporazione di Graphiurus e Leithia nei Dryomyinae, sebbene Dryomys abbia un cranio miomorfo, Graphiurus un cranio istricomorfo e Leithia un cranio sciuromorfo. Le centosettantasette specie ed i trentotto generi di Gliridi sono raggruppati in cinque sottofamiglie. Una di queste, Bransatoglirinae, è nuova. La

  9. A phylogeographic study of the endemic rodent Eliurus carletoni (Rodentia: Nesomyinae) in an ecological transition zone of Northern Madagascar.

    Science.gov (United States)

    Rakotoarisoa, Jean-Eric; Raheriarisena, Martin; Goodman, Steven M

    2013-01-01

    We conducted a mitochondrial phylogeographic study of the endemic dry forest rodent Eliurus carletoni (Rodentia: Nesomyinae) in an ecological transition zone of northern Madagascar (Loky-Manambato) and 2 surrounding regions (Ankarana and Analamerana). The main goal was to assess the evolutionary consequences on this taxon of the complex landscape features and Quaternary ecological vicissitudes. Three haplogroups were identified from the 215 specimens obtained from 15 populations. High levels of genetic diversity and significant genetic differentiation among populations were observed. The different geographical subdivisions of the study area by regions, by river catchment zones, and the physical distance between populations are not correlated with genetic patterns. In contrast, population structure is mostly explained by the geographic distribution of the samples among existing forest blocks. E. carletoni experienced a genetic bottleneck between 18 750 and 7500 years BP, which correlates with periods when moister climates existed on the island. Overall, our data suggest that the complex genetic patterns of E. carletoni can be explained by Quaternary climatic vicissitudes that resulted in habitat fluctuations between dry and humid forests, as well as subsequent human-induced fragmentation of forest habitat.

  10. Trypanosoma (Megatrypanum) lainsoni n. sp. from Mesomys hispidus (Rodentia: Echimyidae) in Brazil: trypomastigotes described from experimentally infected laboratory mice.

    Science.gov (United States)

    Naiff, Roberto Daibes; Barrett, Toby Vincent

    2013-01-01

    We report the detection, isolation and description of Trypanosoma (Megatrypanum) lainsoni n. sp. from a caviomorph rodent, Mesomys hispidus (Rodentia: Echimyidae), obtained in the Rio Negro region of the state of Amazonas, in northern Brazil. Laboratory-bred white mice (Mus musculus) and rats (Rattus rattus) were inoculated with large numbers of culture forms by intraperitoneal route, and trypomastigotes appeared in their blood 3-8 days post-inoculation. One single epimastigote was also found in Mus musculus. Similar attempts to infect Rattus norvegicus, hamsters (Mesocricetus auratus), the opossum Didelphis marsupialis, the anteater Tamandua tetradactyla and triatomine bugs were unsuccessful, following six months of observations and microscopic examinations of blood films and blood cultures. As we have found no previous record of a Trypanosoma (Megatrypanum) species naturally infecting a member of the family Echimyidae, or any other caviomorph rodent, we conclude that this is the first time such an infection has been reported. The new species is unusual in the subgenus for its infectivity to laboratory mice.

  11. Catalog of type specimens of recent mammals: Rodentia (Sciuromorpha and Castorimorpha) in the National Museum of Natural History, Smithsonian Institution

    Science.gov (United States)

    Fisher, Robert D.; Ludwig, Craig A.

    2012-01-01

    The type collection of Recent mammals in the Division of Mammals, National Museum of Natural History, Smithsonian Institution, contains 843 specimens bearing names of 820 species group taxa of Rodentia (Sciuromorpha and Castorimorpha) as of July 2011. This catalog presents a list of these holdings, which comprise 798 holotypes, 14 lectotypes, seven syntypes (30 specimens), and one neotype. In addition, we include three holotypes and 10 specimens that are part of syntype series that should be in the collection but cannot be found and three syntypes that were originally in this collection but are now known to be in other collections. One specimen that no longer has name-bearing status is included for the record. Forty-one of the names are new since the last type catalog. One new lectotype is designated. Suborders and families are listed as in Wilson and Reeder. Within families, currently recognized genera are arranged alphabetically. Within each currently recognized genus, accounts are arranged alphabetically by original published name. Information in each account includes original name and abbreviated citation thereto, current name if other than original, citation for first use of current name combination for the taxon (or new name combination if used herein for the first time), type designation, U.S. National Museum catalog number(s), preparation, age and sex, type locality, date of collection and name of collector, collector’s original number, and comments or additional information as appropriate. Digital photographs of each specimen serve as a condition report and will be linked to each electronic specimen record.

  12. The chromosome complement of Acomys spp. (Rodentia, Muridae) from Oursi, Burkina Faso--the ancestral karyotype of the cahirinus-dimidiatus group?

    Science.gov (United States)

    Volobouev, V; Gautun, J C; Sicard, B; Tranier, M

    1996-11-01

    We present here data on chromosome banding analysis (R- and C-bands) of Acomys sp. (Rodentia, Muridae) from Oursi, Burkina Faso, characterized by 2n = FN = 68 and comparison of its banding patterns with those of Acomys dimidiatus from Saudi Arabia (2n = 38, FN = 70), studied previously. The study revealed complete homology between acrocentric chromosomes of Acomys sp. and chromosome arms of 16 pairs of metacentric and two pairs of acrocentric chromosomes of A. dimidiatus. In addition to monobrachial homology, one tandem translocation accompanied by a centromeric shift was identified in the karyotype of the latter species. The data obtained show that karyotypes of all the species of the Acomys cahirinus-dimidiatus group studied previously may be derived from that of Acomys sp. from Oursl by means of numerous non-homologous Rb translocations and 1-2 tandem transiocations, and thus its karyotype may be considered as ancestral for the cahirinus-dimidiatus group.

  13. The role of the subterranean rodent Ctenomys talarum (Rodentia: Octodontidae) in the life cycle of Taenia taeniaeformis (Cestoda: Taeniidae) in urban environments.

    Science.gov (United States)

    Rossin, Alejandra; Malizia, Ana I; Denegri, Guillermo M

    2004-06-10

    This work is the first report of subterranean rodent Ctenomys talarum (Rodentia: Octodontidae) as intermediate host of Taenia taeniaeformis in urban areas of Mar de Cobo (Buenos Aires Province, Argentina) and to experimentally reproduce in domestic dogs the adult stage of this parasite. Prevalence, mean abundance and mean intensity of infection with T. taeniaeformis larvae in the liver and peritoneal cavity of C. talarum were 64%, 15.3 and 9.8, respectively. Ten adults of T. taeniaeformis were obtained from experimentally infected dogs. Information about the role of subterranean rodents in the life cycle of this parasite is also given. The above mentioned data indicate that T. taeniaeformis is a frequent parasite of this species of rodents, at least within the study area. Also explanations for the high prevalence of larval forms of this parasite in C. talarum populations are given.

  14. Third lineage of rodent eimerians: morphology, phylogeny and re-description of Eimeria myoxi (Apicomplexa: Eimeriidae) from Eliomys quercinus (Rodentia: Gliridae).

    Science.gov (United States)

    Kvičerová, Jana; Mikeš, Václav; Hypša, Václav

    2011-09-01

    Coccidian oocysts from feces of 46 individuals of the garden dormouse, Eliomys quercinus (Rodentia: Gliridae), were morphologically and molecularly characterized. Both morphological and sequence data (18S rDNA and ORF 470) showed low variability, indicating that all samples represent a single species. By comparison with published morphological descriptions of coccidia from glirid rodents, we determined that the samples represent Eimeria myoxi. Molecular data suggest that this species does not fall within the 2 known rodent-specific groups but branches as a third independent lineage. However, its exact position in respect to other eimerian clusters could not be established due to the lack of phylogenetic information at this taxonomic level for the 18S rRNA and ORF 470 genes. Based on these results, we provide a re-description of Eimeria myoxi, which contains morphological and molecular characteristics sufficient for its further unequivocal identification.

  15. Suprafamilial relationships among Rodentia and the phylogenetic effect of removing fast-evolving nucleotides in mitochondrial, exon and intron fragments

    Directory of Open Access Journals (Sweden)

    Arnal Véronique

    2008-11-01

    Castorimorpha (Castoridae + Geomyoidea. The second suprafamilial clustering identified a novel association between the Sciuromorpha (Gliridae + (Sciuridae + Aplodontidae and the Hystricomorpha (Ctenodactylidae + Hystricognathi which together represents the earliest dichotomy among Rodentia. Molecular time estimates using a relaxed Bayesian molecular clock dates the appearance of the five suborders nearly contemporaniously at the KT boundary and this is congruent with suggestions of an early explosion of rodent diversity. Based on these newly proposed phylogenetic relationships, the evolution of the zygomasseteric pattern that has been used for a long time in rodent systematics is evaluated.

  16. Catalog of type specimens of recent mammals: orders Didelphimorpha through Chiroptera (Excluding Rodentia) in the National Museum of Natural History, Smithsonian Institution

    Science.gov (United States)

    Fisher, Robert D.; Ludwig, Craig A.

    2015-01-01

    The type collection of Recent Mammals in the Division of Mammals, National Museum of Natural History, Smithsonian Institution, contains 820 specimens bearing names of 809 species-group taxa of Didelphimorphia through Chiroptera, excluding Rodentia, as of June 2014. This catalog presents an annotated list of these holdings comprised of 788 holotypes, 26 lectotypes, 11 syntypes (22 specimens), and 4 neotypes. Included are several specimens that should be in the collection but cannot be found or are now known to be in other collections. One hundred and twenty-seven of the names are new since the last type catalog covering these orders, Poole and Schantz (1942). Five specimens reported in Poole and Schantz (1942) were subsequently sent to the Vertebrate Paleontology collection and are not included here. Orders and families are ordered as in Wilson and Reeder (2005); within families, currently recognized genera are arranged alphabetically; within each currently recognized genus, accounts are arranged alphabetically by original published name. Information in each account includes original name and abbreviated citation thereto, current name if other than original, citation for first use of current name combination for the taxon (or new name combination if used herein for the first time), type designation, U.S. National Museum catalog number(s), preparation, age and sex, date of collection and collector, original collector number, type locality, and remarks as appropriate. Digital photographs of each specimen will serve as a condition report and will be attached to each electronic specimen record.

  17. Catalog of type specimens of recent mammals: Rodentia (Myomorpha, Anomaluromorpha, and Hystricomorpha) in the National Museum of Natural History, Smithsonian Institution

    Science.gov (United States)

    Fisher, Robert D.; Ludwig, Craig A.

    2014-01-01

    The type collection of Recent mammals in the Division of Mammals, National Museum of Natural History, Smithsonian Institution, contains 945 specimens bearing names of 931 species-group taxa of Rodentia (Myomorpha, Anomaluromorpha, and Hystricomorpha) as of August 2013. This catalog presents an annotated list of these holdings comprised of 905 holotypes, 16 lectotypes, 8 syntypes (48 specimens), and 2 neotypes. In addition, we include 44 specimens that are part of syntype series that should be in the collection but cannot be found or are now known to be in other collections. One hundred and ten of the names are new since the last type catalog covering these suborders A lectotype for Mus peruvianus Peale, 1848, is newly designated herein. Nine specimens previously reported were subsequently sent to the vertebrate paleontology collection and are not included here. Suborders and families are ordered as in Carleton and Musser; within families, currently recognized genera are arranged alphabetically; within each currently recognized genus, accounts are arranged alphabetically by original published name. Information in each account includes original name and abbreviated citation thereto, current name if other than original, citation for first use of current name combination for the taxon (or new name combination if used herein for the first time), type designation, U.S. National Museum catalog number(s), preparation, age and sex, date of collection and collector, original collector number, type locality, and remarks as appropriate. Digital photographs of each specimen will serve as a condition report and will be attached to each electronic specimen record.

  18. Rodentia and lagomorpha

    Science.gov (United States)

    Sheffield, S.R.; Sawicka-Kapusta, K.; Cohen, J.B.; Rattner, B.A.; Shore, Richard F.; Rattner, Barnett A.

    2001-01-01

    This comprehensive review examines the extensive literature on wild rodents and lagomorphs as biomonitors of environmental contamination. This chapter covers studies dealing with exposure and effects of environmental contaminants on rodent and lagomorph species, including pesticides (organochlorines, organophosphorus and carbamate compounds, herbicides, plant growth regulators, fungicides, and rodenticides), other organic chemicals, metals, radionuclides, and other miscellaneous contaminants. Many research needs become evident when reviewing ecotoxicological data for rodents and lagomorphs, the most striking being the paucity of information on rodent families other than Muridae (mice and rats). While our ability to qualitatively extrapolate effects observed in laboratory studies to field situations is good for a variety of contaminants, quantitative predictions of dose-response relationships are poor because inter-specific variation and differences in exposure patterns between laboratory and wild species to toxicants are for the most part unknown. More sophisticated comparative toxicity studies need to be undertaken that build on previous work in order to develop a database of information, to account for and model differences in exposure pathways, to document interactions among multiple stressors, to generate data establishing thresholds, critical concentrations, and diagnostic guidelines, and even to develop physiologically-based toxicokinetic models. Such efforts may enhance our ability to predict effects on wild populations, including threatened and endangered species.

  19. Identification of three Iranian species of the genus Rattus (Rodentia, Muridae using a PCR-RFLP technique on mitochondrial DNA

    Directory of Open Access Journals (Sweden)

    safieh Akbary rad

    2009-11-01

    Full Text Available Abstract Three species of the genus Rattus Fisher, 1803 have been reported from Iran: the brown rat (R. norvegicus, the black rat (R. rattus and the Himalayan rat (R. pyctoris. The first two were introduced, whilst R. pyctoris is native and lives in mountainous regions from Pakistan to north-eastern Iran. In this study, the mitochondrial DNA from twenty six rats were analysed using a PCR-RFLP (Polymerase Chain Reaction - Restriction Fragments Length Polymorphism method to investigate inter-specific variation. Part of the 16S rRNA and cytochrome b genes were amplified and digested with three restriction enzymes: AluI, MboI and HinfI. Restriction fragments resulted in four different haplotypes and allowed to distinguish the three Rattus species. Our results suggest that the Himalayan rats are more closely related to R. rattus than to R. norvegicus and provide the basics for further phylogenetic studies. Riassunto Identificazione di tre specie iraniane del genere Rattus (Rodentia, Muridae tramite PCR-RFLP su DNA mitocondriale. Tre specie del genere Rattus risultano diffuse in Iran: il surmolotto (R. norvegicus, il ratto nero (R. rattus e il ratto himalayano (R. pyctoris. Le prime due specie sono state introdotte, mentre R. pyctoris è presente nelle aree montane che si sviluppano dal Pakistan all’Iran nordorientale. In questo studio, il DNA mitocondriale di 26 individui è stato analizzato tramite PCR-RFLP per evidenziare variazioni inter-specifiche. Parte dei geni del rRNA 16S e del citocromo b è stata amplificata e quindi sottoposta a digestione tramite tre diversi enzimi: AluI, MboI e HinfI. I frammenti di restrizione hanno permesso di individuare quattro aplotipi mitocondriali e di distinguere le tre specie. I risultati ottenuti suggeriscono che il ratto

  20. New species and new records of mites of the genus Stigmaeus(Acari: Prostigmata: Stigmaeidae) from Crimea.

    Science.gov (United States)

    Khaustov, Alexander A

    2014-05-06

    Three new species of the genus Stigmaeus Koch, 1836 (Acari: Stigmaeidae) are described from various habitats in Crimea: Stigmaeus kuznetsovi sp. nov. from nests of Microtus socialis (Rodentia: Cricetidae); S. mitrofanovi sp. nov. from galleries of Pityogenes bistridentatus (Coleoptera: Curculionidae) under the bark of Pinus pallasiana, and S. silvestris sp. nov. from rotten log of Pinus pallasiana. Stigmaeus corticeus Kuznetsov and Wainstein, 1977 and S. maraghehiensis Bagheri and Ueckermann, 2012 are recorded for the first time in Crimea. A key to species of the genus Stigmaeus of Crimea is provided.

  1. ASPECTOS ECOLOGICOS DE UNA POBLACION DE ROEDORES EN LA CORDILLERA ORIENTAL COLOMBIANA

    OpenAIRE

    2013-01-01

    Distribution, abundancy, demographic structure, type of spatial pattems and home range of a population ofThomasomys laniger (Thomas, 1895) (RODENTIA: CRICETIDAE) from Valledel Frailejón (Frailejon valley) in Chingaza Natural National Park, on the Oriental mountain chain (cordillera Oriental) in Department of Cundinamarca, were studied from January to December of 1992.· The variation ofthe population pattems according to seasonality based on frecuency of capture ofmice in diferent trapping pha...

  2. Range expansion of Oligoryzomys longicaudatus (Rodentia, Sigmodontinae in Patagonian Chile, and first record of Hantavirus in the region Ampliación del rango de distribución de Oligoryzomys longicaudatus (Rodentia, Sigmodontinae en la Patagonia de Chile y primer registro de Hantavirus en la región

    Directory of Open Access Journals (Sweden)

    SEBASTIÁN BELMAR-LUCERO

    2009-06-01

    Full Text Available At present, 20 species of Oligoryzomys (Rodentia, Sigmodontinae are recognized in the Neotropical region, most of them distinguished by their karyotypes, which fluctuates between 46-70 chromosomes. Two species are currently recognized in Chile, Oligoryzomys longicaudatus (Bennet, 1832; "colilargo" or the long-tailed pygmy rice rat; 2n = 56, which ranges from 27° to approximately 51° S, and O. magellanicus (Bennet, 1836; Magellanic pygmy rice rat; 2n = 54, south of 51° S in the Patagonian region of Chile and Argentina. As part of an ongoing research on the southern Patagonia of Chile, we report the results of small mammal samplings in six localities. We karyotyped 28 specimens and we also sequenced the hypervariable mtDNA region I in 22 individuals, aligning these sequences with an under development phylogeny of O. longicaudatus. We also evaluated the serology and viral charge in all captured specimens to detect the presence of antibodies to Andes virus (ANDV through Strip Immunoblot Assay (SIA, and of viral genome by RT-PCR. The results consistently showed that the karyotype of southern Patagonia specimens was 2n = 56, equal to that of O. longicaudatus, and that individuals from this area do not differentiate phylogenetically from those of the northern range of distribution. In addition, the serology showed the presence of antibodies IgG anti-ANDV and of viral genome in heart, kidney, spleen, and lungs of a single specimen of Oligoryzomys from the locality of Fuerte Bulnes in the Magallanes region. We conclude that all specimens trapped south of 51° S correspond to Oligoryzomys longicaudatus, thus expanding the distribution of this specie! from 51° to at least 55° S. The results also extended the disiribution of the Andes strain of Hantavirus to southernmost Patagonia.Actualmente se reconocen 20 especies de Oligoryzomys (Rodentia, Sigmodontinae en la región Neotropical, la mayoría de ellas distinguidas por sus cariotipos, los que fluct

  3. New species and records of mites of the superfamily Sarcoptoidea (Acariformes: Psoroptidia) from mammals in Brazil.

    Science.gov (United States)

    Bochkov, Andre V; Valim, Michel P

    2016-01-01

    Sixteen species of the superfamily Sarcoptoidea (Acariformes: Psoroptidia) belonging to 10 genera of the families Atopomelidae, Listrophoridae, Chirodiscidae, and Listropsoralgidae are recorded in Brazil. Among them, three species, Prolistrophorus hylaeamys sp. nov. from Hylaeamys laticeps (Lund, 1840) (Cricetidae: Sigmodontinae) from Minas Gerais, Lynxacarus serrafreirei sp. nov. from Galictis cuja (Molina, 1782) (Carnivora: Mustelidae) from Rio de Janeiro (Listrophoridae), and Didelphoecius micoureus sp. nov. (Atopomelidae) from Micoureus paraguayanus (Tate, 1931) (Didelphimorphia: Didelphidae) from Minas Gerais are described as new for science. Three species of the family Listrophoridae, Prolistrophorus bidentatus Fain et Lukoschus, 1984 from Akodon cursor (Winge, 1887) (Rodentia: Cricetidae) (new host), Prolistrophorus ctenomys Fain, 1970 from Ctenomys torquatus Lichtenstein, 1830 (Rodentia: Ctenomyidae) (new host), and Leporacarus sylvilagi Fain, Whitaker et Lukoschus, 1981 from Sylvilagus brasiliensis (Linnaeus, 1758) (Lagomorpha: Leporidae) (new host) -from Minas Gerais and Rio Grande do Sul, and one species of the family Chirodiscidae, Parakosa tadarida McDaniel and Lawrence, 1962 from Molossus molossus (Pallas, 1766) (Chiroptera: Molossidae) are recorded for the first time in Brazil. The previously unknown female of Didelphoecius validus Fain, Zanatta-Coutinho et Fonseca, 1996 (Atopomelidae) from Metachirus nudicaudatus (Geoffroy, 1803) (Didelphimorphia: Didelphidae) from Minas Gerais is described. All data on host-parasite associations of sarcoptoids in Brazil are summarized. Totally, 61 sarcoptoid species of 8 families are recorded in Brazil.

  4. Seasonal effects on the hematology and blood plasma proteins of two species of mice Mus musculus domesticus and M. spretus (Rodentia: Muridae from Portugal

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    António Mira

    1994-05-01

    Full Text Available Abstract Blood samples were taken from Mus musculus domesticus (Rutty, 1772 and M. spretus (Lataste, 1883, live-trapped at one month intervals, from September 88 to July 89, in the district of Lisbon, Portugal. The seasonal hematological variations in the commensal species, M. musculus domesticus, were characterized by an increase in red blood cells, hemoglobin and hematocrit values in winter which reverse during summer. On the contrary, in M. spretus hematocrit values slightly change throughout the year. In both species the albumin/globulin ratio was low in spring and high in autumn. These results were analysed and discussed taking into account environmental factors and physiological conditions of mice. Riassunto Effetti stagionali sull'ematologia e le proteine del plasma di Mus musculus domesticus e M. spretus (Rodentia: Muridae in Portogallo - I campioni di sangue provengono da individui di Mus musculus domesticus (Rutty, 1772 e M. spretus (Lataste, 1883. Gli animali sono stati catturati vivi ogni mese, da settembre 88 a luglio 89, nel distretto di Lisbona, in Portogallo. Le variazioni stagionali ematologiche nella specie commensale, M. m. domesticus, sono caratterizzate da un incremento di cellule rosse del sangue, di emoglobina e dei valori di ematocrito in inverno che assumono un andamento opposto in estate. Al contrario, in M. spretus i valori di ematocrito non cambiano sensibilmente durante tutto l'anno. In entrambe le specie il rapporto albumina/globulina risulta basso in primavera e alto in autunno. Questi risultati sono stati analizzati e discussi tenendo conto dei fattori ambientali e le condizioni fisiologiche dei topi.

  5. A glimpse on the pattern of rodent diversification

    DEFF Research Database (Denmark)

    Fabre, Pierre-Henri Fréderic; Hautier, Lionel; Dimitrov, Dimitar Stefanov;

    2012-01-01

    a rodent maximum likelihood phylogeny inferred from a molecular supermatrix. It is based on 11 mitochondrial and nuclear genes that covers 1,265 species, i.e., respectively 56% and 81% of the known specific and generic rodent diversity. The inferred topology recovered all Rodentia clades proposed by recent...... in diversification rates within the major clades: two in Castorimorpha, three in Ctenohystrica, 6 within the squirrel-related clade and 24 in the Myomorpha clade. The majority of these shifts occurred within the most recent familial rodent radiations: the Cricetidae and Muridae clades. Using the topological...... imbalances and the time line we discuss the potential role of different diversification factors that might have shaped the rodents radiation. CONCLUSIONS:The present glimpse on the diversification pattern of rodents can be used for further comparative meta-analyses. Muroid lineages have a greater degree...

  6. The complete mitochondrial genome of lesser long-tailed Hamster Cricetulus longicaudatus (Milne-Edwards, 1867) and phylogenetic implications.

    Science.gov (United States)

    Zhang, Ziqi; Sun, Tong; Kang, Chunlan; Liu, Yang; Liu, Shaoying; Yue, Bisong; Zeng, Tao

    2016-01-01

    The complete mitochondrial genome sequence of Cricetulus longicaudatus (Rodentia Cricetidae: Cricetinae) was determined and was deposited in GenBank (GenBank accession no. KM067270). The mitochondrial genome of C. longicaudatus was 16,302 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and one control region, with an identical order to that of other rodents' mitochondrial genomes. The phylogenetic analysis was performed with Bayesian inference based on the concatenated nucleotide sequence of 12 protein-coding genes on the heavy strand. The result showed that these species from Cricetidae and its two subfamilies (Cricetinae and Arvicolines) formed solid monophyletic group, respectively. The Cricetulus had close phylogenetic relationship with Tscherskia among three genera (Cricetulus, Cricetulus and Mesocricetus). Neodon irene and Myodes regulus were embedded in Microtus and Eothenomys, respectively. The unusual phylogenetic positions of Neodon irene and Myodes regulus remain further study in the future.

  7. Ocular comparative anatomy of the family Rodentia.

    Science.gov (United States)

    Rodriguez-Ramos Fernandez, Julia; Dubielzig, Richard R

    2013-07-01

    There is little information regarding ocular anatomy and histology in many of the rodent species. Histological analyses for morphologic features were performed in 31 globes from 18 rodent species submitted to and archived at the Comparative Ocular Pathology Laboratory of Wisconsin. The following measurements were taken: thickness of the cornea, corneal epithelium, corneal stroma, Descemet's membrane, and retina. H&E sections were evaluated for the following anatomical features: presence of pigmented epithelial cells in the peripheral cornea, presence and location of Schlemm's canal, presence of iridal sphincter and dilator and ciliary body muscles, presence of pars plicata and plana, presence of retinal vessels, presence of lamina cribrosa, and presence of tapetum lucidum. The springhaas was the only rodent in our collection that presented a well-developed tapetum lucidum fibrosum. The presence of retinal vessels was variable: vessels were observed in all of the members of the mouse-related clade, except the springhaas and the beaver, in all of the squirrel-related clade members, and in none of the Ctenohystrica. In the flying squirrels, blood vessels extended to the outer limiting membrane in the photoreceptor layer. Beavers, chinchillas, capybara, and guinea pigs lacked vessels within the retina; however, they had vessels within the optic nerve head. Ground squirrels have an optic nerve head, which is linear in the horizontal plane and an asymmetric retina. The tree-dwelling squirrels have a rounded but still elongated optic nerve, and the flying squirrel has a round optic nerve head like all the other rodents.

  8. A new karyotype of Calomys (Rodentia, Sigmodontinae

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    Lima J. Fernando de S.

    2001-01-01

    Full Text Available The genus Calomys Waterhouse, 1837 is widely distributed within South America, being found in Venezuela, Colombia, Peru, Bolivia, Brazil, Paraguay, Uruguay and Argentina. Specimens of Calomys were collected in Formoso do Araguaia, Tocantins, Brazil. For chromosome characterization standard staining techniques and as G-banding and nucleolar organizer region were used. The karyotype was 2n=46 and AN=66. The X chromosome is a medium metacentric and the Y chromosome a small acrocentric chromosome. Chromosome homologies with other species were observed. Probably, karyotype differences were basically due to Robertsonian rearrangements.

  9. Historia natural de un roedor raro del desierto argentino, Salinomys delicatus (Cricetidae: Sigmodontinae Natural history of a rare rodent of the Argentinean desert, Salinomys delicatus(Cricetidae: Sigmodontinae

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    DANIELA RODRÍGUEZ

    2012-03-01

    Full Text Available El ratón delicado de los salares (Salinomys delicatus es un pequeño roedor endémico de Argentina. Ha sido considerado como vulnerable a la extinción dada su distribución restringida y en parches, tamaño poblacional pequeño y especialización en hábitats salinos. A pesar de que el ratón delicado tiene adaptaciones morfológicas y fisiológicas para la supervivencia en ambientes áridos y salitrosos, poco es lo que se conoce de su historia natural. El presente trabajo tiene como objetivo estudiar la historia natural de S. delicatus, reportar nuevas localidades de ocurrencia, caracterizar el uso de hábitat, su dieta y el ensamble acompañante, y describir su biología reproductiva y morfología. Se registraron dos nuevos sitios de ocurrencia en ambientes de bosques en galería y bajos salinos en la región noreste de la provincia de Mendoza (Argentina, siendo las primeras citas para esta provincia. S. delicatus presenta una dieta omnívora, como es frecuente en otros roedores de desierto, y consume en igual medida semillas, artrópodos y plantas halófitas. El ensamble acompañante está compuesto por no más de tres especies de pequeños mamíferos que varían según la localidad, siendo esta riqueza similar a otros sitios del Monte. La proporción de sexos y el patrón de dimorfismo sexual mostraron un marcado desvío hacia las hembras (H:M = 3.6:1.1 y H:M = 1.151 respectivamente. La morfología externa y craneal presenta una importante variabilidad intra e interpoblacional, sugiriendo que el aislamiento juega un rol importante. Cuando se consideraron adultos y juveniles, conjuntamente dos de las seis medidas externas (longitud total y longitud de cabeza y cuerpo y siete de las 22 medidas craneales resultaron significativamente mayores en hembras que en machos. Cuando se compararon solo los adultos, cuatro características externas (longitud total, longitud de cabeza y cuerpo, largo de la cola y peso y seis medidas craneales fueron significativamente mayores en hembras que en machos. Este trabajo refuerza la importancia del desarrollo de nuevos estudios más detallados sobre la historia de vida de S. delicatus y permite reafirmar la importancia de conservación de esta especie.The delicate mouse (Salinomys delicatus is a small rodent endemic of Argentina. It has been considered vulnerable to extinction because of its restricted and patchy distribution, small population size and specialization on salty habitats. Besides its morphological and physiological adaptations to survive in arid and salty habitats, there is still little information about the natural history of the delicate mouse. The objectives of our study are to study the natural history of S. delicatus, report new localities of occurrence, characterize its habitat use, diet and accompanying assemblages and describe its reproductive biology and morphology. We report two new localities of occurrences in gallery woodlands and salt flats in the northeast of Mendoza province (Argentina, these being the first records for this province. Like other South AAmerican rodents, S. delicatus has an omnivorous diet consisting in similar proportion of seeds, arthropods and halophytic plants. The assemblages are composed by no more than three small mammal species, varying according to the locality. Sex ratio and the pattern of sexual dimorphism shows a strong bias towards females (H:M = 3.6:1.1 and H:M = 1.151 respectively. External and cranial morphology exhibits a clear intra- and inter-population variability. When considering in the analysis adults and juvenile, two of six external measurements (head and body length and total length and seven of twenty-two cranial measurements were significantly higher in females than in males. When considering only adults, four external measures (total length, head and body length, tail length and weight and six cranial measurements were significantly higher in females than in males. This integrative analysis highlights the relevance of conducting further and more detailed studies on the natural history of S. delicatus and allows us to reassert the conservation importance of this species.

  10. First record of Pseudoryzomys simplex (Cricetidae, Sigmodontinae in a flooded area of the Pantanal, Brazil

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    R. W. Wolf

    Full Text Available Abstract Pseudoryzomys simplex is a small to medium sized terrestrial rodent confined to lowland open areas with strong seasonal rainfall throughout the Chaco, Cerrado and Caatinga. Despite its extensive range, the species is difficult to trap. In this report we provide the first record of P. simplex in the Pantanal, where three specimens were collected in a pasture of exotic grass. The specimens are morpometrically similar to the population from Paraguay (Chaco. In this sense, our report shows how interesting a taxonomic review of the species would be to better understand the real significance of the geographic variation herein observed.

  11. Preliminary investigation of rodents and storage host of pathogen of Lyme disease in Shanxi%陕西省啮齿动物与莱姆病病原贮存宿主的初步调查

    Institute of Scientific and Technical Information of China (English)

    李志清; 罗芳; 刘增加; 费晋秀; 郭宏林

    2011-01-01

    Objective To investigation the rodents and storage host of pathogen of Lyme disease in Shannxi prov-ince. Method Adopting clip night method and Lyme disease BSK - II pathogen separated and cultivated. Results This ar-ticle described the already know 56 species 35 genera and 7 families rodentia, among them, Sciuridae 6 species 6 genera, Pteromyidae 4 species 2 genera, Dipididae 5 species 5 genera, Platacanthomyidae 1 species 1 genera, Spalacidae 6 spe-cies 2 genera, Cricetidae 16 species 12 genera, Muridae 18 species 7 genera. We separated and cultivated a strain of Lyme disease Borrelia burgdorferi From Niviventer confucianus Hodgson. Conclusions Preliminary mastered the rodents and po-tential storage host of pathogen of Lyme disease in Shannxi province.%目的 调查陕西省的啮街动物与莱姆病病原的贮存宿主.方法 夹夜法和莱姆病病原的BSK-Ⅱ培养分离.结果 记述啮齿目Rodentia已知7科35届56种,其中松鼠科Sciuridae 6属6种,鼯鼠科Pteromyidae 2届4种,跳鼠科Dipididae 5属5种,刺山鼠科Platacanthomyidae 1属1种,鼹形鼠科Spalacidae 2属6种,仓鼠科Cricetidae 12属16种,鼠科Muridae 7属18种.从社鼠Niviventer confucianus Hodgson体内培养分离出1株莱姆病伯氏疏螺旋体.结论 初步掌握了陕西省啮齿动物与莱姆病病原的潜在贮存宿主.

  12. Late Pleistocene voles (Arvicolinae, Rodentia) from the Baranica Cave (Serbia)

    Science.gov (United States)

    Bogićević, Katarina; Nenadić, Draženko; Mihailović, Dušan

    2012-02-01

    Baranica is a cave system situated in the south-eastern part of Serbia, four kilometers south to Knjaževac, on the right bank of the Trgovi\\vski Timok. The investigations in Baranica were conducted from 1994 to 1997 by the Faculty of Philosophy from Belgrade and the National Museum of Knjaževac. Four geological layers of Quaternary age were recovered. The abundance of remains of both large and small mammals was noticed in the early phase of the research. In this paper, the remains of eight vole species are described: Arvicola terrestris (Linnaeus, 1758), Chionomys nivalis (Martins, 1842), Microtus (Microtus) arvalis (Pallas, 1778) and Microtus (Microtus) agrestis (Linnaeus, 1761), Microtus (Stenocranius) gregalis (Pallas, 1779), Microtus (Terricola) subterraneus (de Sélys-Longchamps, 1836), Clethrionomys glareolus (Schreber, 1780) and Lagurus lagurus (Pallas, 1773). Among them, steppe and open area inhabitants prevail. Based on the evolutionary level and dimensions of the Arvicola terrestris molars, as well as the overall characteristics of the fauna, it was concluded that the deposits were formed in the last glacial period of the Late Pleistocene. These conclusions are rather consistent with the absolute dating of large mammal bones (23.520 ± 110 B.P. for Layer 2 and 35.780 ± 320 B.P. for Layer 4).

  13. Dietary ecology of Murinae (Muridae, Rodentia): a geometric morphometric approach.

    Science.gov (United States)

    Gómez Cano, Ana Rosa; Hernández Fernández, Manuel; Alvarez-Sierra, M Ángeles

    2013-01-01

    Murine rodents represent a highly diverse group, which displays great ecological versatility. In the present paper we analyse the relationship between dental morphology, on one hand, using geometric morphometrics based upon the outline of first upper molar and the dietary preference of extant murine genera, on the other. This ecomorphological study of extant murine rodents demonstrates that dietary groups can be distinguished with the use of a quantitative geometric morphometric approach based on first upper molar outline. A discriminant analysis of the geometric morphometric variables of the first upper molars enables us to infer the dietary preferences of extinct murine genera from the Iberian Peninsula. Most of the extinct genera were omnivore; only Stephanomys showed a pattern of dental morphology alike that of the herbivore genera.

  14. Dietary ecology of Murinae (Muridae, Rodentia: a geometric morphometric approach.

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    Ana Rosa Gómez Cano

    Full Text Available Murine rodents represent a highly diverse group, which displays great ecological versatility. In the present paper we analyse the relationship between dental morphology, on one hand, using geometric morphometrics based upon the outline of first upper molar and the dietary preference of extant murine genera, on the other. This ecomorphological study of extant murine rodents demonstrates that dietary groups can be distinguished with the use of a quantitative geometric morphometric approach based on first upper molar outline. A discriminant analysis of the geometric morphometric variables of the first upper molars enables us to infer the dietary preferences of extinct murine genera from the Iberian Peninsula. Most of the extinct genera were omnivore; only Stephanomys showed a pattern of dental morphology alike that of the herbivore genera.

  15. Pericentric satellite DNA and molecular phylogeny in Acomys (Rodentia).

    Science.gov (United States)

    Kunze, B; Traut, W; Garagna, S; Weichenhan, D; Redi, C A; Winking, H

    1999-01-01

    Satellite DNAs (stDNAs) of four Acomys species (spiny-mice), A. cahirinus, A. cineraceus, A. dimidiatus and A. russatus, belong to closely related sequence families. Monomer sizes range from 338 to 364 bp. Between-species sequence identity was from 81.0% to 97.2%. The molecular phylogeny of the sequences helps to clarify the taxonomy of this 'difficult' group. The A. dimidiatus genome contains about 60000 repeats. According to the restriction patterns, repeats are arranged in tandem. The stDNA maps to the centromeric heterochromatin of most autosomes, both acrocentric and metacentric, but appears to be absent in the centromeric region of Y chromosomes. A well-conserved centromere protein B (CENP-B) box is present in the stDNA of A. russatus while it is degenerated in the other species.

  16. [Ovarian activity of Agouti paca (Rodentia: Agoutidae) under captivity].

    Science.gov (United States)

    Montes Pérez, Rubén C; Cabrera Baz, Elsy A

    2006-09-01

    The ovarian activity of Agouti paca was characterized by hormonal profiles and ovarian structures. Samples of blood were taken from eight females (seven adults and one juvenile) at the breeding grounds of the Facultad de Medicina Veterinaria y Zootecnia in Yucatśn, Mexico. Sampling lasted approximately two months and was done every three and six days. Blood was collected from anesthetized animals, and the levels of progesterone (P4) and 17 beta estradiol (E2) were analized by radioimmunoassay technique. Macroscopic and microscopic analyses were carried out in ovaries of dead animals. The estrous cycle lasted 29+/-8.4 days, levels of 1.61+/-0.65 ng/ml for P4 and 39+/-24 pg/ml for E2 were observed for a follicular phase, 6.18+/-3.70 ng/ml and 29+/-16 pg/ml for P4 and E2 respectively in the luteal phase. Statistically significant differences were found between phases for P4 but not for E2. The presence of extragonadal steroids with levels of P4 of 1.9+/-0.77 ng/ml and E2 of 22+/-17 pg/ml were observed, which are not produced by the effects of managing stress. The changes in the levels of P4 during the cycle are indicators of luteal activity, with the intersticial tissue acting probably as active steroids-producing gland. Follicular growth was observed during the entire cycle.

  17. Phylogeographic study of Apodemus ilex (Rodentia: Muridae in Southwest China.

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    Qi Liu

    Full Text Available BACKGROUND: The Mountains of southwest China have complex river systems and a profoundly complex topography and are among the most important biodiversity hotspots in the world. However, only a few studies have shed light on how the mountains and river valleys promote genetic diversity. Apodemus ilex is a fine model for investigating this subject. METHODOLOGY/PRINCIPAL FINDINGS: To assess the genetic diversity and biogeographic patterns of Apodemus ilex, the complete cytochrome b gene sequences (1,140 bp were determined from 203 samples of A. draco/ilex that were collected from southwest China. The results obtained suggested that A. ilex and A. draco are sistergroups and diverged from each other approximately 2.25 million years ago. A. ilex could be divided into Eastern and Western phylogroups, each containing two sub-groups and being widespread in different geographical regions of the southern Hengduan Mountains and the western Yunnan - Guizhou Plateau. The population expansions of A. ilex were roughly from 0.089 Mya to 0.023 Mya. CONCLUSIONS: Our result suggested that A. ilex is a valid species rather than synonym of A. draco. As a middle-high elevation inhabitant, the phylogenetic pattern of A. ilex was strongly related to the complex geographical structures in southwest China, particularly the existence of deep river valley systems, such as the Mekong and Salween rivers. Also, it appears that the evolutionary history of A. ilex, such as lineage divergences and population expansions were strongly affected by climate fluctuation in the Late Pleistocene.

  18. First report of partial albinism in genus Thrichomys (Rodentia: Echimyidae

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    Antonio Carlos da S.A. Neves

    2014-01-01

    Full Text Available Reports about albinism in rodents are common. In the family Echimyidae, however, albinism is very rare. This is the second case of coat color variation reported within Echimyidae and the first for the genus Thrichomys. The pelages of Thrichomys pachyurus individuals with normal and variant coat color were observed under a fluorescent artificial light and were examined with a stereoscopic microscope. The descriptions of pelage color were based on the book "Color Standards and Color Nomenclature". The predominantly white pattern of coat color in individuals of T. pachyurus suggests a partial albinism caused by delay in migration time of melanoblasts from neural crest to epidermis. The habitat of T. pachyurus has a heavy vegetative cover, which offers natural protection against predators and high-quality nutrition.

  19. RAPD analysis of Nectomys squamipes (Rodentia, Sigmodontinae populations

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    Almeida Francisca C.

    2000-01-01

    Full Text Available Random amplified of polymorphic DNA (RAPD analysis was used to assess genetic distance and the genetic structure of populations of Nectomys squamipes, a semiaquatic rodent species distributed along watercourses. DNA samples of five populations were analyzed using three primers, producing 45 scorable bands, 31 of which were polymorphic. There was a significant differentiation among populations [F ST = 0.17; phiST = 0.14 (P < 0.004] but gene flow (Nm = 1.25 was sufficient to overcome genetic drift effects. No fixed specific markers were found for any population. The Mantel's test and UPGMA cluster analysis showed a lack of relationship between genetic and geographic distances. The apparent homogeneity indicated by RAPD markers coincided with morphometric data, despite the wide geographic range of N. squamipes. Alternative hypotheses for explaining our results include recurrent processes of local extinction and recolonization or a recent and sudden increase in the geographic distribution of this species.

  20. Children's Attitudes towards Animals: Evidence from the RODENTIA Project

    Science.gov (United States)

    Fonseca, Maria Joao; Franco, Nuno H.; Brosseron, Francis; Tavares, Fernando; Olsson, I. Anna S.; Borlido-Santos, Julio

    2011-01-01

    The instructional use of animals is a popular strategy to engage students with science, enhance their motivation, and promote values such as respect, tolerance, and empathy for all living beings. Although these beneficial outcomes are widely acknowledged, research has not provided reliable indicators of their efficiency. Therefore, it is essential…

  1. Spatial patterns in Mastomys natalensis in Tanzania (Rodentia, Muridae)

    DEFF Research Database (Denmark)

    Leirs, Herwig; Verheyen, Walter; Verhagen, Ron

    1996-01-01

    in periods without reproduction, indicated a high degree of dispersal. Resident animals had a limited home range with most movements within 30 m of the burrow; however, excursions and movements over large distances were observed. Animals living on the border of maize fields and fallow land are active in both...

  2. Late Pleistocene echimyid rodents (Rodentia, Hystricognathi) from northern Brazil.

    Science.gov (United States)

    Ferreira, Thais M F; Olivares, Adriana Itati; Kerber, Leonardo; Dutra, Rodrigo P; Avilla, Leonardo S

    2016-06-07

    Echimyidae (spiny rats, tree rats and the coypu) is the most diverse family of extant South American hystricognath rodents (caviomorphs). Today, they live in tropical forests (Amazonian, coastal and Andean forests), occasionally in more open xeric habitats in the Cerrado and Caatinga of northern South America, and open areas across the southern portion of the continent (Myocastor). The Quaternary fossil record of this family remains poorly studied. Here, we describe the fossil echimyids found in karst deposits from southern Tocantins, northern Brazil. The analyzed specimens are assigned to Thrichomys sp., Makalata cf. didelphoides and Proechimys sp. This is the first time that a fossil of Makalata is reported. The Pleistocene record of echimyids from this area is represented by fragmentary remains, which hinders their determination at specific levels. The data reported here contributes to the understanding of the ancient diversity of rodents of this region, evidenced until now in other groups, such as the artiodactyls, cingulates, carnivores, marsupials, and squamate reptiles.

  3. Late Pleistocene echimyid rodents (Rodentia, Hystricognathi from northern Brazil

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    THAIS M.F. FERREIRA

    2016-06-01

    Full Text Available ABSTRACT Echimyidae (spiny rats, tree rats and the coypu is the most diverse family of extant South American hystricognath rodents (caviomorphs. Today, they live in tropical forests (Amazonian, coastal and Andean forests, occasionally in more open xeric habitats in the Cerrado and Caatinga of northern South America, and open areas across the southern portion of the continent (Myocastor. The Quaternary fossil record of this family remains poorly studied. Here, we describe the fossil echimyids found in karst deposits from southern Tocantins, northern Brazil. The analyzed specimens are assigned to Thrichomys sp., Makalata cf. didelphoides and Proechimys sp. This is the first time that a fossil of Makalata is reported. The Pleistocene record of echimyids from this area is represented by fragmentary remains, which hinders their determination at specific levels. The data reported here contributes to the understanding of the ancient diversity of rodents of this region, evidenced until now in other groups, such as the artiodactyls, cingulates, carnivores, marsupials, and squamate reptiles.

  4. Spontaneous expression of magnetic compass orientation in an epigeic rodent: the bank vole, Clethrionomys glareolus

    Science.gov (United States)

    Oliveriusová, Ludmila; Němec, Pavel; Pavelková, Zuzana; Sedláček, František

    2014-07-01

    Magnetoreception has been convincingly demonstrated in only a few mammalian species. Among rodents, magnetic compass orientation has been documented in four species of subterranean mole rats and two epigeic (i.e. active above ground) species—the Siberian hamster and the C57BL/6J mouse. The mole rats use the magnetic field azimuth to determine compass heading; their directional preference is spontaneous and unimodal, and their magnetic compass is magnetite-mediated. By contrast, the primary component of orientation response is learned in the hamster and the mouse, but both species also exhibit a weak spontaneous bimodal preference in the natural magnetic field. To determine whether the magnetic compass of wild epigeic rodents features the same functional properties as that of laboratory rodents, we investigated magnetic compass orientation in the bank vole Clethrionomys glareolus (Cricetidae, Rodentia). The voles exhibited a robust spontaneous bimodal directional preference, i.e. built nests and slept preferentially along the north-south axis, and deflected their directional preference according to a shift in the direction of magnetic north, clearly indicating that they were deriving directional information from the magnetic field. Thus, bimodal, axially symmetrical directional choice seems to be a common feature shared by epigeic rodents. However, spontaneous directional preference in the bank vole appeared to be more pronounced than that reported in the hamster and the mouse. These findings suggest that bank voles are well suited for future studies investigating the adaptive significance and mechanisms of magnetic orientation in epigeic rodents.

  5. Calomys callosus: an alternative model to study fibrosis in Schistosomiasis mansoni: the pathology of the acute phase

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    J. A. Lenzi

    1995-04-01

    Full Text Available Twenty Calomys callosus, Rengger, 1830 (Rodentia-Cricetidae were studied in the early stage of the acute schistosomal mansoni infection (42nd day. The same number of Swiss Webster mice were used as a comparative standard. Liver and intestinal sections, fixed in formalin-Millonig and embedded in paraffin, were stained with hematoxilin and eosin, PAS-Alcian Blue, pH = 1.0 and 2.5, Lennert's Giemsa, Picrosirius plus polarization microscopy, Periodic acid methanamine silver, Gomori's silver reticulin and resorcin-fuchsin. Immunohistological study (indirect immunofluorescence and peroxidase labeled extravidin-biotin methods was done with antibodies specific to pro-collagen III, fibronectin, elastin, condroitin-sulfate, tenascin, alpha smooth muscle actin, vimentin and desmin. The hepatic granulomas were small, reaching only 27 of the volume of the hepatic Swiss Webster granuloma. They were composed mainly by large immature macrophages, often filled by schistosomal pigment, characterizing an exsudative-macrophage granuloma type. The granulomas were situated in the parenchyma and in the portal space. They were often intravascular, poor of extracellular matrix components, except fibronectin and presented, sometimes alpha smooth muscle actin and vimentin positive cells. The C. callosus intestinal granulomas were similar to Swiss Webster, showing predominance of macrophages. Therefore, the C. callosus acquire very well the Schistosoma mansoni infection, without developing strong hepatic acute granulomatous reaction, suggesting lack of histopathological signs of hypersensitivity.

  6. Nests of the Brazilian squirrel Sciurus ingrami Thomas (Rodentia, Sciuridae Ninhos do esquilo brasileiro Sciurus ingrami Thomas (Rodentia, Sciuridae

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    Cibele A. Alvarenga

    2005-09-01

    Full Text Available Descriptions of Sciurus ingrami Thomas, 1901 nests are not available in the literature. In this study, a survey was made of the distribution of S. ingrami nests in a woodlot located near to the headquarters of the Serra do Caraça Reserve, in state of Minas Gerais, where there is a high concentration of Syagrus romanzoffiana (Chamisso Glassman palm tree, among other exotic tree species. The nest-building behaviour and the nest characteristics, such as height from the ground, total circumference, diameter of the entrance, and the position of the nest in the tree - in the crown, along the trunk or in a side branch, were described.Não existe na literatura a descrição de ninhos de Sciurus ingrami Thomas, 1901. Neste estudo, foi examinada a distribuição espacial de ninhos desta espécie, localizados em área de vegetação de crescimento secundário, próxima a área construída da Reserva Particular do Patrimônio Natural Serra do Caraça, Minas Gerais, onde há grande concentração da palmeira Syagrus romanzoffiana (Chamisso Glassman, entre outras espécies exóticas de árvores. O comportamento de construção e as características dos ninhos, tais como, altura em relação ao solo, circunferência total, diâmetro da entrada e a posição dos ninhos na árvore foram descritos.

  7. Micromammals (Insectivora; Rodentia of "Valle dell'Inferno" (Rome / Micromammiferi (Insectivora; Rodentia della Valle dell'Inferno (Roma

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    Roberto Federici

    1986-12-01

    Full Text Available Abstract A research on micromammals in the area of "Valle dell'Inferno" (in the north-west of Rome was carried out. The study was based on a previous phytosociological survey which describes a Quercus suber population in the valley (a once larger residua1 of a roman cork-tree wood which is now included in the town. Specimens from Rodents (Apodemus sylvaticus, Mus domesticus, Rattus rattus, R. norvegicus, Pitymys savii and Insectivores (Crocidura suaveolens, Erinaceus europaeus were captured by live traps. Most of Insectivores specimens are represented by C. suaveolens. Generally C. suaveolens lives in sympatry with C. leucodon but no specimens of the latter were found in this area. Three different kinds of landscape are present in the "Inferno" valley, namely, the wood, the meadow, and the bottom valley (with high anthropic impact; we have compared these three landscapes with biotic indexes (index of faunistic affinity, index of biocoenotic affinity and index of environmental evaluation. We have also compared through the same indexes, the micromammal fauna of the "Inferno" valley with six other differently polluted localities in Latium, where animals were captured with the same live traps. This area retains its natura1 environment in despite of the high anthropic impact. Riassunto È stato effettuato uno studio sulla micromammalofauna terrestre della Valle dell'Inferno situata a nord-ovest di Roma. Lo studio è basato su una precedente indagine fitosociologica effettuata per la caratterizzazione vegetazionale di una sughereta un tempo molto estesa ed ora racchiusa nell'abitato cittadino. È stato pertanto possibile tracciare, tramite gli indici biotici, una correlazione tra microteriocenosi ed effetti dell'impatto antropico.

  8. Estudo do roedor Akodon arviculoides, Wagner, 1842 (Cricetidae: importância nos focos pestosos no Brasil The rodent Akodon arviculoides, Wagner, 1842 (Cricetidae: importance in plague focus of Brazil

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    Célio Rodrigues de Almeida

    1986-12-01

    Full Text Available Relata-se a ocorrência do roedor Akodon arviculoides (Wagner, 1842 no foco pestoso do Agreste pernambucano, sua capacidade de sobrevivência, reprodução e o desenvolvimento no cativeiro, a susceptibilidade à infecção pela Yersinia pestis e a importãncia desse roedor nos focos pestosos do Brasil.The occurrence of the rodent Akodon arviculoides Wagner, 1842 in the plague focus of the "Agreste" region of the State of Pernambuco and a report on its ability for survival, reproduction and development in captivity, its susceptibility to Yersinia pestis infection and the role of this rodent species in Brazilian plague foci are reported.

  9. Directory of Open Access Journals (Sweden)

    Camilo Guzmán

    2013-04-01

    Full Text Available We tested sera from 286 agricultural workers and 322 rodents in the department of Córdoba, northeastern Colombia, for antibodies against two hantaviruses. The sera were analysed by indirect ELISA using the lysate of Vero E6 cells infected with Maciel virus (MACV or the N protein of Araraquara virus (ARAV as antigens for the detection of antibodies against hantaviruses. Twenty-four human sera were IgG positive using one or both antigens. We detected anti-MACV IgG antibodies in 10 sera (3.5% and anti-ARAV antibodies in 21 sera (7.34%. Of the 10 samples that were positive for MACV, seven (70% were cross-reactive with ARAV; seven of the 21 ARAV-positive samples were cross-reactive with MACV. Using an ARAV IgM ELISA, two of the 24 human sera (8.4% were positive. We captured 322 rodents, including 210 Cricetidae (181 Zygodontomys brevicauda, 28 Oligoryzomys fulvescens and 1 Oecomys trinitatis, six Heteromys anomalus (Heteromyidae, one Proechimys sp. (Echimyidae and 105 Muridae (34 Rattus rattus and 71 Mus musculus. All rodent sera were negative for both antigens. The 8.4% detection rate of hantavirus antibodies in humans is much higher than previously found in serosurveys in North America, suggesting that rural agricultural workers in northeastern Colombia are frequently exposed to hantaviruses. Our results also indicate that tests conducted with South American hantavirus antigens could have predictive value and could represent a useful alternative for the diagnosis of hantavirus infection in Colombia.

  10. Prevalence of antibody to hantaviruses in humans and rodents in the Caribbean region of Colombia determined using Araraquara and Maciel virus antigens.

    Science.gov (United States)

    Guzmán, Camilo; Mattar, Salim; Levis, Silvana; Pini, Noemí; Figueiredo, Tadeu; Mills, James; Salazar-Bravo, Jorge

    2013-04-01

    We tested sera from 286 agricultural workers and 322 rodents in the department of Córdoba, northeastern Colombia, for antibodies against two hantaviruses. The sera were analysed by indirect ELISA using the lysate of Vero E6 cells infected with Maciel virus (MACV) or the N protein of Araraquara virus (ARAV) as antigens for the detection of antibodies against hantaviruses. Twenty-four human sera were IgG positive using one or both antigens. We detected anti-MACV IgG antibodies in 10 sera (3.5%) and anti-ARAV antibodies in 21 sera (7.34%). Of the 10 samples that were positive for MACV, seven (70%) were cross-reactive with ARAV; seven of the 21 ARAV-positive samples were cross-reactive with MACV. Using an ARAV IgM ELISA, two of the 24 human sera (8.4%) were positive. We captured 322 rodents, including 210 Cricetidae (181 Zygodontomys brevicauda, 28 Oligoryzomys fulvescens and 1 Oecomys trinitatis), six Heteromys anomalus (Heteromyidae), one Proechimys sp. (Echimyidae) and 105 Muridae (34 Rattus rattus and 71 Mus musculus). All rodent sera were negative for both antigens. The 8.4% detection rate of hantavirus antibodies in humans is much higher than previously found in serosurveys in North America, suggesting that rural agricultural workers in northeastern Colombia are frequently exposed to hantaviruses. Our results also indicate that tests conducted with South American hantavirus antigens could have predictive value and could represent a useful alternative for the diagnosis of hantavirus infection in Colombia.

  11. Prevalence of antibody to hantaviruses in humans and rodents in the Caribbean region of Colombia determined using Araraquara and Maciel virus antigens

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    Camilo Guzmán

    2013-04-01

    Full Text Available We tested sera from 286 agricultural workers and 322 rodents in the department of Córdoba, northeastern Colombia, for antibodies against two hantaviruses. The sera were analysed by indirect ELISA using the lysate of Vero E6 cells infected with Maciel virus (MACV or the N protein of Araraquara virus (ARAV as antigens for the detection of antibodies against hantaviruses. Twenty-four human sera were IgG positive using one or both antigens. We detected anti-MACV IgG antibodies in 10 sera (3.5% and anti-ARAV antibodies in 21 sera (7.34%. Of the 10 samples that were positive for MACV, seven (70% were cross-reactive with ARAV; seven of the 21 ARAV-positive samples were cross-reactive with MACV. Using an ARAV IgM ELISA, two of the 24 human sera (8.4% were positive. We captured 322 rodents, including 210 Cricetidae (181 Zygodontomys brevicauda, 28 Oligoryzomys fulvescens and 1 Oecomys trinitatis, six Heteromys anomalus (Heteromyidae, one Proechimys sp. (Echimyidae and 105 Muridae (34 Rattus rattus and 71 Mus musculus. All rodent sera were negative for both antigens. The 8.4% detection rate of hantavirus antibodies in humans is much higher than previously found in serosurveys in North America, suggesting that rural agricultural workers in northeastern Colombia are frequently exposed to hantaviruses. Our results also indicate that tests conducted with South American hantavirus antigens could have predictive value and could represent a useful alternative for the diagnosis of hantavirus infection in Colombia.

  12. Extensive Chromosomal Reorganization in the Evolution of New World Muroid Rodents (Cricetidae, Sigmodontinae): Searching for Ancestral Phylogenetic Traits

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    Pereira, Adenilson Leão; Malcher, Stella Miranda; Nagamachi, Cleusa Yoshiko; O’Brien, Patricia Caroline Mary; Ferguson-Smith, Malcolm Andrew; Mendes-Oliveira, Ana Cristina; Pieczarka, Julio Cesar

    2016-01-01

    Sigmodontinae rodents show great diversity and complexity in morphology and ecology. This diversity is accompanied by extensive chromosome variation challenging attempts to reconstruct their ancestral genome. The species Hylaeamys megacephalus–HME (Oryzomyini, 2n = 54), Necromys lasiurus—NLA (Akodontini, 2n = 34) and Akodon sp.–ASP (Akodontini, 2n = 10) have extreme diploid numbers that make it difficult to understand the rearrangements that are responsible for such differences. In this study we analyzed these changes using whole chromosome probes of HME in cross-species painting of NLA and ASP to construct chromosome homology maps that reveal the rearrangements between species. We include data from the literature for other Sigmodontinae previously studied with probes from HME and Mus musculus (MMU) probes. We also use the HME probes on MMU chromosomes for the comparative analysis of NLA with other species already mapped by MMU probes. Our results show that NLA and ASP have highly rearranged karyotypes when compared to HME. Eleven HME syntenic blocks are shared among the species studied here. Four syntenies may be ancestral to Akodontini (HME2/18, 3/25, 18/25 and 4/11/16) and eight to Sigmodontinae (HME26, 1/12, 6/21, 7/9, 5/17, 11/16, 20/13 and 19/14/19). Using MMU data we identified six associations shared among rodents from seven subfamilies, where MMU3/18 and MMU8/13 are phylogenetic signatures of Sigmodontinae. We suggest that the associations MMU2entire, MMU6proximal/12entire, MMU3/18, MMU8/13, MMU1/17, MMU10/17, MMU12/17, MMU5/16, MMU5/6 and MMU7/19 are part of the ancestral Sigmodontinae genome. PMID:26800516

  13. Dieta de roedores sigmodontinos (Cricetidae en los bosques montanos tropicales de Huánuco, Perú

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    Maggie C. Noblecilla

    2013-06-01

    Full Text Available Se analizó el contenido estomacal de cinco especies de roedores sigmodontinos: Akodon orophilus, Microry-zomys altissimus, M. minutus, Thomasomys notatus yT. kalinowskii, procedentes de los bosques montanos de Huánuco, Perú (2564 - 3850 m de altitud. Concluimos que A. orophiluses insectívora por haber presentado un alto volumen de artrópodos (adultos y larvas en el contenido estomacal (90,1%; mientras que T. notatusy T. kalinowskiison principalmente herbívoras por el alto volumen de materia vegetal, 89% y 67,75% respectiva-mente; y que M. altissimusy M. minutusson omnívoras por presentar volúmenes similares tanto para vegetales como para artrópodos. Thomasomys kalinowskiies considerada generalista por la mayor amplitud de nicho (4,61, mientras A. orophiluses considerada especialista por el menor valor (1,70. Akodon orophilusmostró una preferencia por el consumo de artrópodos adultos al tener un bajo coeficiente de variación (CV= 20% y también un significativo aumento en el consumo de larvas de artrópodos en la época húmeda, siendo la única especie con variación estacional en la dieta. Por otro lado, la sobreposición de nicho fue menor a 0,75 en el 80% de los pares de especies comparados, indicando una baja similitud en la dieta. La mayor similitud en la dieta se observó entre M. altissimus- T. notatus(0,822 y M. minutus - T. kalinowskii(0,816. Se concluye que estos roedores sigmodontinos, simpátricos en los bosques montanos de Huánuco, exhiben dietas disímiles, probablemente como una estrategia para evitar o aminorar la competencia interespecífica.

  14. Parasite diversity at the Holarctic nexus: species of Arostrilepis (Eucestoda: Hymenolepididae) in voles and lemmings (Cricetidae: Arvicolinae) from greater Beringia.

    Science.gov (United States)

    Makarikov, Arseny A; Galbreath, Kurt E; Hoberg, Eric P

    2013-01-23

    Previously unrecognized species of hymenolepidid cestodes attributable to Arostrilepis Mas-Coma & Tenora, 1997 in arvicoline rodents from the greater Beringian region and western North America are described. Discovery and characterization of these tapeworms contributes to the recognition of a complex of cryptic species distributed across the Holarctic region. Three species are proposed: Arostrilepis gulyaevi sp. n. is named for cestodes in Myodes rufocanus from the Republic of Buryatia, southeastern Siberia and from the Khabarovskiy Kray, Chukotka Autonomous Okrug, and Magadanskaya Oblast', Russian Far East (western Beringia); A. cooki sp. n. is named for cestodes in Myodes gapperi from British Columbia, Canada and Montana, USA; and A. rauschorum sp. n. is named for cestodes in Microtus oeconomus, M. longicaudus, M. pennsylvanicus and M. xanthognathus from the Brooks Range, Seward Peninsula, north-central interior, and Arctic coastal plains of Alaska (eastern Beringia) and Montana, USA. Consistent with recent studies defining diversity in the genus, the form, size, and spination (pattern, shape and size) of the cirrus are diagnostic; species are further distinguished by the relative position and length of the cirrus sac, and arrangement of the testes. Assessment of genetic data from the cytochrome b gene of mitochondrial DNA complements differentiation of this complex based on morphological attributes and confirms known species diversity within the genus. New data for geographical distribution and host specificity of known Arostrilepis spp. indicate that 3 of 12 recognized species have Holarctic distributions extending across Beringia. These include Arostrilepis beringiensis (Kontrimavichus & Smirnova, 1991) in lemmings (species of Lemmus and Synaptomys), A. cf. janickii Makarikov & Kontrimavichus, 2011 in root voles (M. oeconomus) MAKARIKOV ET AL. 402 · Zootaxa 3608 (6) © 2013 Magnolia Press and A. macrocirrosa Makarikov, Gulyaev & Kontrimavichus, 2011 in red backed voles (species of Myodes) and less often other rodent host species.

  15. Diversity at the Holarctic nexus: species of Arostrilepis (Eucestoda: Hymenolepididae) in arvicoline rodents (Cricetidae: Arvicolinae) from greater Beringia

    Science.gov (United States)

    Previously unrecognized species of hymenolepidid cestodes attributable to Arostrilepis Mas-Coma & Tenora, 1997 in arvicoline rodents from the greater Beringian region and western North America are described. Discovery and characterization of these tapeworms contributes to the recognition of a compl...

  16. Evolution of spatially coexpressed families of type-2 vomeronasal receptors in rodents.

    Science.gov (United States)

    Francia, Simona; Silvotti, Lucia; Ghirardi, Filippo; Catzeflis, François; Percudani, Riccardo; Tirindelli, Roberto

    2014-12-23

    The vomeronasal organ (VNO) is an olfactory structure for the detection of pheromones. VNO neurons express three groups of unrelated G-protein-coupled receptors. Type-2 vomeronasal receptors (V2Rs) are specifically localized in the basal neurons of the VNO and are believed to sense protein pheromones eliciting specific reproductive behaviors. In murine species, V2Rs are organized into four families. Family-ABD V2Rs are expressed monogenically and coexpress with family-C V2Rs of either subfamily C1 (V2RC1) or subfamily C2 (V2RC2), according to a coordinate temporal diagram. Neurons expressing the phylogenetically ancient V2RC1 coexpress family-BD V2Rs or a specific group of subfamily-A V2Rs (V2RA8-10), whereas a second neuronal subset (V2RC2-positive) coexpresses a recently expanded group of five subfamily-A V2Rs (V2RA1-5) along with vomeronasal-specific Major Histocompatibility Complex molecules (H2-Mv). Through database mining and Sanger sequencing, we have analyzed the onset, diversification, and expansion of the V2R-families throughout the phylogeny of Rodentia. Our results suggest that the separation of V2RC1 and V2RC2 occurred in a Cricetidae ancestor in coincidence with the evolution of the H2-Mv genes; this phylogenetic event did not correspond with the origin of the coexpressing V2RA1-5 genes, which dates back to an ancestral myomorphan lineage. Interestingly, the evolution of receptors within the V2RA1-5 group may be implicated in the origin and diversification of some of the V2R putative cognate ligands, the exocrine secreting peptides. The establishment of V2RC2, which probably reflects the complex expansion and diversification of family-A V2Rs, generated receptors that have probably acquired a more subtle functional specificity.

  17. Robertsonian chromosome polymorphism of Akodon molinae (Rodentia: Sigmodontinae: analysis of trivalents in meiotic prophase Polimorfismo cromosómico Robertsoniano de Akodon molinae (Rodentia: Sigmodontinae

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    RAÚL FERNÁNDEZ-DONOSO

    2001-03-01

    Full Text Available Akodon molinae (with 2n = 42-43-44 and an FN = 44 shows a remarkable polymorphism of chromosome 1 in natural and laboratory populations. Specimens 2n = 42, named single homozygotes (SH, have a chromosome pair 1 formed by two large metacentric chromosomes. Specimens 2n = 3, heterozygotes (Ht, have one chromosome 1 and two medium-sized subtelocentric chromosomes, 1a and 1b, which are homologous with the long and short arms of chromosome 1 respectively. Specimens 2n = 44 are double homozygotes (DH, with just two pairs of medium-sized subtelocentric chromosomes, 1a and 1b. Analysis of meiotic metaphases I and II showed that anomalous segregation occurs more frequently in spermatocytes carrying the 1a and 1b chromosomes. This would disturb gametogenesis and other reproductive and developmental processes, producing a marked decrease in viability of DH individuals. There is, as yet, no satisfactory explanation for these phenomena. To investigate structural elements which might explain such segregational anomalies, we have studied bivalent and trivalent synapsis in pachytene spermatocytes from SH, Ht and DH specimens. Of a total of 80 spermatocyte nuclei microspreads, the following results were obtained: of 16 microspreads from two SH individuals, 20 autosomic bivalents plus the XY bivalent were observed; of 48 microspreads from three Ht individuals, 19 autosomic bivalents, 1 trivalent and an XY bivalent were seen; and of the 16 microspreads from two DH individuals, 21 autosomic bivalents plus the XY bivalent were found. Trivalents analysed showed complete pairing between the short arms of 1a and 1b, and having an apparently normal synaptonemal complex (SC with lengths of 1 and 2.8 µm. The trivalent SC showed three telomeric ends, corresponding to arms: q1 and q1a; p1 and q1b; and p1a and p1b, with attachment plates to the nuclear envelope of normal organisation. None of the trivalents showed asynapsis or desynapsis between p1a and p1b, nor an association with the XY bivalent. In 70 % of spermatocytes studied, the XY bivalent showed complete pairing between X and Y, with SC formation along the whole length of the Y chromosome. The remaining 30 % showed partial pairing, with an SC length which varied from the common end. Based on these findings and those of previous studies, we discuss: 1.- that the obliged configuration of the trivalent, with SC formation between the short arms of 1a and 1b, helps to assure a quasi normal segregation between 1, 1a and 1b in anaphase I of Ht meiosis; and 2.- that co-existence in trivalents of chromosomes 1, 1a and 1b in Ht individuals, breaks down the structural and functional integrity of the short arms of 1a and 1b, producing an accumulative damage which would also explain the decreased viability of individuals bearing these chromosomesAkodon molinae con 2n = 42-43-44 y FN = 44 presenta un notable polimorfismo en el cromosoma 1 en poblaciones naturales y de laboratorio, los individuos 2n = 42 tienen un par 1 formado por dos cromosomas metacéntricos grandes y son denominados homocigotos simples (SH; los individuos 2n = 43, heterocigotos (Ht, presentan un cromosoma 1 y dos cromosomas subtelocéntricos de tamaño medio 1a and 1b, que son homólogos con los brazos largo y corto del 1, respectivamente; y los individuos 2n = 44 que son los doble homocigotos (DH y presentan dos pares de cromosomas subtelocéntricos 1a y 1b. Análisis de la metafases I y II meióticas han demostrado que se producen segregaciones anómalas con una alta frecuencia en los espermatocitos portadores de los cromosomas 1a and 1b. Ello alteraría a otros procesos, como la gametogénesis, la reproducción y el desarrollo, disminuyendo la viabilidad individual y poblacional de los DH. No ha habido una explicación satisfactoria para estos fenómenos. Para investigar elementos estructurales que pudiesen explicar tales alteraciones segregacionales, se estudió la sinapsis de bivalentes y trivalentes en espermatocitos en paquiteno de ejemplares SH, Ht y DH. De un total de 80 microesparcidos de núcleos de espermatocitos: en 16 núcleos de ejemplares SH se observaron 20 bivalentes autosómicos más el bivalente XY; en 48 núcleos de Ht se observaron 19 bivalentes autosómicos, 1 trivalente y un bivalente XY; y en 16 núcleos de DH se observaron 21 bivalentes autosómicos más el bivalente XY. Los trivalentes analizados mostraron apareamiento completo entre los brazos cortos de 1a y 1b conformándose un complejo sinaptonémico (CS aparentemente normal con una longitud entre 1 µm y 2,8 µm. El CS de los trivalentes presentó tres extremos teloméricos correspondientes a los brazos: q1 y q1a, p1 y q1b y p1a y p1b, con placas de inserción a la envoltura nuclear de organización normal. En ninguno de los trivalentes se observó asinapsis o desinapsis entre p1a y p1b, ni asociaciones con el bivalente XY. En el 70 % de los espermatocitos estudiados el bivalente XY mostró apareamiento completo entre X e Y, con formación de CS en toda la longitud del cromosoma Y. El 30 % restante presentó apareamiento parcial con un CS de longitud variable a partir del extremo común. Sobre la base de los resultados de este trabajo y los antecedentes existentes, se discute: 1.- que la configuración obligada del trivalente con formación de CS entre los brazos cortos de 1a y 1b, contribuye a asegurar la segregación cuasi normal entre 1, 1a y 1b en la I anafase de la meiosis de los Ht; y 2.- que la coexistencia en los trivalentes de los cromosomas 1, 1a y 1b en los Ht, erosiona la integridad estructural y funcional de los brazos cortos de 1a y 1b, daño que sería acumulativo y que explicaría la viabilidad disminuída de los individuos portadores de estos cromosomas

  18. Comportamentos e atividade diária de Sciurus ingrami (Thomas em cativeiro (Rodentia, Sciuridae Behaviour and diary activity of Sciurus ingrami (Thomas in captivity (Rodentia, Sciuridae

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    Marcelo Bordignon

    1997-09-01

    Full Text Available From October 1994 to November 1995 the behaviour, postures and diurnal activity of tive captive squirrels Sciurus ingrami were observed and registered. Four basics postures, five grooming behaviours, displacements and face wiping behaviour were identified. Based on behavioural observations, the diurnal activity was divided into four categories: resting, displacement, teeding and maintenance. The time spent in each category varied seasonally and the squirrels spent more time resting during winter and spring. However, more time was spent feeding during autum and summer and was reduced the displacement in autum. Two types of breeding behaviour were identified: sexual trailing and mating chase of females by males. However copulatori behaviour was not recorded during the studied period. We also verified that S. ingrami presents thermorregulation behaviour during winter, remaining resting in the nest to conserve energy in heath maintenance. During the hottest seasons, the squirrels remain resting out of the nest, placed on the branchs to decrease their body heat to normal temperature, The behaviours observed in this study were similar to those described in the literature, as well as the mating behaviour, which was very similar to S. carolinensis.

  19. VARIACIÓN CARIOLÓGICA EN DIFERENTES FENOTIPOS DE Sciurus granatensis (RODENTIA, SCIURIDAE Karyologic Variation in Different Phenotypes of Sciurus granatensis (Rodentia, Sciuridae

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    CAROLINA ARANGO

    Full Text Available Siete ejemplares de Sciurus granatensis (ardilla colombiana de diferentes fenotipos según color, rescatadas del tráfico ilegal de fauna silvestre de Colombia fueron estudiadas. Mediante técnicas convencionales de bandeo cromosómico G, C, Q, R y NOR se estableció su cariotipo 2n=42. Se encontraron tres cariomorfos de acuerdo al Número Fundamental (NF y características propias de cada uno de los complementos ocasionadas por distintos rearreglos cromosómicos, lo cual sugiere que S. granatensis es un complejo de especies. No se observó relación entre cariotipo y fenotipo. La variación en el color del pelaje se debe probablemente a las condiciones ambientales.Seven specimens of Sciurus granatensis (redtailed squirrel rescued from illegal fauna traffic in Colombia were studied; they had different phenotypes according to colour. G, C, Q, R and NOR chromosome banding was used, being found a 2n=42 diploid number for the Sciurus granatensis Colombian squirrels. There were 3 karyomorphs according to fundamental number (FN and different chromosomal characteristics caused by rearregement, suggesting that S. granatensis represents a complex of species. Relationships between karyotype and phenotype were not observed. The variation in the colour of sqirrels’ fur was probably due to environmental conditions.

  20. Variación cariológica en diferentes fenotipos de Sciurus granatensis (Rodentia, Sciuridae Karyologic Variation in Different Phenotypes of Sciurus granatensis (Rodentia, Sciuridae

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    Chacón Marcos Nicolás

    2007-12-01

    Full Text Available Siete ejemplares de Sciurus granatensis (ardilla colombiana de diferentes fenotipos según color, rescatadas del tráfico ilegal de fauna silvestre de Colombia fueron estudiadas. Mediante técnicas convencionales de bandeo cromosómico G, C, Q, R y NOR se estableció su cariotipo 2n=42. Se encontraron tres cariomorfos de acuerdo al Número Fundamental (NF y características propias de cada uno de los complementos ocasionadas por distintos rearreglos cromosómicos, lo cual sugiere que S. granatensis es un complejo de especies. No se observó relación entre cariotipo y fenotipo. La variación en el color del pelaje se debe probablemente a las condiciones ambientales.Seven specimens of Sciurus granatensis (redtailed squirrel rescued from illegal fauna traffic in Colombia were studied; they had different phenotypes according to colour. G, C, Q, R and NOR chromosome banding was used, being found a 2n=42 diploid number for the Sciurus granatensis Colombian squirrels. There were 3 karyomorphs according to fundamental number (FN and different chromosomal characteristics caused by rearregement, suggesting that S. granatensis represents a complex of species. Relationships between karyotype and phenotype were not observed. The variation in the colour of sqirrels' fur was probably due to environmental conditions.

  1. Registro nuevo de Neotoma mexicana vulcani (Rodentia: Muridae para México A new record of Neotoma mexicana vulcani (Rodentia: Muridae in Mexico

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    Roberto Vidal-López

    2005-12-01

    Full Text Available Se registra la presencia de Neotoma mexicana vulcani en México, subespecie antes considerada como endémica del volcán Tajomulco, Departamento de San Marcos, Guatemala. La identificación se llevó a cabo con base en la revisión de las medidas morfométricas y patrones de coloración de ejemplares recientemente recolectados y registros de bases de datos. Con estos resultados, el área de distribución de la subespecie se amplía hacia México en la Sierra Madre de Chiapas, aproximadamente a 50 km al norte de la localidad anteriormente conocida.We report the presence of Neotoma mexicana vulcani in Mexico; this subspecies has been considered endemic to the Tajomulco volcano, in the Departamento of San Marcos, Guatemala. We identified our specimens using measurements, color patterns of recently colleted specimens, and data base records. Based on our results, the distribution range of this subspecies extends to Mexico, in the Sierra Madre of Chiapas, approximately 50 km north of the previously known locality.

  2. Obsessed with grasses?: The case of mara Dolichotis patagonum(Caviidae: Rodentia ¿Obsesionada con gramíneas?: El caso de mara Dolichotis patagonum (Caviidae: Rodentia

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    MOIRA S. SOMBRA

    2005-09-01

    Full Text Available The diet of mara (Dolichotis patagonum, Zimmeraman 1780 within the limits of Sierra de las Quijadas National Park (San Luis, Argentina is described. Other studies regarding mara’s diet showed that mara, feeds on different species of grasses and shrubs. However, there is controversy regarding the proportions of these items in the diet or whether this proportion varies seasonally. Considering mara’s body size, anatomical features and physiology, we suggest that mara feeds on grasses in a greater proportion than shrubs and forbs. Moreover, giving that in this region precipitation varies considerably between seasons; it is also expected to find a correlation between the diet of mara and seasons. Fecal pellets of mara were collected during four periods including two dry, and two wet seasons. Relative frequency of each item in scats was determined by microhistological analysis. Results support the hypothesis that mara shows preference for grasses, despite they are less available than shrubs and forbs and that this preference remains constant through seasons regardless of the precipitation regime. The characteristics of mara’s diet and the ecological implications of these findings are discussedEn este trabajo se describe la dieta de mara (Dolichotis patagonum Zimmeraman 1780 en el Parque Nacional Sierra de las Quijadas (San Luis, Argentina. Los estudios realizados sobre su dieta indican que se alimenta de varias especies de gramíneas y arbustos. Sin embargo, existe cierta controversia acerca de la proporción en que se presentan estos ítemes, y si las mismas varían estacionalmente. En base al tamaño corporal de mara, y a sus características anatómicas y fisiológicas se propone que, mara consume una mayor proporción de gramíneas que de otras hierbas no graminiformes y dicotiledóneas en general. Además esperamos una variación estacional de la dieta, correlacionada a una posible variación estacional en los recursos alimentarios asociada a las precipitaciones. Se colectaron muestras de heces correspondientes a cuatro estaciones en el parque, dos estaciones secas y dos lluviosas. Mediante análisis microhistológico se determinó la proporción de cada ítem medido como frecuencia de aparición en las heces. Los resultados apoyan la hipótesis de un consumo preferencial de gramíneas por parte de mara. Las gramíneas aparecen en mayor proporción en la dieta a pesar de estar en menor disponibilidad en el hábitat y sin que el régimen de precipitación tenga algún efecto Se discuten las características de la dieta de mara y las implicancias ecológicas relacionadas con esta especie

  3. Metabolic rates and thermoregulatory characteristics of Akodon azarae (Rodentia: Sigmodontinae Tasas metabólicas y características termorregulatorias de Akodon azarae (Rodentia: Sigmodontinae

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    C. DANIEL ANTINUCHI

    2000-03-01

    Full Text Available In this work, we evaluated the energetic status, activity daily metabolic rate, thermoregulatory capacity and the existence of torpor in Akodon azarae (Fisher 1829. Basal metabolic rate (BMR was similar to the expected value from Kleiber´s, and also according to the BMR of phylogenetically related species. No statistical difference in BMR between sexes was detected. For both males and females, activity daily metabolic rate was 235 % of BMR. Body temperature was not statistically different, neither at different ambient temperatures nor between sexes. In the thermoneutral zone, body temperature was 36.1 ± 1.5 °C. Thermal conductance was lower than the expected for mammals whereas thermoregulatory capacity was 136 % of the expected. Akodon azarae did not show evidence of torporEn este trabajo fueron evaluadas, para Akodon azarae (Fisher 1829, la tasa metabólica basal (BMR y de actividad diaria así como la capacidad termorregulatoria y la posible existencia de torpor. La BMR no presentó diferencias estadísticas con la esperada por la ecuación de Kleiber así como con la esperada para especies filogenéticamente relacionadas. Tampoco fueron detectadas diferencias significativas en la BMR entre sexos. La tasa metabólica de actividad diaria para ambos sexos fue el 235 % de la BMR. La temperatura corporal no presentó variaciones entre individuos mantenidos a diferentes temperaturas ambiente ni tampoco entre sexos y en termoneutralidad fue de 36,1 ± 1,5 °C. Por otra parte, la conductancia térmica fue menor a la esperada mientras que la capacidad termorregulatoria fue el 136% de la esperada. Akodon azarae no presenta sopor

  4. 21 CFR 520.1194 - Ivermectin meal.

    Science.gov (United States)

    2010-04-01

    .... For treatment and control of Large Strongyles (adults): Strongylus vulgaris (also early forms in blood vessels), S. edentatus (also tissue stages), S. equinus, Triodontophorus spp. including T. brevicauda...

  5. Molecular phylogenetic position of endangered Wilfredomys within Sigmodontinae (Cricetidae) based on mitochondrial and nuclear DNA sequences and comments on Wiedomyini.

    Science.gov (United States)

    Machado, Leonardo Ferreira; Passaia, Milena Henrique; Rodrigues, Fernando Pacheco; Peters, Felipe Bortolotto; Sponchiado, Jonas; Valiati, Victor Hugo; Christoff, Alexandre Uarth

    2015-07-20

    Wilfredomys, a monotypic genus of endangered sigmodontine rats, was historically related to the tribe Thomasomyini or considered "incertae sedis". Given no molecular data is available for Wilfredomys, the phylogenetic position of this taxon is uncertain in relation to modern, molecular hypotheses of sigmodontine relationships. We investigate the phylogeny of Wilfredomys to provide a hypothesis of its position within Sigmodontinae based on nuclear and mitochondrial DNA sequences. Bayesian and maximum likelihood phylogenetic analyses recovered Wilfredomys oenax as sister to Wiedomys pyrrhorhinos, and Wie. cerradensis fell out sister to this clade. At the genus level, Phaenomys is sister to Wilfredomys + Wiedomys, forming a novel and well-supported sigmodontine clade. Our results suggest that tribe Wiedomyini should encompass Wilfredomys in addition to Wiedomys and Cholomys, thus the hypothesis that Wiedomys is paraphyletic should be investigated further. Another plausible classification scheme consistent with our results would be to expand Wiedomyini to encompass the clade composed of Phaenomys + Wilfredomys + Wiedomys. Last, our recovery of an "Atlantic clade" composed of lineages restricted to eastern South America supports the idea that this region has likely played an important role in sigmodontine diversification.

  6. Records of Coendou ichillus (Rodentia, Erethizontidae) from the Lower Urubamba Region of Peru

    Science.gov (United States)

    Gregory, Tremaine; Lunde, Darrin; Zamora-Meza, Hugo Tomás; Carrasco-Rueda, Farah

    2015-01-01

    Abstract Coendou ichillus was first described in 2001 by Voss and da Silva, with a range from Amazonian Ecuador to Iquitos, Peru. Here, we describe an adult female Coendou ichillus specimen collected in a Tomahawk trap in the forest canopy of the Lower Urubamba Region of Peru in October 2013. We also describe pathologies and behaviors observed through 379 camera trapping photo events (2,196 photos) gathered in natural canopy bridges over the course of a year (7,198 trap nights), including information on activity period over the course of the day and over the course of the lunar cycle. We conservatively estimate that 17 individuals were photographed, including one juvenile. Being 900 km away from Iquitos, Peru (the site of the closest record), discovery of this species in the Lower Urubamba constitutes a significant range extension. PMID:26175605

  7. Dinomys branickii Peters, 1873 (Rodentia, Dinomyidae: consumption and food preference in captivity

    Directory of Open Access Journals (Sweden)

    Raymundo Tomaz Melo dos Santos Neto

    2017-02-01

    Full Text Available Dinomys branickii is a large rodent listed as Endangered (EN, that suffers pressure from anthropogenic activities such as hunting and habitat destruction. Captive breeding methods are viable for supplementation of conservation projects, and may enhance our knowledge of main aspects of the biology of this species. The objective of this study was to determine consumption and food preferences in a captive group of D. branickii. To determine feeding preferences, the Food Preference Index (P was used for the type of food with highest consumption. The mean amount of food provided was 6.6 kg per day per group, with 4.4 kg per day/group consumed (66%. An average of 11 ± 2.9 types of food were offered daily. The consumption of fruits (71% was higher than the consumption of other food groups, followed by roots/tubers (65.3%. The food groups least consumed were cereals and seeds (39.4% and leaves (38.3%. The preferred foods were: Brassica oleracea (P = 1.38, Zea mays (P = 1.25, Ipomoea batatas (P = 1.17, Mangifera indica (P = 1.13, Cucurbita moschata (P = 1.10, Talinum esculentum (P = 1.00 and Manihot esculenta (P = 1.00. These results suggest that foods with high fiber and carbohydrate content are the best choices for D. branickii development and well-being in captivity.

  8. Age Variations in Microtus guentheri Danford and Alston, 1880 (Mammalia: Rodentia) in Turkey

    OpenAIRE

    SÖZEN, Mustafa; ÇOLAK, Ercüment; Nuri YİĞİT

    1999-01-01

    The skull, teeth, phallus and bacula of Microtus guentheri specimens raised in the laboratory were investigated at different stages of postnatal development. The most of the cranial measurements attained those of adults on day 60. There were determined to be some morphological differences between the skulls of young and adult voles. The incisors and the molars began to erupt at 3 and 6 days, respectively. It was shown that there was no difference in respect to the phallic and bacular morpholo...

  9. Studies on Rift Valley fever in some African murids (Rodentia: Muridae).

    Science.gov (United States)

    Swanepoel, R; Blackburn, N K; Efstratiou, S; Condy, J B

    1978-04-01

    Brains, spleens and livers of 2214 murids, 27 shrews and 7 dormice, trapped at 7 sites in Rhodesia, were tested in 277 pools for the presence of Rift Valley Fever virus. There were no isolations of Rift Valley Fever, but 69 isolations of an unidentified virus were obtained. Sixteen out of 867 sera had low-titre haemagglutination-inhibition activity against Rift Valley Fever antigen, but only one out of 1260 sera had neutralizing antibody. The evidence suggests that murids fail to encounter infection in nature and are unlikely to play a role in circulation and dissemination of Rift Valley Fever virus. Four out of seven widely distributed species of muried, Rhabdomys pumilio, Saccostomys campestris, Aethomys chrysophilus and Lemniscomys griselda, were shown to be capable of circulating amounts of virus likely to be infective for mosquitoes.

  10. Chromosomal and molecular characterization of Aethomys kaiseri from Zambia and Aethomys chrysophilus from Tanzania (Rodentia, Muridae).

    Science.gov (United States)

    Castiglia, Riccardo; Corti, Marco; Colangelo, Paolo; Annesi, Flavia; Capanna, Ernesto; Verheyen, Walter; Sichilima, Alfred Matafwali; Makundi, Rhodes

    2003-01-01

    Aethomys is a common and widespread rodent genus in the African savannas and grasslands. However, its systematics and taxonomy are still unclear as no study has covered the entire range. In fact it might not be a monophyletic genus and perhaps should be split into two subgenera, Micaelamys and Aethomys. In this paper, we present findings based on the cytogenetics and the entire cytochrome b sequence of two species from Zambia (A. kaiseri) and Tanzania (A. chrysophilus), and we compare them with the sequences of a South African species (A. namaquensis) and other allied muroid genera. Comparison of the banded chromosomes revealed complete G-band homology between the autosomes of the two species. However, the X and Y chromosomes clearly differ in size and in C- and G-banding, being much larger in A. kaiseri. Comparison of the cytochrome b sequences places the separation between A. kaiseri and A. chrysophilus at 4.49 Mya, a period of intense speciation in other African muroids. The resulting phylogeny strongly supports the idea of a paraphyletic group, suggesting the need to elevate the previously described subgenera to the genus rank.

  11. New record on Pigmy Field Mouse (muridae, rodentia from northeast Iran

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    Jamshid Darvish

    2011-02-01

    Full Text Available

    Abstract
    In this study the field mice of eastern Elborz in Golestan province were examined using molecular, morphologic and morphometric characters. RFLP analysis indicates the presence of three different haplotypes called as A, B and C. Taxonomic determination of the specimens of the haplotyes shows that haplotypes A, B and C represents three different species, A. cf. uralensis, A. cf. hyrcanicus and A. witherbeyi, respectively. Two latter species were previously reported from the studied area. However, the discovery of A. cf. uralensis in this region extends the eastern border of the distribution of this species up to eastern Elbruz and confirms the sympatric occurrence of A. uralensis and A. hyrcanicus in the Golestan province. 

  12. A new form of rodent placentation in the relict species, Laonastes aenigmamus (Rodentia Diatomyidae)

    DEFF Research Database (Denmark)

    Carter, Anthony Michael; Enders, A C; Jones, C J P

    2013-01-01

    . METHODS: We examined the reproductive tract of nonpregnant (n = 5), early (n = 3) and mid to late gestation (n = 2) females. Selected characters were mapped to a phylogenetic tree to examine their evolution in rodents. RESULTS: The chorionic placenta was discoid and labyrinthine with a spongy zone...... but without internal lobes. The interhemal region was hemodichorial with syncytiotrophoblast lining maternal blood spaces and an inner layer of vacuolated cytotrophoblast. There was no subplacenta. The yolk sac was well developed with a villous portion that faced the placental disk but no fibrovascular ring....... There was a single fetus that very likely would be precocial at birth. DISCUSSION: A lobulated labyrinth and the presence of a subplacenta and a fibrovascular ring emerged as synapomorphies for Hystricognathi. Laonastes, Ctenodactylus and stem Hystricognathi all had precocial young, whereas altriciality...

  13. Effects of classical music as part of environmental enrichment in captive Mus musculus (Rodentia: Muridae

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    José Geraldo Pereira da Cruz

    2010-06-01

    Full Text Available In the wild, animals are exposed to an ever-changing array of sensory stimuli. The captive environment, by contrast, is generally much more impoverished in terms of the cues it offers the animals housed within. In a bid to remedy this, and promote better welfare, mice (Mus musculus were exposed to two conditions: no auditory stimulation, and stimulation with classical music. In all experiments, a battery of behavior tests was used. The results demonstrated significantly decreased immobility in the forced swim, increased enclosed arm entries in the plus-maze, and decreased immobility in the open-field, in animals that had been pre-exposed to music 24h earlier, suggesting that changes in mouse motor activity were caused by classical music. This study led to the conclusion that environmental enrichment may have profound effects on the behavior of mice in behavioral tests, and that classical music can be a relatively simple method of contributing to the well-being of captive mice, but it can affect the results of experiments such as forced swimming.

  14. A new karyotype of Wiedomys pyrrhorhinus (Rodentia: Sigmodontinae from Chapada Diamantina, northeastern Brazil

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    Ana L. G Souza

    2011-02-01

    Full Text Available A new karyotype of Wiedomys pyrrhorhinus (Wied, 1821 is described, including G- and C-banding and Ag-NOR sites from specimens collected in the municipality of Morro do Chapéu, situated in the northern region of the Chapada Diamantina, state of Bahia. Karyological studies of W. pyrrhorhinus have shown a constant diploid number (2n of 62 with two different numbers of autosomal arms (FNa: 86 and 90, respectively. The new karyotype revealed 2n = 62 and FNa = 104, being the higher autosomal number found so far for this genus. The X chromosome is a large acrocentric and the Y chromosome is a small acrocentric. The analysis of the karyotype morphology suggests that this new karyotype is more closely related to the previous karyotype with 2n = 62 and FNa = 90, described from Caetité, Bahia State. Further studies, comparing different populations of W. pyrrhorhinus, including molecular approaches, may help to better understand the geographical limits of each population and their phylogenetic relationships in the Caatinga biome

  15. Revision of bank vole Clethrionomys glareolus (Schreber, 1780 (Mammalia, Rodentia distribution in Serbia and Montenegro

    Directory of Open Access Journals (Sweden)

    Paunović M.

    2005-01-01

    Full Text Available The present article represents a complete review of all published data (with corrections on bank vole Clethrionomys glareolus distribution in Serbia and Montenegro. On the other hand, data of 63 unpublished records stored in the period from 1956 to 1983 in the Mammal Study Collection of the Natural History Museum, Belgrade had not been processed until now. In the period from 1992 to 2004, 29 new findings were recorded, 12 of them outside the currently known area of distribution. New data reveal a wider distribution of bank vole than was known until now, completing and partly modifying previous knowledge about this rodent's bionomy and ecology in Serbia and Montenegro. The occurrence of bank vole in the Prokletije Mountains, Kosovo and Metohija represents its highest known altitude in Europe (2500 m. On the basis of these new data and observations, we can conclude that bank vole is continuously present in small and linear fragments of autochthonous woodlands on plains and hills, and that there are no large discontinuities in its distribution in Serbia and Montenegro, as was assumed earlier. In efforts to preserve overall biological diversity, the example of the bank vole underlines the need to intensify protection and management of woodlands especially remaining fragments of forests on plains and in hills.

  16. Variación cariológica en diferentes fenotipos de Sciurus granatensis (Rodentia, Sciuridae

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    Bueno Angulo Marta Lucía

    2007-04-01

    Full Text Available Debido a la poca información ecológica, taxonómica o genética sobre las ardillas colombianas, existen problemas
    sistemáticos aun no resueltos (Emmons LH, 1990, lo cual dificulta la reubicación y/o liberación de ejemplares sin procedencia, provenientes del tráfico ilegal de fauna silvestre. Estudios cariológicos sirven para detectar variaciones intra e interespecíficas por lo que en este trabajo se busco detectar diferencias cariotípicas entre varios fenotipos Sciurus granatensis. La diferenciación genética en conservación, puede ser una herramienta
    útil en la toma de decisiones en los procesos de liberación de ejemplares capturados, dado que la introducción
    de individuos con genomas diferentes en un población puede originar un proceso de depresión por exogamia o introgresión genética (pérdida de alelos adaptativos locales, procesos nocivos para la población receptora. Se estudiaron siete especímenes (cinco hembras y dos machos de S. granatensis procedentes del tráfico ilegal. Los cariotipos fueron obtenidos a partir de cultivos de linfocitos de sangre periférica. Las metafases con bandas G, R, C, Q y NOR, se analizaron al microscopio y se ordenaron en el programa Lucia Karyotyping®. Los individuos estudiados corresponden a los tres fenotipos reportados por Emmons LH, 1990, pero con una gran variación cariológica. Solo uno de los machos no corresponde a los fenotipos descritos, y además presenta varios rearreglos cromosómicos que lo diferencian notablemente de los demás, por lo cual posiblemente se trate de un híbrido estéril originado de dos poblaciones diferenciadas cariológicamente. El número de cromosomas fue constante (2n=42, con variación en el número fundamental (NF=80; 81, por lo cual se reportan tres cariomorfos para Sciurus granatensis, según NF y los rearreglos cromosómicos encontrados. Se observó variación en los pares 9, 16 y una translocación universal entre autosomas dentro de uno de los ejemplares. El cromosoma X es submetacéntrico mediano. El cromosoma Y es acrocéntrico, coincidente con lo descrito para Sciurus. No se registró una relación cariotipo-fenotipo. Por lo tanto se puede sugerir que Sciurus granatensis, es un complejo de especies con diferencias cariológicas y morfológicas que no ha sido estudiado a profundidad teniendo en cuenta su amplia distribución geográfica.

  17. Fatal placental subinvolution in a captive capybara (Hydrochaeris hydrochaeris, Order Rodentia).

    Science.gov (United States)

    Juan-Sallés, C; Martínez, L S; Garner, M M

    2005-07-01

    An adult, captive-born female capybara died of systemic thrombosis and hemoperitoneum associated with placental subinvolution. Grossly, the uterus was enlarged, segmentally thickened, and associated with a large blood clot in the abdominal cavity. There was hemometra and a large ovoid mass in each uterine horn weakly adhered to the endometrium, and the right uterine horn wall had a small perforation over the mass. The mesometrial veins were markedly dilated due to thrombosis and occasionally perforated. Histologically, the uterine masses consisted of partly necrotic placental and subplacental tissue. The uterine wall surrounding the masses had full-thickness coagulative necrosis of the myometrium and diffuse endometrial ulceration with abundant syncytiotrophoblast-like cells within capillaries. Vascular lesions in the uterus and mesometrium consisted of mural invasion by cytotrophoblast and syncytiotrophoblast-like cells, thrombosis, fibrinoid necrosis, and/or heterophilic vasculitis. This is the first report of placental subinvolution in capybaras or any rodent species, to the authors' knowledge.

  18. Seasonal changes in burrow geometry of the common mole rat (Rodentia: Bathyergidae)

    Science.gov (United States)

    Thomas, H. G.; Scantlebury, M.; Swanepoel, D.; Bateman, P. W.; Bennett, N. C.

    2013-11-01

    Sociality in mole rats has been suggested to have evolved as a response to the widely dispersed food resources and the limited burrowing opportunities that result from sporadic rainfall events. In the most arid regions, individual foraging efficiency is reduced, and energetic constraints increase. In this study, we investigate seasonal differences in burrow architecture of the social Cryptomys hottentotus hottentotus in a mesic region. We describe burrow geometry in response to seasonal weather conditions for two seasons (wet and dry). Interactions occurred between seasons and colony size for the size of the burrow systems, but not the shape of the burrow systems. The fractal dimension values of the burrow systems did not differ between seasons. Thus, the burrow complexity was dependent upon the number of mole rats present in the social group.

  19. The role of the water voles (Arvicola, Rodentia in the Quatemary

    Directory of Open Access Journals (Sweden)

    Ruiz Bustos, A.

    1999-04-01

    Full Text Available Arvicolids are rodents which have molars with a morphology formed by a sequence of enamel folds similar to the curve y = sin f(x. The morphology of the crown of the first lower molar (mi of living species of Arvicola (large voles is identified with six criteria, irrespective of tooth size. When rootless arvicolid fossil communities are analysed, it can be seen that the mi morphology of Arvicola is present in those communities represented by specimens of small size at the beginning of the Quaternary. Before this data was known, the presence of Arvicola communities could only be detected in the second half of the Quaternary, when the specimens were comparable to the large size characterising living species. The existence of communities of small-sized Arvicola at the beginning of the Quaternary implies that the mi of Arvicola undergoes a continuous and accelerated growth throughout the entire Quatemary, which allows representatives the genus to be used as a chronological tool. These data mean that it is necessary to change the concept of the genus Allophaiomys and to formulate a new classification to reflect evolutionary relationships of quatemary arvicolids.Los arvicólidos son roedores que tienen la morfología de la corona de los dientes formada por una secuencia de pliegues de esmalte que se asemeja a la curva y=sen f(x. Las especies actuales del género Arvicola cumplen en la morfología del molar mI, seis criterios que son independientes de la talla. El examen de las poblaciones de arvicólidos sin raíz, procedentes del Pleistoceno inferior, indica la existencia de molares con una morfología idéntica a la de los ejemplares vivos de Arvicola, pero con menor talla. La existencia de esta identidad permite proponer la hipótesis de poblaciones primitivas del género Arvicola con pequeña talla durante el Pleistoceno Inferior. Estas han pasado desapercibidas entre las poblaciones de Allophaiomys. a causa de su identidad morfológica entre ambos. La hipótesis de la existencia de Arvicola en el Pleistoceno Inferior supone un profundo cambio en el concepto de Allophaiomys como género y convierte la talla de Arvicola, por su continuo crecimiento durante todo el Pleistoceno, en un útil instrumento cronológico.

  20. Morphology of the tongue and characteristics of lingual papillae in Cuniculus paca (Rodentia: Cuniculidae

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    André Luiz Quagliatto Santos

    2013-11-01

    Full Text Available This paper describes the morphology of the tongue, its extrinsic muscles, and the characteristics of lingual papillae in Cuniculus paca. We used fifteen specimens from the Wild Animals Sector of Universidade Estadual Paulista (UNESP. In this species, the tongue is divided into three regions: root, body, and apex. The latter is delimited by the lingual frenum, which has the aspect of fibrous membrane. We also identified a median groove and a prominence on its dorsal surface. The extrinsic tongue muscles are the styloglossus, hyoglossus, genioglossus, geniohyoid, and milohyoid, the latter two are inserted into the hyoid apparatus. As for the presence of lingual papillae, we observed five papillae types in all specimens: filiform, fungiform, vallate, foliate, and conic. The filiform papillae are distributed throughout the apex surface and tongue body. They are caudally inclined throughout the body, until they are modified in the root region and form the conic papillae. The fungiform papillae are distributed in a large amount on the lingual apex, between the filiform papillae. This papilla type has a mushroom-like shape. Only two vallate papillae are located in the caudal portion of the lingual root, and they have an oval shape and are surrounded by a deep groove. The foliate papillae are observed in parallel grooves or slots located in the lateral portion of the tongue, between the vallate papillae and half of the intermolar prominence. In the tongue root, body, and apex we observed keratinized squamous stratified epithelium lining both the lingual papillae and the surface between them.

  1. Species composition and conservation of small mammals (Mammalia: Erinaceomorpha, Soricomorpha, Lagomorpha, Rodentia in Vrachanska Planina Mountains

    Directory of Open Access Journals (Sweden)

    NEDKO NEDYALKOV

    2016-05-01

    Full Text Available A review on the composition of the small mammals in Vrachanska Planina Mts. was completed using published and author’s data. A total of 27 species occur within the territory. All of the species found are typical for the region. The species with the highest conservation status, the European ground squirrel Spermophilus citellus, disappeared from the region in the early 1950s. In the last years activities on its recovery were carried out. We analyze the threats for the small mammals and propose conservation activities to improve their conservation status.

  2. The comparative gastrointestinal morphology of Jaculus jaculus (Rodentia) and Paraechinus aethiopicus (Erinaceomorpha).

    Science.gov (United States)

    Pereira, Daniella L; Walters, Jacklynn; Bennett, Nigel C; Alagaili, Abdulaziz N; Mohammed, Osama B; Kotzé, Sanet H

    2016-05-01

    Jaculus jaculus (Lesser Egyptian jerboa) and Paraechinus aethiopicus (Desert hedgehog) are small mammals which thrive in desert conditions and are found, among others, in the Arabian Peninsula. Jaculus jaculus is omnivorous while P. aethiopicus is described as being insectivorous. The study aims to describe the gastrointestinal tract (GIT) morphology of these animals which differ in diet and phylogeny. The GITs of J. jaculus (n = 8) and P. aethiopicus (n = 7) were weighed, photographed, and the length, basal surface areas, and luminal surface areas of each of the anatomically distinct gastrointestinal segments were determined. The internal aspects of each area were examined and photographed while representative histological sections of each area were processed to wax and stained using haematoxylin and eosin. Both species had a simple unilocular stomach which was confirmed as wholly glandular on histology sections. Paraechinus aethiopicus had a relatively simple GIT which lacked a caecum. The caecum of J. jaculus was elongated, terminating in a narrow cecal appendix which contained lymphoid tissue on histological examination. The internal aspect of the proximal colon of J. jaculus revealed distinct V-shaped folds. Stomach content analysis of J. jaculus revealed mostly plant and seed material and some insects, whereas P. aethiopicus samples showed plant material in addition to insects, indicating omnivorous feeding tendencies in areas where insects may be scarce.

  3. Chromosomal and C-heterochromatin Characterization of Arvicanthis niloticus (Rodentia: Murinae in Egypt

    Directory of Open Access Journals (Sweden)

    Mahmoud I. Shoulkamy

    2006-01-01

    Full Text Available The karyotype and C-banding pattern of the unstriped grass rat Arvicanthis niloticus from four localities in Egypt are presented. All individuals karyotyped, as a rule, have the same diploid number of 2n = 62 and autosomal Fundamental Number of aFN = 62. In addition, all chromosomes have a large centromeric block of fairly uniform size. However, an additional interstitial or telomeric small C-band is scored in some chromosomes. Nevertheless, frequent heteromorphism in the morphology and heterochromatin content of both the homologous chromosomes of the pair No. 1 and the X chromosome are scored in some individuals from the four localities and led to an aFN = 63. Accordingly, four forms or cytotypes, namely ANI-1a, ANI-1b, ANI-1c and ANI-1d, are recognized based on this variation, which is mostly attributed either to addition or deletion of a heterochromatic segment as a result of pericentric inversions. Of these four forms, the ANI-1a is considered ancestral for A. niloticus in Egypt and is closely similar to that of the Ethiopian A. dembeensis, regardless the contradiction concerned with nomenclature of the X chromosome, while the karyotypes of the other forms are synapomorphy of the form ANI-1a and showed as well a relative resemblance to those of the Ethiopian A. abyssinicus and A. blicki. Therefore, it is concluded that the genus Arvicanthis would be represented by an Egyptian-Ethiopian radiation (A. niloticus, A. dembeensis, A. abyssinicus and A. blicki and by a Central-Western African one, including the karyotypes described as A. centralis and A. solatus. Moreover, A. niloticus should be regarded no longer as a single species but as a cluster of several proper species.

  4. Bony labyrinth morphometry indicates locomotor adaptations in the squirrel-related clade (Rodentia, Mammalia)

    OpenAIRE

    2015-01-01

    The semicircular canals (SCs) of the inner ear detect angular acceleration and are located in the bony labyrinth of the petrosal bone. Based on high-resolution computed tomography, we created a size-independent database of the bony labyrinth of 50 mammalian species especially rodents of the squirrel-related clade comprising taxa with fossorial, arboreal and gliding adaptations. Our sampling also includes gliding marsupials, actively flying bats, the arboreal tree shrew and subterranean specie...

  5. Bony labyrinth morphometry indicates locomotor adaptations in the squirrel-related clade (Rodentia, Mammalia).

    Science.gov (United States)

    Pfaff, Cathrin; Martin, Thomas; Ruf, Irina

    2015-06-22

    The semicircular canals (SCs) of the inner ear detect angular acceleration and are located in the bony labyrinth of the petrosal bone. Based on high-resolution computed tomography, we created a size-independent database of the bony labyrinth of 50 mammalian species especially rodents of the squirrel-related clade comprising taxa with fossorial, arboreal and gliding adaptations. Our sampling also includes gliding marsupials, actively flying bats, the arboreal tree shrew and subterranean species. The morphometric anatomy of the SCs was correlated to the locomotion mode. Even if the phylogenetic signal cannot entirely be excluded, the main significance for functional morphological studies has been found in the diameter of the SCs, whereas the radius of curvature is of minor interest. Additionally, we found clear differences in the bias angle of the canals between subterranean and gliding taxa, but also between sciurids and glirids. The sensitivity of the inner ear correlates with the locomotion mode, with a higher sensitivity of the SCs in fossorial species than in flying taxa. We conclude that the inner ear of flying and gliding mammals is less sensitive due to the large information flow into this sense organ during locomotion.

  6. Intrageneric phylogeny of Acomys (rodentia, muridae) using mitochondrial gene cytochrome b.

    Science.gov (United States)

    Barome, P O; Monnerot, M; Gautun, J C

    1998-06-01

    This paper investigates interspecies relationships within the genus Acomys (spiny mice) by analyzing entire mitochondrial cytochrome b gene (1141 bp). This gene provides strong phylogenetic signal, as shown by high support of the topology obtained (bootstrap value and RNA support number). The phylogeny is congruent with inferences from allozymes for the species considered. Controversial taxonomy of Acomys cahirinus, dimidiatus, airensis, and ignitus is clarified, with their specific ranks confirmed on the basis of tree topology and nucleotide distances. Phylogenetic relationship between the undescribed species Acomys sp. from west Africa and A. airensis argue in favor of two distinct colonization events in this zone.

  7. Reproductive biology of Acomys cilicicus Spitzenberger, 1978 (Rodentia: Muridae) in Turkey

    OpenAIRE

    KIVANÇ, Erkut; EYİSON, Hatice MUTLU; KIRALP, Seda; EKİM, Okan

    2014-01-01

    The genus Acomys is represented by 19 species in a vast area in the African and eastern Mediterranean regions. Acomys cilicicus, belonging to the genus Acomys, is an endemic species in Turkey. In this study, by evaluating the reproductive data in laboratory conditions and the natural habitat of A. cilicicus, the reproductive biology of the species was researched in detail for the first time. The data concerning the reproduction of 1404 samples, reproduced from 1 male and 2 females in the labo...

  8. The origin of an unusual sex chromosome constitution in Acomys sp. (Rodentia, Muridae) from Tanzania.

    Science.gov (United States)

    Castiglia, Riccardo; Makundi, Rhodes; Corti, Marco

    2007-10-01

    This paper describes a case which presents an evident variation from the "standard" XX/XY sex chromosomal constitution in a rodent, Acomys sp. This species known to be found in three localities of East Africa has only recently been separated from A. spinosissimus, its closest relative. In our study, five specimens of Acomys sp. and eight specimens of A. spinosissimus were live-trapped in five localities. Comparisons between the two taxa assed by G-banding show a complete homology in the chromosomal shape and banding pattern for 29 pairs of chromosomes corresponding to the complete autosomal set of A. spinosissimus. However, while all the A. spinosissimus analysed have 2n = 60 and a XY-XX system, in Acomys sp. males and females constitute mosaics for sex chromosomes in the bone marrow cells. Females (2n = 59, 60) have an excess (97%) of aneuploid cells with one single giant X chromosome, and males (2n = 60, 61) show X0/XY cells occurring in somatic tissues and XY cells in the germinal lineage. In addition, an odd heterochromatic submetacentric chromosome was identified in all the cells examined in two males and a female of Acomys sp. Since this chromosome was not related to sex determination and it is not present in all the analysed specimens, it can be considered as a B chromosome. Finally, the in situ fluorescence hybridisation (FISH) with telomeric probes showed a very intense interstitial telomeric signal (ITS) at the medial part on the long heterochromatic arm of the X chromosome. This could be due to recent chromosomal rearrangement.

  9. Rattus norvegicus (Rodentia: Muridae) Infected by Leishmania (Leishmania) infantum (syn. Le. chagasi) in Brazil.

    Science.gov (United States)

    Lara-Silva, Fabiana de Oliveira; Barata, Ricardo Andrade; Michalsky, Erika Monteiro; Ferreira, Eduardo de Castro; Lopes, Maria Olímpia Garcia; Pinheiro, Aimara da Costa; Fortes-Dias, Consuelo Latorre; Dias, Edelberto Santos

    2014-01-01

    In the present study we surveyed the fauna of phlebotomine sand flies and small mammals in peridomestic areas from a Brazilian municipality where the American cutaneous leishmaniasis (ACL) is endemic. A total of 608 female phlebotomine sand flies were captured during nine months in 2009 and 2010. Seven different species were represented with 60% of them being Lutzomyia intermedia and Lu. whitmani, both incriminated vectors of ACL. Lu. longipalpis, a proven vector of visceral leishmaniasis (VL) was also captured at high proportion (12.8%). Genomic DNA analysis of 136 species-specific pools of female sand flies followed by molecular genotyping showed the presence of Leishmania infantum DNA in two pools of Lu. longipalpis. The same Leishmania species was found in one blood sample from Rattus norvegicus among 119 blood and tissue samples analysed. This is the first report of Le. infantum in R. norvegicus in the Americas and suggests a possible role for this rodent species in the zoonotic cycle of VL. Our study coincided with the reemergence of VL in Governador Valadares.

  10. Progonomys Schaub, 1938 and Huerzelerimys gen. nov. (Rodentia) : their evolution in Western Europe

    NARCIS (Netherlands)

    Mein, P.; Martín Suárez, E.; Agustí, J.

    1993-01-01

    In this paper the various species and populations attributed to the genus Progonomys Schaub, 1938 are revised. Valerymys Michaux, 1969 is considered to be synonymous with Occitanomys Michaux, 1969, since the type-species V. ellenbergeri (Thaler, 1966) was included in Occitanomys by Aguilar et al. (1

  11. A new species of Sciurodendrium (Nematoda: Heligmonellidae) in Sciurus aureogaster (Rodentia: Sciuridae) from Morelos, Mexico.

    Science.gov (United States)

    Falcón-Ordaz, Jorge; Lamothe-Argumedo, Marcos Rafael

    2006-06-01

    Sciurodendrium bravohollisae n. sp. (Heligmonellidae) is described as an intestinal parasite of 2 squirrels, Sciurus aureogaster Cuvier, 1829, collected from Los Robles, Municipio de Tlalnepantla, Morelos State, Mexico. The new species differs from all other congeners in possessing a very well-developed and sacciform genital cone. This is the seventh species described for the genus and the first one recorded in Mexico.

  12. VARIACIÓN CARIOLÓGICA EN DIFERENTES FENOTIPOS DE Sciurus granatensis (RODENTIA, SCIURIDAE

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    CAROLINA ARANGO

    2007-01-01

    Full Text Available Siete ejemplares de Sciurus granatensis (ardilla colombiana de diferentes fenotipos según color, rescatadas del tráfico ilegal de fauna silvestre de Colombia fueron estudiadas. Mediante técnicas convencionales de bandeo cromosómico G, C, Q, R y NOR se estableció su cariotipo 2n=42. Se encontraron tres cariomorfos de acuerdo al Nú- mero Fundamental (NF y características propias de cada uno de los complementos ocasionadas por distintos rearreglos cromosómicos, lo cual sugiere que S. granatensis es un complejo de especies. No se observó relación entre cariotipo y fenotipo. La variación en el color del pelaje se debe probablemente a las condiciones ambientales.

  13. Development of the central nervous system in guinea pig (Cavia porcellus, Rodentia, Caviidae

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    Fernanda Menezes de Oliveira e Silva

    Full Text Available Abstract: This study describes the development of the central nervous system in guinea pigs from 12th day post conception (dpc until birth. Totally, 41 embryos and fetuses were analyzed macroscopically and by means of light and electron microscopy. The neural tube closure was observed at day 14 and the development of the spinal cord and differentiation of the primitive central nervous system vesicles was on 20th dpc. Histologically, undifferentiated brain tissue was observed as a mass of mesenchymal tissue between 18th and 20th dpc, and at 25th dpc the tissue within the medullary canal had higher density. On day 30 the brain tissue was differentiated on day 30 and the spinal cord filling throughout the spinal canal, period from which it was possible to observe cerebral and cerebellar stratums. At day 45 intumescences were visualized and cerebral hemispheres were divided, with a clear division between white and gray matter in brain and cerebellum. Median sulcus of the dorsal spinal cord and the cauda equina were only evident on day 50. There were no significant structural differences in fetuses of 50 and 60 dpc, and animals at term were all lissencephalic. In conclusion, morphological studies of the nervous system in guinea pig can provide important information for clinical studies in humans, due to its high degree of neurological maturity in relation to its short gestation period, what can provide a good tool for neurological studies.

  14. Phylogenetic relationships of extant zokors (Myospalacinae) (Rodentia, Spalacidae) inferred from mitochondrial DNA sequences.

    Science.gov (United States)

    Su, Junhu; Ji, Weihong; Wang, Jing; Gleeson, Dianne M; Zhou, Janwei; Hua, Limin; Wei, Yanming

    2014-04-01

    In this study, we use three mitochondrial markers, cytochrome b gene (Cyt b), NADH dehydrogenase subunit 4 (ND4) and control region (D-loop) to investigate the phylogenetic relationships of extant zokor species in Mysopalacinae. The phylogenetic tree constructed based on Cyt b strongly supports the monophyly genera Eospalax and Myospalax with E. fontanierii being the most ancient species in Eospalax. Further phylogenetic analyses of four species of Eospalax based on ND4 and D-loop sequences revealed two clades that correspond to two geographical distributions. The basal clade includes E. cansus which is mainly found on Loess Plateau (LP) and another clade including E. baileyi, E. smithii and E. rufescens that inhabits areas above 2000 m on Qinghai-Tibetan Plateau (QTP) and Qinling Mountains. Geographical events of QTP and LP may have played a major role in the diversification and evolution of Mysopalacinae.

  15. Heterakis spumosa Schneider, 1866 (Nematoda: Heterakidae in Rattus norvegicus (Rodentia: Muridae in Ica, Peru

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    Rufino Cabrera Ch.

    2014-06-01

    Full Text Available In this paper Heterakis spumosa Schneider, 1866 is redescribed. It is a parasitic heterakid nematoda living in the caecum of murid rodent, Rattus norvegícus "gray rat" from district of Parcona, province of Ica, Peru.

  16. Note on the Giant Woolly Gliding Squirrel Eupetaurus cinereus (Mammalia: Rodentia: Sciuridae in northern Pakistan

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    Jaffar Ud Din

    2015-07-01

    Full Text Available The Woolly Gliding Squirrel Eupetaurus cinereus is an extremely rare, localized, and endangered mammal and may constitute one of the endemic species of Pakistan. The species was rediscovered in northern Pakistan in the mid-1990s after a 70-year absence of records. All the previous information regarding this giant squirrel was limited to museum specimens, collected mostly from areas presently in northern Pakistan in the late 1800s. Sighting of the species is extremely challenging owing to its nocturnal behavior, low densities and the inhospitable terrain it is reported from. Here we report detailed information about the species collected during the rescue of a young male individual from Gilgit City followed by its successful release in its natural habitat. We report that the species is still facing human-induced threats and may disappear from the mountains of northern Pakistan if informed management measures are not taken. Moreover, the occurrence of the species outside its core distribution range, i.e., districts Gilgit and Diamer, still remains questionable; therefore, it is recommended that further in-depth research studies be undertaken to determine the status of the species across the entire reported range. 

  17. Ecology of the interaction between Ixodes loricatus (Acari: Ixodidae) and Akodon azarae (Rodentia: Criceridae).

    Science.gov (United States)

    Colombo, Valeria C; Nava, Santiago; Antoniazzi, Leandro R; Monje, Lucas D; Racca, Andrea L; Guglielmone, Alberto A; Beldomenico, Pablo M

    2015-10-01

    The present study explores associations of different factors (i.e. host parameters, presence of other ectoparasites and [mainly biotic] environmental factors) with burdens of Ixodes loricatus immature stages in one of its main hosts in Argentina, the rodent Akodon azarae. For 2 years, rodents were trapped and sampled monthly at 16 points located in four different sites in the Parana River Delta region. Data were analysed with generalized linear mixed models with a negative binomial response (counts of larvae or nymphs). The independent variables assessed were (a) environmental: trapping year, presence of cattle, type of vegetation, rodent abundance; (b) host parameters: body length, sex, body condition, blood cell counts, natural antibody titers and (c) co-infestation with other ectoparasites. Two-way interaction terms deemed a priori as relevant were also included in the analysis. Most of the associations investigated were found significant, but in general, the direction and magnitude of the associations were context-dependent. An exception was the presence of cattle, which was consistently negatively associated with both larvae and nymphs independently of all other variables considered and had the strongest effect on tick burdens. Mites, fleas and Amblyomma triste were also significantly associated (mostly positively) with larval and nymph burdens, and in many cases, they influenced associations with environmental or host factors. Our findings strongly support that raising cattle may have a substantial impact on the dynamics of I. loricatus and that interactions within the ectoparasite community may be an important-but generally ignored-driver of tick dynamics.

  18. Genetic diversity and population structure of the Guinea pig (Cavia porcellus, Rodentia, caviidae in Colombia

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    William Burgos-Paz

    2011-01-01

    Full Text Available The aim was to establish the genetic diversity and population structure of three guinea pig lines, from seven production zones located in Nariño, southwest Colombia. A total of 384 individuals were genotyped with six microsatellite markers. The measurement of intrapopulation diversity revealed allelic richness ranging from 3.0 to 6.56, and observed heterozygosity (Ho from 0.33 to 0.60, with a deficit in heterozygous individuals. Although statistically significant (p < 0.05, genetic differentiation between population pairs was found to be low. Genetic distance, as well as clustering of guinea-pig lines and populations, coincided with the historical and geographical distribution of the populations. Likewise, high genetic identity between improved and native lines was established. An analysis of group probabilistic assignment revealed that each line should not be considered as a genetically homogeneous group. The findings corroborate the absorption of native genetic material into the improved line introduced into Colombia from Peru. It is necessary to establish conservation programs for native-line individuals in Nariño, and control genealogical and production records in order to reduce the inbreeding values in the populations.

  19. Notocotylus loeiensis n. sp. (Trematoda: Notocotylidae from Rattus losea (Rodentia: Muridae in Thailand

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    Chaisiri K.

    2011-02-01

    Full Text Available Notocotylus loeiensis n. sp. (Trematoda: Notocotylidae is described from the cecum of the lesser rice field rat (Rattus losea, from Loei Province in Thailand with a prevalence of 9.1% (eight of 88 rats infected. The new species differs from previously described Notocotylus species mainly by the extreme prebifurcal position of the genital pore and the number of ventral papillae. This is the first description at the species level of Notocotylus from mammals in Southeast Asia.

  20. Habitats, population densities, and social structure of capybaras (Hydrochaeris Hydrochaeris, Rodentia in the Pantanal, Brazil

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    Cleber J.R. Alho

    1987-01-01

    Full Text Available (1 The Pantanal is the central portion of a sunken flat plain bordering the upper Paraguay river, with an area of 140,000 km². Seasonal floods begin in January and end in April. From May to October the land dries out and campos (grassland formations and scattered pools appear. (2 Typical capybara habitat in the Pantanal is composed of three components: the water, a patch of forest, and a grass field for foraging. Highest densities of capybaras (14 individuals/km² were found during the rainy season when the available space for capybaras was reduced due to the flooding. Areas without ponds or creeks presented low densities (from 0.38 to 0.84 capybaras/km². Group sizes ranged from 2 to 49 individuals (x = 9.48. (3 Reproduction occurred year-round and young of different ages were seen throughout the year. However, the principal recruitment of young to the population was observed in July-August. While the females took turns in caring for young of different ages, probably the offspring of mothers who are sisters in the same social groups, the males competed intensively with each other for access to breeding females. The male's reproductive success appears to be limited to the number of breeding females that males have access to in the social group.

  1. Karyotypic analysis in species of the genus Dasyprocta (Rodentia: Dasyproctidae found in Brazilian Amazon

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    ROSEMAR S. L. RAMOS

    2003-03-01

    Full Text Available A total of 30 animals of the genus Dasyprocta were cytogenetically studied. They belong to the following species: D. prymnolopha (N=20, D. leporina (N=6, D. fuliginosa (N=1 and Dasyprocta sp. (N=3 (Dasyproctidae, Hystricognathi. Cell suspensions were obtained by peripheral blood culture, besides bone marrow and spleen cells, from D. prymnolopha and D. leporina. The diploid number was 64/65 for all samples. The karyotypes showed similarity, and chromosomal polymorphism was not detected by Giemsa conventional staining and G banding. The constitutive heterochromatin distribution at the pericentromeric region of all the chromosomes was similar in all species. D. prymnolopha, D. leporina and Dasyprocta sp. presented variation in the heterochromatical block size at one of the homologues of the A18 pair. D. fuliginosa presented the heterochromatin uniformly distributed in all chromosomes. There was not variation in the NORs pattern in the species studied.Foram estudados citogeneticamente um total de 30 animais das espécies D. prymnolopha (N=20, D. leporina (N=6, D. fuliginosa (N=1 e Dasyprocta sp. (N=3 (Dasyproctidae, Histricognathi. As preparações cromossômicas foram obtidas do cultivo de sangue periférico, além de medula óssea e baço em D. prymnolopha e D. leporina. O número diplóide foi de 64/65 em todos os exemplares. O cariótipo mostrou similaridade, não sendo detectado, através de coloração convencional de giemsa e de banda G, polimorfismo cromossômico em qualquer uma das espécies estudadas. A distribuição da heterocromatina constitutiva na região pericentromérica de todos os cromossomos foi similar nas quatro espécies. D. prymnolopha, D. leporina e Dasyprocta sp. apresentaram variação no tamanho do bloco heterocromático em um dos homólogos do par A18. D. fuliginosa apresentou a heterocromatina uniformemente distribuída em todos os cromossomos. Não houve variação no padrão das RONs entre as esp��cies estudadas.

  2. Homomorphic sex chromosomes and the intriguing Y chromosome of Ctenomys rodent species (Rodentia, Ctenomyidae).

    Science.gov (United States)

    Suárez-Villota, Elkin Y; Pansonato-Alves, José C; Foresti, Fausto; Gallardo, Milton H

    2014-01-01

    Unlike the X chromosome, the mammalian Y chromosome undergoes evolutionary decay resulting in small size. This sex chromosomal heteromorphism, observed in most species of the fossorial rodent Ctenomys, contrasts with the medium-sized, homomorphic acrocentric sex chromosomes of closely related C. maulinus and C. sp. To characterize the sequence composition of these chromosomes, fluorescent banding, self-genomic in situ hybridization, and fluorescent in situ hybridization with an X painting probe were performed on mitotic and meiotic plates. High molecular homology between the sex chromosomes was detected on mitotic material as well as on meiotic plates immunodetected with anti-SYCP3 and anti-γH2AX. The Y chromosome is euchromatic, poor in repetitive sequences and differs from the X by the loss of a block of pericentromeric chromatin. Inferred from the G-banding pattern, an inversion and the concomitant prevention of recombination in a large asynaptic region seems to be crucial for meiotic X chromosome inactivation. These peculiar findings together with the homomorphism of Ctenomys sex chromosomes are discussed in the light of the regular purge that counteracts Muller's ratchet and the probable mechanisms accounting for their origin and molecular homology.

  3. Two new species of Hymenolepis (Cestoda: Hymenolepididae) from Spalacidae and Muridae (Rodentia) from eastern Palearctic.

    Science.gov (United States)

    Makarikov, Arseny A; Tkach, Vasyl V

    2013-03-01

    Previously unrecognized species of the genus Hymenolepis are described based on specimens from spalacid and murid (Murinae) rodents. Hymenolepis rymzhanovi sp. nov. from the Siberian zokor, Myospalax myospalax (Laxmann), from East Kazakhstan, and H. apodemi sp. nov. from Eurasian field mice, Apodemus peninsulae (Thomas), A. uralensis (Pallas) and A. agrarius (Pallas), from the south of Russian Far East, western Siberia and south-eastern Kazakhstan are characterized. The new species differ from other species of the genus by the morphology of the scolex, the relative position and length of the cirrus-sac and the relative position and arrangement of the testes. Differential criteria of species of Hymenolepis (sensu stricto) are also discussed.

  4. Cryptic speciation and chromosomal repatterning in the South African climbing mice Dendromus (Rodentia, Nesomyidae).

    Science.gov (United States)

    Solano, Emanuela; Taylor, Peter J; Rautenbach, Anita; Ropiquet, Anne; Castiglia, Riccardo

    2014-01-01

    We evaluate the intra- and interspecific diversity in the four South African rodent species of the genus Dendromus. The molecular phylogenetic analysis on twenty-three individuals have been conducted on a combined dataset of nuclear and mitochondrial markers. Moreover, the extent and processes underlying chromosomal variation, have been investigated on three species by mean of G-, C-bands, NORs and Zoo-FISH analysis. The molecular analysis shows the presence of six monophyletic lineages corresponding to D. mesomelas, D. mystacalis and four lineages within D. cfr. melanotis with high divergence values (ranges: 10.6% - 18.3%) that raises the question of the possible presence of cryptic species. The first description of the karyotype for D. mesomelas and D. mystacalis and C- and G- banding for one lineage of D. cfr. melanotis are reported highlighting an extended karyotype reorganization in the genus. Furthermore, the G-banding and Zoo-FISH evidenced an autosome-sex chromosome translocation characterizing all the species and our timing estimates this mutation date back 7.4 mya (Late Miocene). Finally, the molecular clock suggests that cladogenesis took place since the end of Miocene to Plio-Pleistocene, probably due to ecological factors, isolation in refugia followed by differential adaptation to the mesic or dry habitat.

  5. Seasonal changes in body composition of Ctenomys talarum (Rodentia: Octodontidae): an herbivore subterranean rodent.

    Science.gov (United States)

    del Valle, Juana C; López Mañanes, Alejandra A; Busch, Cristina

    2006-09-01

    Ctenomys talarum is a subterranean herbivorous rodent whose burrow systems exhibit particular characteristics, distinct from other subterranean environments. We studied seasonal variation in body composition of C. talarum in relation to energetic requirements. Body lipid content seasonally changed in C. talarum, related to reproductive cycle and thermorregulatory mechanisms. A decrease in protein body content was found only in spring. Ash content of females was lowest when most of them are in post partum estro. Observed variations in water body content could be associated with plant water content and/or metabolic regulation. Our results show the occurrence of seasonal variations in body composition in C. talarum, which could be related to the high cost of reproduction and the subterranean life style of this species.

  6. First Miocene rodent from Lebanon provides the 'missing link' between Asian and African gundis (Rodentia: Ctenodactylidae).

    Science.gov (United States)

    López-Antoñanzas, Raquel; Knoll, Fabien; Maksoud, Sibelle; Azar, Dany

    2015-08-07

    Ctenodactylinae (gundis) is a clade of rodents that experienced, in Miocene time, their greatest diversification and widest distribution. They expanded from the Far East, their area of origin, to Africa, which they entered from what would become the Arabian Peninsula. Questions concerning the origin of African Ctenodactylinae persist essentially because of a poor fossil record from the Miocene of Afro-Arabia. However, recent excavations in the Late Miocene of Lebanon have yielded a key taxon for our understanding of these issues. Proafricanomys libanensis nov. gen. nov. sp. shares a variety of dental characters with both the most primitive and derived members of the subfamily. A cladistic analysis demonstrates that this species is the sister taxon to a clade encompassing all but one of the African ctenodactylines, plus a southern European species of obvious African extraction. As such, Proafricanomys provides the 'missing link' between the Asian and African gundis.

  7. Clues on Syntenic Relationship among Some Species of Oryzomyini and Akodontini Tribes (Rodentia: Sigmodontinae)

    Science.gov (United States)

    Suárez, Pablo; Nagamachi, Cleusa Yoshiko; Lanzone, Cecilia; Malleret, Matias Maximiliano; O’Brien, Patricia Caroline Mary; Ferguson-Smith, Malcolm Andrew; Pieczarka, Julio Cesar

    2015-01-01

    Sigmodontinae rodents represent one of the most diverse and complex components of the mammalian fauna of South America. Among them most species belongs to Oryzomyini and Akodontini tribes. The highly specific diversification observed in both tribes is characterized by diploid complements, which vary from 2n = 10 to 86. Given this diversity, a consistent hypothesis about the origin and evolution of chromosomes depends on the correct establishment of synteny analyzed in a suitable phylogenetic framework. The chromosome painting technique has been particularly useful for identifying chromosomal synteny. In order to extend our knowledge of the homeological relationships between Akodontini and Oryzomyini species, we analyzed the species Akodon montensis (2n = 24) and Thaptomys nigrita (2n = 52) both from the tribe Akodontini, with chromosome probes of Hylaeamys megacephalus (2n = 54) of the tribe Oryzomyini. The results indicate that at least 12 of the 26 autosomes of H. megacephalus show conserved synteny in A. montensis and 14 in T. nigrita. The karyotype of Akodon montensis, as well as some species of the Akodon cursor species group, results from many chromosomal fusions and therefore the syntenic associations observed probably represent synapomorphies. Our finding of a set of such associations revealed by H. megacephalus chromosome probes (6/21; 3/25; 11/16/17; and, 14/19) provides phylogenetic information for both tribes. An extension of these observations to other members of Akodontini and Oryzomyini tribes should improve our knowledge about chromosome evolution in both these groups. PMID:26642204

  8. Esqueletogênese em punaré (Thrichomys laurentinus- Rodentia, Echimyidae

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    Phelipe O. Favaron

    Full Text Available Resumo: O objetivo deste estudo foi descrever o desenvolvimento do esqueleto do punaré (Thrichomys laurentinus. Para tanto, foram utilizados 11 embriões e 12 fetos em diferentes estágios de desenvolvimento, sendo divididos em 4 grupos de acordo com o período gestacional. As amostras foram obtidas no Centro de Multiplicação de Animais Silvestres da Universidade Federal Rural do Semi-Árido, Mossoró-RN, Brasil. Após fixados em formol (10% ou glutaraldeído (2,5%, foi realizada a analise morfológica com auxílio de lupa, sendo as características macroscópicas fotodocumentadas. Análises de raios-x e coloração por alizarina red foram realizadas para melhor compreensão do desenvolvimento ósseo. Nas análises de raio-x os embriões não apresentaram nenhuma radiopacidade, ao contrário dos fetos que apresentavam radiopacidade gradual ao longo dos grupos. No grupo II houve aumento de radiopacidade na região da coluna vertebral e das regiões mandibular e maxilar. No grupo III a radiopacidade estava aumentada nos membros pélvicos, nas costelas e na região frontal e no grupo IV nos membros torácicos e nas regiões occipital, temporal e frontal do crânio. Tais características foram confirmadas pelas analises histológicas e pela técnica de Alizarina Red. Com isso podemos concluir que o conhecimento acerca da embriologia do sistema ósseo normal é fundamental para o entendimento dos efeitos adversos causados pela nutrição e uso de drogas durante o desenvolvimento.

  9. Clues on Syntenic Relationship among Some Species of Oryzomyini and Akodontini Tribes (Rodentia: Sigmodontinae.

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    Pablo Suárez

    Full Text Available Sigmodontinae rodents represent one of the most diverse and complex components of the mammalian fauna of South America. Among them most species belongs to Oryzomyini and Akodontini tribes. The highly specific diversification observed in both tribes is characterized by diploid complements, which vary from 2n = 10 to 86. Given this diversity, a consistent hypothesis about the origin and evolution of chromosomes depends on the correct establishment of synteny analyzed in a suitable phylogenetic framework. The chromosome painting technique has been particularly useful for identifying chromosomal synteny. In order to extend our knowledge of the homeological relationships between Akodontini and Oryzomyini species, we analyzed the species Akodon montensis (2n = 24 and Thaptomys nigrita (2n = 52 both from the tribe Akodontini, with chromosome probes of Hylaeamys megacephalus (2n = 54 of the tribe Oryzomyini. The results indicate that at least 12 of the 26 autosomes of H. megacephalus show conserved synteny in A. montensis and 14 in T. nigrita. The karyotype of Akodon montensis, as well as some species of the Akodon cursor species group, results from many chromosomal fusions and therefore the syntenic associations observed probably represent synapomorphies. Our finding of a set of such associations revealed by H. megacephalus chromosome probes (6/21; 3/25; 11/16/17; and, 14/19 provides phylogenetic information for both tribes. An extension of these observations to other members of Akodontini and Oryzomyini tribes should improve our knowledge about chromosome evolution in both these groups.

  10. [Morphological variability of Microtus oeconomus pallas (Rodentia, Rrvicolidae) from Baikal region].

    Science.gov (United States)

    Pozdniakov, A A; Litvinov, Iu N; Demidovich, P A

    2006-01-01

    The analysis of morphological variability of the ten samples of Microtus oeconomus from islands of Baikal and adjacent regions gas shown, that island samples differ from continental ones by complex of parameters, defining proportions of a skuul, mainly, proportions of an auditory region. Island samples also differ higher indexes of complexity and asymmetry of morphotypes of the third upper molar. An environment of the Baikal islands differ absence of the damp habitats preferred Microtus oeconomus, and also colder microclimate that has caused forming original morphological character of island micropopulations.

  11. The role of seed mass on the caching decision by agoutis, Dasyprocta leporina (Rodentia: Agoutidae

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    Mauro Galetti

    2010-06-01

    Full Text Available It has been shown that the local extinction of large-bodied frugivores may cause cascading consequences for plant recruitment and overall plant diversity. However, to what extent the resilient mammals can compensate the role of seed dispersal in defaunated sites is poorly understood. Caviomorph rodents, especially Dasyprocta spp., are usually resilient frugivores in hunted forests and their seed caching behavior may be important for many plant species which lack primary dispersers. We compared the effect of the variation in seed mass of six vertebrate-dispersed plant species on the caching decision by the red-rumped agoutis Dasyprocta leporina Linnaeus, 1758 in a land-bridge island of the Atlantic forest, Brazil. We found a strong positive effect of seed mass on seed fate and dispersal distance, but there was a great variation between species. Agoutis never cached seeds smaller than 0.9 g and larger seeds were dispersed for longer distances. Therefore, agoutis can be important seed dispersers of large-seeded species in defaunated forests.

  12. A new karyotype for the genus Cavia from a southern island of Brazil (Rodentia - Caviidae

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    A. Gava

    1998-03-01

    Full Text Available Intraspecific karyotype variation in mammal species is very common and often caused by centromeric fusion of acrocentric chromosomes. We describe here a new karyotype 2n = 62 (FN = 112 for the genus Cavia from the Moleques do Sul Islands, of the southern coast of Brazil. We analyzed two male and four female karyotypes that had twenty-four biarmed pairs and six pairs of acrocentric chromosomes. The sexual pair consisted of a metacentric X-chromosome and a large acrocentric Y. C-bands were found in the centromeric and pericentromeric regions of almost all chromosomes, except for some small biarmed and acrocentric ones. Nucleolus organizer regions appeared in two biarmed chromosomes, and G-banding patterns were also seen.RESUMO A variação cariotípica nas espécies de mamíferos é bastante comum e geralmente causada pela fusão de cromossomos acrocêntricos. Foi descrito neste trabalho um novo cariótipo, com 2n = 62 e FN = 112, para o gênero Cavia proveniente das ilhas Moleques do Sul, da costa sul do Brasil. Foram analisados os cariótipos de dois machos e quatro fêmeas que possuiam 24 pares de cromossomos com dois braços e seis pares de acrocêntricos. O par sexual era constituído por um cromossomo X metacêntrico grande e um Y acrocêntrico. As bandas C estavam localizadas nas regiões centroméricas e pericentroméricas da maioria dos cromossomos, com exceção de alguns acrocêntricos e os cromossomos de dois braços menores. As regiões organizadoras de nucléolo ocorreram em dois cromossomos com dois braços e o padrão de bandamento G foi também apresentado.

  13. Reproduction, development and growth of Akodon lindberghi (Hershkovitz, 1990 (Rodentia, Muridae, Sigmodontinae raised in captivity

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    V De Conto

    Full Text Available The reproduction, development and growth of Akodon lindberghi were studied in captivity. The colony was derived from animals captured in Simão Pereira, Minas Gerais state, which represents a new area of geographical distribution known for this species. Twelve males and twelve females were crossed, producing 144 young in 53 litters. Post-partum oestrus was observed and gestation length was estimated in 23 days. Litter size ranged from 1 to 4 with a mean of 2.72 (SD = 0.97, n = 53 and modal size of 3. Sexual dimorphism was neither present in body mass at birth nor at weaning. There was a significant negative correlation between litter size and mass at birth or weaning. Permanent emergence of adult external appearance occurred at 15 days. Puberty for males and females was 43 and 42 days, respectively, and the first fecundation event for two females was recorded at 47 and 54 days of age. The weight growth was described by fitting a Gompertz model. No significant difference was found in any parameter of growth curves for males and females. Measurements (head-body, tail, hind foot and internal and external ear lengths obtained for adult individuals also did not reveal the presence of sexual dimorphism.

  14. Fleas (Siphonaptera) in the Nests of Dormice (Gliridae: Rodentia) in Lithuania.

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    Lipatova, I; Stanko, M; Paulauskas, A; Spakovaite, S; Gedminas, V

    2015-05-01

    Negative effects of flea (Siphonaptera) parasitism on the host may be expressed in different ways. The aim of this study was to assess distribution of the flea fauna in nests of dormice in Lithuania. Nests of Glis glis (L.), Dryomys nitedula (Pallas), and Muscardinus avellanarius (L.) were collected from nest boxes in 2012 and 2013. Fleas were collected from nests in the laboratory and put into plastic tubes with 70% ethanol. Flea species were identified using morphological keys. From 400 nest boxes, 112 nests of dormice were collected from eight sites from mixed forests of central Lithuania. Twenty-three nests of G. glis were collected from nest boxes, with 16 of them containing 286 fleas belonging to four species: Ceratophyllus sciurorum (Schrank) (259), C. gallinae (Schrank) (23), Hystrichopsylla talpae (Curtis) (3), and Megabothris turbidus (Rothschild) (1). Fourteen nests of M. avellanarius were collected from nest boxes, 4 of which contained 224 fleas belonging to two species: C. sciurorum (221) and C. gallinae (3). Twenty-four nests of D. nitedula were collected from nest boxes, including 17 containing 207 fleas belonging to two species: C. sciurorum (205) and C. gallinae (2). Fifty-one nests of undetermined dormice species also were collected from nest boxes, 12 of them contained 395 fleas belonging to three species: C. sciurorum (374), Ctenophthalmus agyrtes (Heller) (19), and Ctenophthalmus assimilis (Taschenberg) (2). C. sciurorum was a predominant species in the nests of dormice. The occurrence of C. gallinae was documented in Lithuania for the first time.

  15. Isozyme and allozyme markers distinguishing two morphologically similar, medically important Mastomys species (Rodentia: Muridae

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    Van der Bank Herman FH

    2001-09-01

    Full Text Available Abstract Background Two common southern African mice species, Mastomys coucha and M. natalensis, are widely distributed throughout the subregion and overlap in many areas. They also share a high degree of morphological similarity, making them impossible to distinguish in the field at present. These multimammate mice are documented carriers of serious disease vectors causing Lassa fever, plague and encephalomyocarditis, which coupled to their cohabitation with humans in many areas, could pose a significant health risk. A preliminary study reported the presence of isozyme markers at three loci (GPI-2, PT-2, -3 in one population each of M. coucha and M. natalensis. Two additional populations (from the Vaal Dam and Richards Bay were sampled to determine the reliability of these markers, and to seek additional genetic markers. Results Fifteen proteins or enzymes provided interpretable results at a total of 39 loci. Additional fixed allele differences between the species were detected at AAT-1, ADH, EST-1, PGD-1, Hb-1 and -2. Average heterozygosities for M. coucha and M. natalensis were calculated as 0.018 and 0.032 respectively, with a mean genetic distance between the species of 0.26. Conclusions The confirmation of the isozyme and the detection of the additional allozyme markers are important contributions to the identification of these two medical and agricultural pest species.

  16. Ectoparasites of the critically endangered insular cavy, Cavia intermedia (Rodentia: Caviidae, southern Brazil

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    André Luis Regolin

    2015-04-01

    Full Text Available Cavia intermedia is a rodent species critically endangered and is found only on a 10 hectare island off the southern Brazilian coast. To identify the ectoparasites of C. intermedia, 27 specimens (14 males and 13 females, representing approximately 65% of the estimated total population, were captured and examined. A total of 1336 chewing lice of two species were collected: Gliricola lindolphoi (Amblycera: Gyropidae and Trimenopon hispidum (Amblycera: Trimenoponidae. In addition, chiggers Arisocerus hertigi (Acari: Trombiculidae and Eutrombicula sp. (Acari: Trombiculidae were collected from the ears of all captured animals. This low species richness compared to those for other Cavia species is expected for island mammals. Although the results presented here are not conclusive about the relationship between C. intermedia and ectoparasites, this low species richness found might be reflected in a low level of investment by the hosts in the basal immune defense, since investments in white blood cell production by mammals are influenced by the diversity of parasites in the environment. Additionally, considering that it might result in host vulnerability to other parasites that might be introduced through exotic or migratory host species, the monitoring of C. intermedia, including parasitological and immunological assessments, is recommended as a key component of conservation efforts.

  17. LATE PLEISTOCENE RODENTS (MAMMALIA: RODENTIA FROM THE BARANICA CAVE NEAR KNJAZEVAC (EASTERN SERBIA: SYSTEMATICS AND PALAEOECOLOGY

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    KATARINA BOGICEVIC

    2011-07-01

    Full Text Available Baranica is a cave in the Balkan mountain range in the eastern part of Serbia. It contains four layers of sediments of Quaternary age. The Upper Pleistocene deposits (layers 2-4 have yielded a rich and diverse assemblage of vertebrate fauna, including fish, amphibians, reptiles, birds, and small and large mammals. In this work, preliminary results of a study of the rodent fauna from the Upper Pleistocene deposits of the Baranica Cave (Knjazevac, eastern Serbia are presented. The fossil material comes from the 1995 archaeological excavation. The remains of 10 rodent species are described herein: Spermophilus cf. citelloides, Castor fiber, Sicista subtilis, Cricetulus migratorius, Cricetus cricetus, Mesocricetus newtoni, Apodemus ex gr. sylvaticus-flavicollis, Spalax leucodon, Dryomys nitedula, and Muscardinus avellanarius. Along with eight vole species, this makes altogether 18 species of rodents found in this locality. Both layers 2 and 4 (layer 3 is very poor in fossils have yielded a rodent fauna typical for the cold periods of the Late Pleistocene on the Balkan Peninsula, with a prevalence of open and steppe inhabitants, but some forest dwellers were also present. The assemblages from these layers are similar, but there are some differences in the composition of the fauna, which may indicate a slight shift towards drier conditions. They have also been compared to rodent associations from some Serbian and Bulgarian localities of the same age and their similarities and differences are discussed. SHORT NOTE-NOTA BREVE

  18. Re-evaluation of Sinocastor (Rodentia: Castoridae with implications on the origin of modern beavers.

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    Natalia Rybczynski

    Full Text Available The extant beaver, Castor, has played an important role shaping landscapes and ecosystems in Eurasia and North America, yet the origins and early evolution of this lineage remain poorly understood. Here we use a geometric morphometric approach to help re-evaluate the phylogenetic affinities of a fossil skull from the Late Miocene of China. This specimen was originally considered Sinocastor, and later transferred to Castor. The aim of this study was to determine whether this form is an early member of Castor, or if it represents a lineage outside of Castor. The specimen was compared to 38 specimens of modern Castor (both C. canadensis and C. fiber as well as fossil specimens of C. fiber (Pleistocene, C. californicus (Pliocene and the early castorids Steneofiber eseri (early Miocene. The results show that the specimen falls outside the Castor morphospace and that compared to Castor, Sinocastor possesses a: 1 narrower post-orbital constriction, 2 anteroposteriorly shortened basioccipital depression, 3 shortened incisive foramen, 4 more posteriorly located palatine foramen, 5 longer rostrum, and 6 longer braincase. Also the specimen shows a much shallower basiocciptal depression than what is seen in living Castor, as well as prominently rooted molars. We conclude that Sinocastor is a valid genus. Given the prevalence of apparently primitive traits, Sinocastor might be a near relative of the lineage that gave rise to Castor, implying a possible Asiatic origin for Castor.

  19. Spatial use of rodents (Rodentia: Mammalia host body surface by ectoparasites

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    E. B. BITTENCOURT

    Full Text Available We studied the ectoparasite and the Amblyopinini beetle fauna associated with four small mammal species of the Atlantic Rainforest of Ilha Grande, an island located off the southern Rio de Janeiro State Coast, Southeastern Brazil, analyzing to what extent the parasites were specific to each region of the host body. During the study, a total of 90 individual rodents were captured: 61 Proechimys iheringi Thomas, 1911 (Echymyidae, 22 Sciurus aestuans (Thomas, 1901 (Sciuridae, 4 Oxymycterus sp. (Waterhouse, 1837, and 2 Nectomys squamipes (Brants, 1827 (Sigmodontinae. The data showed that the ectoparasites and Amblyopinini on some rodent hosts in Ilha Grande tend to prefer particular host body sites, and that some ectoparasite species sites may overlap owing to their inaccessibility to the host.

  20. Accelerated molecular evolution in Microtus (Rodentia) as assessed via complete mitochondrial genome sequences.

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    Triant, Deborah A; Dewoody, J Andrew

    2006-01-01

    Microtus is one of the most taxonomically diverse mammalian genera, including over 60 extant species. These rodents have evolved rapidly, as the genus originated less than 2 million years ago. If these numbers are taken at face value, then an average of 30 microtine speciation events have occurred every million years. One explanation for the rapid rate of cladogenesis in Microtus could be the karyotypic differentiation exhibited across the genus: diploid numbers range from 17 to 64. Despite the striking chromosomal variability within Microtus, phenotypic variation is unremarkable. To determine whether nucleotide substitution rates are also elevated in voles, we sequenced the entire mitochondrial DNA (mtDNA) genome of the Eurasian sibling vole (Microtus rossiaemeridionalis). We compared this genome to another previously sequenced vole mtDNA genome (Microtus kikuchii) and performed pairwise sequence comparisons with the mtDNA genomes of ten additional mammalian genera. We found that microtine mtDNA genomes are evolving more rapidly than any other mammalian lineage we sampled, as gauged by the rate of nucleotide substitution across the entire mtDNA genome as well as at each individual protein-coding gene. Additionally, we compared substitution rates within the cytochrome b gene to seven other rodent genera and found that Microtus mtDNA is evolving fastest. The root cause of accelerated evolution in Microtus remains uncertain, but merits further investigation.

  1. Rattus norvegicus (Rodentia: Muridae Infected by Leishmania (Leishmania infantum (syn. Le. chagasi in Brazil

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    Fabiana de Oliveira Lara-Silva

    2014-01-01

    Full Text Available In the present study we surveyed the fauna of phlebotomine sand flies and small mammals in peridomestic areas from a Brazilian municipality where the American cutaneous leishmaniasis (ACL is endemic. A total of 608 female phlebotomine sand flies were captured during nine months in 2009 and 2010. Seven different species were represented with 60% of them being Lutzomyia intermedia and Lu. whitmani, both incriminated vectors of ACL. Lu. longipalpis, a proven vector of visceral leishmaniasis (VL was also captured at high proportion (12.8%. Genomic DNA analysis of 136 species-specific pools of female sand flies followed by molecular genotyping showed the presence of Leishmania infantum DNA in two pools of Lu. longipalpis. The same Leishmania species was found in one blood sample from Rattus norvegicus among 119 blood and tissue samples analysed. This is the first report of Le. infantum in R. norvegicus in the Americas and suggests a possible role for this rodent species in the zoonotic cycle of VL. Our study coincided with the reemergence of VL in Governador Valadares.

  2. Are ribosomal DNA clusters rearrangement hotspots? A case study in the genus Mus (Rodentia, Muridae

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    Douzery Emmanuel JP

    2011-05-01

    Full Text Available Abstract Background Recent advances in comparative genomics have considerably improved our knowledge of the evolution of mammalian karyotype architecture. One of the breakthroughs was the preferential localization of evolutionary breakpoints in regions enriched in repetitive sequences (segmental duplications, telomeres and centromeres. In this context, we investigated the contribution of ribosomal genes to genome reshuffling since they are generally located in pericentromeric or subtelomeric regions, and form repeat clusters on different chromosomes. The target model was the genus Mus which exhibits a high rate of karyotypic change, a large fraction of which involves centromeres. Results The chromosomal distribution of rDNA clusters was determined by in situ hybridization of mouse probes in 19 species. Using a molecular-based reference tree, the phylogenetic distribution of clusters within the genus was reconstructed, and the temporal association between rDNA clusters, breakpoints and centromeres was tested by maximum likelihood analyses. Our results highlighted the following features of rDNA cluster dynamics in the genus Mus: i rDNA clusters showed extensive diversity in number between species and an almost exclusive pericentromeric location, ii a strong association between rDNA sites and centromeres was retrieved which may be related to their shared constraint of concerted evolution, iii 24% of the observed breakpoints mapped near an rDNA cluster, and iv a substantial rate of rDNA cluster change (insertion, deletion also occurred in the absence of chromosomal rearrangements. Conclusions This study on the dynamics of rDNA clusters within the genus Mus has revealed a strong evolutionary relationship between rDNA clusters and centromeres. Both of these genomic structures coincide with breakpoints in the genus Mus, suggesting that the accumulation of a large number of repeats in the centromeric region may contribute to the high level of chromosome repatterning observed in this group. However, the elevated rate of rDNA change observed in the chromosomally invariant clade indicates that the presence of these sequences is insufficient to lead to genome instability. In agreement with recent studies, these results suggest that additional factors such as modifications of the epigenetic state of DNA may be required to trigger evolutionary plasticity.

  3. Another one bites the dust: bite force and ecology in three caviomorph rodents (Rodentia, Hystricognathi).

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    Becerra, Federico; Echeverría, Alejandra Isabel; Casinos, Adrià; Vassallo, Aldo Iván

    2014-04-01

    Mammals have developed sophisticated strategies adapting to particular locomotor modes, feeding habits, and social interactions. Many rodent species have acquired a fossorial, semi-fossorial, or even subterranean life-style, converging on morphological, anatomical, and ecological features but diverging in the final arrangement. These ecological variations partially depend on the functional morphology of their digging tools. Muscular and mechanical features (e.g., lever arms relationship) of the bite force were analyzed in three caviomorph rodents with similar body size but different habits and ecological demands of the jaws. In vivo forces were measured at incisors' tip using a strain gauge load cell force transducer whereas theoretical maximal performance values, mechanical advantages, and particular contribution of each adductor muscle were estimated from dissections in specimens of Ctenomys australis (subterranean, solitary), Octodon degus (semi-fossorial, social), and Chinchilla laniger (ground-dweller, colonial). Our results showed that C. australis bites stronger than expected given its small size and C. laniger exhibited the opposite outcome, while O. degus is close to the expected value based on mammalian bite force versus body mass regressions; what might be associated to the chisel-tooth digging behavior and social interactions. Our key finding was that no matter how diverse these rodents' skulls were, no difference was found in the mechanical advantage of the main adductor muscles. Therefore, interspecific differences in the bite force might be primarily due to differences in the muscular development and force, as shown for the subterranean, solitary and territorial C. australis versus the more gracile, ground-dweller, and colonial C. laniger.

  4. Early evolutionary differentiation of morphological variation in the mandible of South American caviomorph rodents (Rodentia, Caviomorpha).

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    Alvarez, A; Perez, S I; Verzi, D H

    2011-12-01

    Caviomorphs are a clade of South American rodents recorded at least since the early Oligocene (> 31.5 Ma) that exhibit ample eco-morphological variation. It has been proposed that phylogenetic structure is more important than ecological factors for understanding mandibular shape variation in this clade. This was interpreted as a result of the long-standing evolutionary history of caviomorphs and the early divergence of major lineages. In this work, we test this hypothesis through the analysis of morphological variation in the mandible of living and extinct species and compare this information with that obtained through comparative phylogenetic analyses. Our results support the hypothesis of early origin of mandibular variation; moreover, they suggest the conservation of early differentiated morphologies, which could indicate the existence of constrained evolutionary diversification.

  5. Scaling and adaptations of incisors and cheek teeth in caviomorph rodents (Rodentia, Hystricognathi).

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    Becerra, Federico; Vassallo, Aldo I; Echeverría, Alejandra I; Casinos, Adrià

    2012-10-01

    The South American hystricognath rodents are one of the most diverse mammalian clades considering their occupied habitats, locomotor modes and body sizes. This might have been partly evolved by diversification of their masticatory apparatus' structure and its ecological commitment, for example, chisel-tooth digging. In this phylogeny-based comparative study, we test the relationship between ecological behavior and mechanical features of their incisors and molariforms. In 33 species of nine families of caviomorph rodents, we analyze incisor attributes related to structural stress resistance and molar features related with grinding capacity, for example, second moment of inertia and enamel index (EI) (enamel band length/occlusal surface area), respectively. Most of these variables scaled isometrically to body mass, with a strong phylogenetic effect. A principal component analysis discrimination on the EI clustered the species according to their geographic distribution. We presume that selective pressures in Andean-Patagonian regions, on particular feeding habits and chisel-tooth digging behaviors, have modeled the morphological characteristics of the teeth. Subterranean/burrower ctenomyids, coruros, and plains viscachas showed the highest bending/torsion strength and anchorage values for incisors; a simplified enamel pattern in molariforms would be associated with a better grinding of the more abrasive vegetation present in more open and drier biomes.

  6. Two new species of Hymenolepis (Cestoda: Hymenolepididae) from murid rodents (Rodentia: Muridae) in the Philippines.

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    Makarikov, Arseny A; Tkach, Vasyl V; Bush, Sarah E

    2013-10-01

    Two previously unrecognized species of the genus Hymenolepis are described based on specimens obtained from murid rodent species Bullimus luzonicus , Apomys microdon , and Rattus everetti collected on Luzon Island, Philippines. Hymenolepis bicauda n. sp. differs from all known Hymenolepis spp. in relative position of the poral dorsal and ventral osmoregulatory canals, gravid uterus occupying less than half the length of proglottid, relatively few eggs, and the highly characteristic longitudinal split of proglottids at the end of the gravid strobila. Hymenolepis haukisalmii n. sp. differs from all known Hymenolepis spp. in the relative position of both poral and aporal dorsal and ventral osmoregulatory canals and uterus lacking dorsal and ventral diverticula. The shift in the relative position of the dorsal and ventral osmoregulatory canals was not known in Hymenolepis from rodents in other regions of the world and is reminiscent of the situation observed in Hymenolepis erinacei, parasitic in hedgehogs, and members of the genus Talpolepis, parasitic in moles. The cosmopolitan species Hymenolepis diminuta was the only member of the genus previously reported from the Philippines.

  7. Helminthes of synanthropic rodents (Rodentia: Muridae) from Dakahlia and Menoufia, Egypt.

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    Elshazly, Atef M; Awad, Soha I; Azab, Manar S; Elsheikha, Hany M; Abdel-Gawad, Abdel Gawad E; Khalil, Hazem H M; Morsy, Tosson A

    2008-12-01

    A cross-sectional survey was conducted to monitor and compare the prevalence of helminthes in rodents from Dakahlia and Menoufia governorates. The domestic rodents (271) were Rattus norvegicus, Rattus rattus frugivorous, Rattus r. alexandrinus, & Mus musculus. The overall prevalence of helminthes was 52.8%. In Dakahlia, 72/145 rats (49.6%) were infected. The highest prevalence of infection was in R. r. frugivorous 43 (60.4%), then R. r. alexandrinus 44 (47.7%), R. norvegicus 38 (44.7%), and the lowest was M. musculus 20 (40%). In Menoufia, 71/126 rats (56.3%) were infected. The highest prevalence of infection was in R. r. frugivorous 36 (77.7%), then M. musculus 27 (48.1%), R. norvegicus 23 (47.8%), and the lowest was in R. r. alexandrinus 40 (47.5%). A total of 24 species of helminthes (11 trematodes, 4 cestodes & 10 nematodes) were identified among the 271 rodents. The commonest trematode was Mesostephanus aegypticus followed by Stictodora tridactyla. The commonest cestode was Hymenolepis diminuta followed by Taenia taeniaformis. The commonest nematode was Capillaria hepatica followed by Trichurus muris. Given the zoonotic potential of rodents' parasites and since several residential, commercial, and agricultural sites exist in the examined geographic areas, the potential health risk should not be ignored.

  8. On the systematic position of the Western Hamster, Cricetus cricetus canescens Nehring (Mammalia: Rodentia)

    NARCIS (Netherlands)

    Husson, A.M.

    1959-01-01

    The systematic position of the western hamster, Cricetus cricetus canescens, has been a subject of discussion and criticism ever since NEHRING (1899, pp. 1—2) described the hamster occurring in Belgium west of the Meuse as a separate variety. The present paper is a new effort to throw more light on

  9. Entwicklungsstufen der miozänen Cricetodontinae (Mammalia, Rodentia) Mittelspaniens und ihre stratigraphische Bedeutung

    NARCIS (Netherlands)

    Freudenthal, M.

    1963-01-01

    During the summer holidays of 1960 to 1963 a great many localities of Miocene and Pliocene mammals were discovered in the Southern part of Zaragoza province (Spain). Remains of both large and small mammals were found, the latter by sieving clays and marls. This small fauna consists mainly of Criceto

  10. Landscape ecology of Trypanosoma cruzi in the southern Yucatan Peninsula.

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    López-Cancino, Sury Antonio; Tun-Ku, Ezequiel; De la Cruz-Felix, Himmler Keynes; Ibarra-Cerdeña, Carlos Napoleón; Izeta-Alberdi, Amaia; Pech-May, Angélica; Mazariegos-Hidalgo, Carlos Jesús; Valdez-Tah, Alba; Ramsey, Janine M

    2015-11-01

    Landscape interactions of Trypanosoma cruzi (Tc) with Triatoma dimidiata (Td) depend on the presence and relative abundance of mammal hosts. This study analyzed a landscape adjacent to the Calakmul Biosphere Reserve, composed of conserved areas, crop and farming areas, and the human community of Zoh Laguna with reported Chagas disease cases. Sylvatic mammals of the Chiroptera, Rodentia, and Marsupialia orders were captured, and livestock and pets were sampled along with T. dimidiata in all habitats. Infection by T. cruzi was analyzed using mtDNA markers, while lineage and DTU was analyzed using the mini-exon. 303 sylvatic specimens were collected, corresponding to 19 species during the rainy season and 114 specimens of 18 species during dry season. Five bats Artibeus jamaicensis, Artibeus lituratus, Sturnira lilium, Sturnira ludovici, Dermanura phaeotis (Dp) and one rodent Heteromys gaumeri were collected in the three habitats. All but Dp, and including Carollia brevicauda and Myotis keaysi, were infected with predominately TcI in the sylvatic habitat and TcII in the ecotone. Sigmodon hispidus was the rodent with the highest prevalence of infection by T. cruzi I and II in ecotone and domestic habitats. Didelphis viginiana was infected only with TcI in both domestic and sylvatic habitats; the only two genotyped human cases were TcII. Two main clades of T. cruzi, lineages I (DTU Ia) and II (DTU VI), were found to be sympatric (all habitats and seasons) in the Zoh-Laguna landscape, suggesting that no species-specific interactions occur between the parasite and any mammal host, in any habitat. We have also found mixed infections of the two principal T. cruzi clades in individuals across modified habitats, particularly in livestock and pets, and in both haplogroups of T. dimidiata. Results are contradictory to the dilution hypothesis, although we did find that most resilient species had an important role as T. cruzi hosts. Our study detected some complex trends in

  11. Comportamiento social y reproductivo del roedor subterráneo solitario Ctenomys talarum (Rodentia: Ctenomyidae en condiciones de semicautiverio Social and reproductive behavior of the subterranean solitary rodent Ctenomys talarum (Rodentia: Ctenomyidae in a seminatural enclosure

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    ROXANA R. ZENUTO

    2002-03-01

    Full Text Available Se estudió el comportamiento social y reproductivo en grupos de individuos del roedor subterráneo Ctenomys talarum (Thomas, 1898 en condiciones seminaturales, que reflejaron la complejidad de las cuevas de la especie así como también la relación de sexos típica de poblaciones naturales. Los datos sugieren que las interacciones entre los individuos son mucho más variadas y complejas que lo esperado para una especie solitaria y territorial. Diferentes canales de comunicación _auditivo, táctil y olfativo- fueron importantes para el establecimiento y mantenimiento de territorios y durante el cortejo y la cópula. Se observaron diferencias en el comportamiento social entre individuos de poblaciones naturales con diferentes características ecológicas. Individuos pertenecientes a la población de Mar de Cobo, que presenta una alta densidad y una proporción de sexos desviada a favor de las hembras, establecieron jerarquías de dominancia entre los machos, lo que determinó el acceso preferencial por parte del macho dominante a varias hembras. La observación de daño físico (heridas fue común entre machos de la población de Mar de Cobo. En contraste, la agresión entre machos de la población de Necochea, que presenta una baja densidad y una proporción de sexos balanceada, usualmente no resultó en daño físico y no se detectó una jerarquía de dominancia; los machos cortejaron a las hembras aún en presencia de otros machosThe social and reproductive behavior of the subterranean rodent Ctenomys talarum (Thomas, 1898 was studied in a seminatural enclosure resembling both the complexity of the natural burrow system and the sex ratio observed in wild populations. Contrary to expectations based on their solitariness and their rather simple social system, the interactions among individuals of this species were diverse and complex. Auditory, tactile and chemical communication were of importance during territory guarding, courtship and copulatory behavior. Individuals from different populations differing in ecological attributes behaved in substantially different ways. Males from Mar de Cobo, a population characterized by a high density and a skewed sex ratio favouring females, behaved aggressively, which resulted in frequent wounding. Males from Mar de Cobo established a dominance hierarchy among them, which preceded courtship and, eventually, resulted in the dominant male monopolizing mating activity. On the contrary, males from Necochea, a population showing low density and an even sex ratio, behaved less aggressively; dominance relationships were absent, and males performed courtship behaviors in the presence of other males

  12. Dustbathing and intra-sexual communication of social degus, Octodon degus (Rodentia:Octodontidae Baños de tierra y comunicación intra-sexual en el degu social, Octodon degus (Rodentia: Octodontidae

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    LUIS A. EBENSPERGER

    2000-06-01

    Full Text Available I observed the behavior of captive male and female Octodon degus to assess if dustbathing behavior plays a role in social communication among unfamiliar, same-sex conspecifics. Degus of a first group (control responders were individually exposed during 10-min tests to an arena containing loose, clean soil. I compared the latency to first dustbathing as well as the overall frequency of dustbathing events recorded to control responders with the corresponding figures recorded to a second group of degus (experimental responders after they were individually introduced into the same arena but with soil previously used for dustbathing by a same-sex conspecific (depositor. I also compared the location of dustbathing events by experimental responders with that of depositor individuals. Although male degus tended to exhibit shorter latencies to first dustbathing event when in clean soil, this variable was not significantly influenced by sex of responders or the type of soil (clean or used. In contrast, a significant interaction between both factors revealed that males dustbathe at a higher rate than females when on clean soil, but similarly so when in a substratum previously dustbathed by a same-sex conspecific. The place chosen by both male and female responders to conduct their dustbathing behavior was unrelated to the presence of previous marks left by a depositor degu. I conclude that dustbathing is involved in communication during male-male, but not during female-female, interactions in the degu. I suggest that such male-male interactions represent competition for matesObservé el comportamiento de machos y hembras en cautiverio del roedor social Octodon degus para evaluar si la conducta de bañarse en tierra es parte de un mecanismo de comunicación social entre conespecíficos del mismo sexo, desconocidos entre sí. Un primer grupo de degus (respondientes controles fueron introducidos individualmente durante ensayos de 10 min a un terrario con tierra suelta y limpia (no usada previamente por otros degus. Comparé el tiempo transcurrido desde el inicio de cada experimento hasta la observación del primer baño de tierra (latencia así como el número total de baños de tierra realizados por cada respondiente control, con los valores equivalentes obtenidos de un segundo grupo de degus (respondientes experimentales, observados en la misma arena pero con tierra usada previamente por un conespecífico del mismo sexo (depositante. También comparé la ubicación espacial de los baños de tierra efectuados por respondientes experimentales con la posición de los baños de tierra realizados previamente por degus depositantes. Aunque los respondientes macho tendieron a mostrar una latencia más corta, esta variable no fue afectada significativamente ni por el sexo de los respondientes ni por el tipo de sustrato (limpio o usado. En cambio, una interacción significativa entre ambos factores mostró que los respondientes macho efectuaron un mayor número de baños de tierra que las hembras cuando ambos fueron expuestos a un sustrato limpio, pero que tales diferencias desaparecen cuando los individuos son expuestos a un sustrato usado previamente por otro individuo del mismo sexo. Los sitios de la arena seleccionados por respondientes macho y hembra para efectuar sus baños de tierra no estuvieron relacionados con la presencia de marcas dejadas por degus depositantes. Concluyo que los baños de tierra son usados por el degu como un mecanismo de comunicación olfativa durante interacciones entre machos, pero no entre hembras. Sugiero que tales interacciones entre machos representan competencia por apareamientos

  13. Dieta de Sciurus ingrami Thomas (Rodentia, Sciuridae em um remanescente de Floresta com Araucária, Paraná, Brasil Diet of Sciurus ingrami Thomas (Rodentia, Sciuridae on a Araucauria Pine Forest remnant, Paraná, Brazil

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    João M. D. Miranda

    2005-12-01

    Full Text Available Este estudo foi realizado entre fevereiro de 2002 e janeiro de 2003, em um remanescente de Floresta com Araucária, localizado no Distrito do Bugre, Município de Balsa Nova, Paraná, Brasil. O objetivo foi conhecer as espécies utilizadas na alimentação por Sciurus ingrami Thomas, 1901 no decorrer de um ano. Foram registradas dez (N = 10 espécies na dieta dos serelepes, pertencentes a sete famílias botânicas. Os serelepes predaram sementes de três espécies e se alimentaram de três espécies exóticas, mostrando adaptabilidade a ambientes alterados.This study was conducted between February, 2002 and January, 2003 in a remnant of Araucaria Pine Forest located in the District of Bugre, Municipality of Balsa Nova, Paraná, Brazil. The goal of this study was to survey the species used as food items by Sciurus ingrami Thomas, 1901 throughout a year. Ten (N = 10 species were recorded in the diet of these squirrels, belonging to seven plant families. Squirrels preyed on seeds of three plant species and fed on three exotic species, indicating good adaptability to disturbed habitats.

  14. Formas de abertura dos frutos de Syagrus romanzoffiana (Chamisso glassman efetuadas por Sciurus ingrami Thomas (Rodentia, Sciuridae Opening forms of palm nuts Syagrus romanzoffiana (Chamisso Glassman made by Sciurus ingrami Thomas (Rodentia, Sciuridae

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    Marcelo Bordignon

    1996-01-01

    Full Text Available In this work was identifyed the diferents opening forms of the palm nuts Syagrus romanzoffiana by brazilian squirrel Sciurus ingrami in four diferents points of Curitiba, Paraná, Brazil. Was caracterized tive basic forms of opening, in acording with the number of incisions and opening aspects. The form with lower number of incisions (two was also the greather frequently in the four points sampled (66,25%; N = 5194 well as registred the lower opening time (7,2 ± 1,7 min in relationship with other forms (9,2 ± 2,3 min. To explicate the diferences in the frequences of forms discovered, is proposed "apprenticeship's hypothesis" which the young squirrels of the population, along the opening nuts apprenticeship, to passing of the forms with larger number of incisions to forms with lower number of incisions, ending in the form of more frequence, which is maintained by adult squirrels.

  15. Habitat use and relative abundance of the Spotted Paca Cuniculus paca (Linnaeus, 1766 (Rodentia: Cuniculidae and the Red-rumped Agouti Dasyprocta leporina (Linnaeus, 1758 (Rodentia: Dasyproctidae in Guatopo National Park, Venezuela

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    Elinor Jax

    2015-01-01

    Full Text Available The Spotted Paca Cuniculus paca and the Red-rumped Agouti Dasyprocta leporina are affected by habitat loss and hunting.  In Venezuela, their conservation status is unknown, even within protected areas.  The objective of this study was to estimate the relative abundance, activity patterns, habitat use, and effect of human activities on these species in Venezuela.  To achieve this, 26 camera-trap stations (20.8km2 were established in Guatopo National Park between February and April 2011, characterization of the habitat was undertaken and occupancy models were created.  The relative abundance of the Spotted Paca was 1.62 captures/100trap-nights, with a fully nocturnal activity pattern.  The relative abundance of the Red-rumped Agouti was 2.32 captures/100trap-nights, with a pronounced diurnal activity pattern. The occupation probability of the Red-rumped Agouti (0.61 SE 0.02 was higher than that of the Spotted Paca (0.27 SE 0.02. Spotted Pacas were mainly found in areas with mature forest and high tree density, whereas the  Red-rumped Agoutis were most frequently found in valleys with little disturbed forest.  A positive correlation was found between illegal hunting activities and areas occupied by the Spotted Paca.  It is important to strengthen the park control measurements to reduce illegal hunting of Spotted Pacas.

  16. Estudio sistemático y bioestratigráfico de los Eomyidae (Rodentia) del Oligoceno superior y Mioceno inferior español = Taxonomy and biostratigraphy of Eomyidae (Rodentia) from the upper Oligocene and lower Miocene of Spain

    NARCIS (Netherlands)

    Alvarez Sierra, M.A.

    1987-01-01

    This paper is the first fundamental study on Spanish Eomyidae. The flourishing time of this family in Europe was the Late Oligocene and Early Miocene. Four genera are recognized in this time span: Rhodanomys Depéret & Douxami, 1902, Ritteneria Stehlin & Schaub, 1951, Pseudotheridomys Schlosser, 1926

  17. PATRONES DE REPLICACIÓN Y BANDEO NO DIFERENCIAL EN ARDILLAS COLOMBIANAS DEL GÉNERO Sciurus (RODENTIA, SCIURIDAE Replication Patterns and no Differential Banding in Colombian Squirrels, Sciurus (Rodentia, Sciuridae

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    CAROLINA ARANGO

    2012-05-01

    Full Text Available Las ardillas colombianas muestran una gran variabilidad citogenética lo que ha despertado el interés en ahondar aspectos evolutivos en el grupo. Para esto, varias herramientas de bandeo cromosómico convencional como bandas diferenciales Q y R y bandas no diferenciales C y NOR fueron analizadas permitiendo, por primera vez en las ardillas colombianas, detectar señales de cromosómicas inusuales de replicación e inactivación de heterocromatina y cromosomas marcadores específicos. Se explica la utilidad de cada uno de estos complementos en el análisis citogenético de especies y las observaciones para los citotipos de las ardillas colombianas.Colombian Squirrels cytogenetics showed a great variability which has renewed the interest in evolutionary aspects within the group. Many chromosome banding tools must be analyzed carefully in addition to the classical G-banding G technique. These techniques include other differential bands like Q and R banding and nondifferential banding (C and NOR. In this article the use of each of these supplements in the cytogenetic analysis of species and cytotypes observations for the Colombian squirrels is explained.

  18. Ritmos de actividad locomotora y uso de las cuevas en condiciones seminaturales en Ctenomys talarum (Rodentia, Octodontidae Rhythms of locomotor activity and burrow use under seminatural conditions in Ctenomys talarum (Rodentia, Octodontidae

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    FACUNDO LUNA

    2000-03-01

    Full Text Available Ctenomys es un género de roedores subterráneos que vive en sistemas de galerías cerrados a la superficie del suelo y por lo tanto lleva a cabo la mayoría de sus actividades en ausencia de luz. Sin embargo a diferencia de otros roedores subterráneos sus salidas a la superficie son frecuentes. En este trabajo fueron evaluadas, en Ctenomys talarum (Thomas, 1898 la existencia y las características de los ritmos locomotores de actividad para distintas condiciones experimentales. Además, fueron analizadas la permanencia y preferencia por distintos sectores del sistema de galerías. El 25 % de los individuos de C. talarum analizados, para las distintas condiciones de fotoperiodo y temperatura ambiente evaluadas, mostraron actividad rítmica. Por otra parte, los individuos no presentaron un patrón generalizado de permanencia y preferencia por sectores definidos en el sistema de galeríasCtenomys are subterranean rodents that perform most of their daily activities in dark, thermally stable burrow systems. In this paper the dependence of Ctenomys talarum (Thomas, 1898 activity rhythms on either photoperiod and ambient temperature was analyzed, as well as permanency and preference for different sectors of a burrow system. 25 % of the individuals showed rhythmicity in their activities. Thus, luminous stimuli and ambient temperature did not affect activity pattern in this species. Furthermore, individuals of C. talarum did not show any generalized pattern of preference and permanency on defined sectors of the artificial burrow system

  19. MYOCASTOR COYPUS (“COIPO”, RODENTIA, MAMMALIA COMO RECURSO EN LOS HUMEDALES DE LA PAMPA BOANERENSE: PATRONES DE EXPLOTACIÓN/Myocastor coypus (“coipo”, Rodentia, Mammalia as an archaeological resource in the wetlands of Buenos Aires Pampas: exploitation

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    Paula Escosteguy

    2012-11-01

    Full Text Available Myocastor coypus es una de las especies más abundantes en los humedales de la región pampeana, particularmente en las cuencas de los ríos Salado y Paraná. Distintas líneas de evidencia permiten sostener que fue un recurso ampliamente aprovechado siendo central en las estrategias económicas de los cazadores-recolectores-pescadores durante el Holoceno tardío. Se presentan los resultados obtenidos del análisis de restos arqueofaunísticos de esta presa mediano-pequeña, a partir de: análisis cuantitativos, estimación de clases de edad, análisis de huellas, termoalteraciones y fracturas. El objetivo es analizar los patrones de explotación del coipo utilizando información proveniente de los sitios de la localidad La Guillerma (LG1, LG4 y LG5 y San Ramón 7 (SR7 ubicados en el curso inferior del río Salado y del sitio Río Luján (RL y la localidad Cañada Honda (CH localizados en el NE bonaerense. Los resultados permiten sostener que la presión de captura se dio sobre presas adultas, que ingresaron completas a los sitios. Las huellas evidencian la ejecución de una serie de acciones para su aprovechamiento (cuereo, desarticulación y descarne. Abstract Myocastor coypus is one of the most abundant species found in archaeological sites in the Pampean Region wetlands, especially in the Salado and Paraná river basins. On the basis of different lines of evidence, it may be suggested that this animal was an extensively exploited resource, proving to be central in the strategies of hunter-gatherer-fishers that inhabited these regions during the Late Holocene. In this study, data obtained from archaeofaunal analysis are described: quantitative, age-class and butchering evidence analysis (cut marks, burning features and fracture patterns. We aim at analyzing the exploitation patterns of coypu using data found in La Guillerma (LG1, LG4 and LG5 and San Ramón 7 (SR7, pertaining to the lower Río Salado basin, and in Río Luján (RL and Cañada Honda (CH situated in the northeastern province of Buenos Aires. Results show that adult prey capture was practised, where the entire animal bodies had been introduced in the sites. Cut marks also evidence a series of tasks associated to exploitation (skinning, disarticulation and defleshing.

  20. Aprovechamiento de Myocastor coypus (Rodentia, Caviomorpha en sitios del Chaco Húmedo argentino durante el Holoceno tardío Myocastor coypus (Rodentia, Caviomorpha procurement at sites in the argentinean Chaco Humedo during the late Holecene

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    Mariano Santini

    2011-07-01

    Full Text Available De los mamíferos presentes en los sitios arqueológicos del Chaco Húmedo durante el Holoceno tardío, Myocastor coypus constituyó un recurso importante en la subsistencia de los grupos humanos que habitaron la zona de esteros, cañadas y selvas de ribera. El objetivo de este trabajo es presentar los resultados obtenidos del estudio de los materiales arqueofaunísticos correspondientes a M. coypus provenientes de los sitios El Cachapé Potrero V y Sotelo 1 (departamento Primero de Mayo, provincia del Chaco. Cronológicamente, estos sitios se sitúan entre los 1200 y 1690 años AP. Los materiales analizados ascienden a un NISP de 7868 y 4412 y un MNI de 251 y 259, para Potrero V y Sotelo 1, respectivamente, y representan el 84% y 77,1% del total de especímenes recuperados. Además del análisis cuantitativo se determinaron los perfiles etarios y se analizaron las modificaciones óseas, antrópicas y naturales, que permitieron identificar los agentes tafonómicos que intervinieron en la formación de los conjuntos muestreados. Los estudios mostraron que se realizó un aprovechamiento integral del coypo -al cual se lo utilizó tanto como fuente de alimento como de materia prima para la confección de instrumentos óseos-; y que, probablemente, también se haya aprovechado su cuero.Of the mammals from archaeological sites in Chaco Province, Myocastor coypus constituted an important subsistence resource for the human groups that inhabited the area of Esteros, Cañadas and Selvas de Ribera in the Late Holocene. The aim of this paper is to present the results of materials studies relating to M. coypus from the archaeological sites of El Cachapé Potrero 5 and Sotelo 1 (Primero de Mayo Department, Chaco Province. Chronologically, these sites are located between 1200 and 1690 years BP. The NISP was 7,868 and 4,412 and the MNI 251 and 259 for Potrero V and Sotelo I, respectively, accounting for 84% and 77.1% of all specimens recovered from the two archaeological sites. In addition to quantitative analysis, age profiles and osseous, anthropogenic, and natural modifications were analyzed, identifying the various taphonomic agents that influenced the formation of the samples. M. coypus was of great importance to the subsistence of human groups that inhabited the region. Such groups took full advantage of the rodent, using them not only as a food resource but also as a raw material for the manufacture of bone tools and probably also for their hides.

  1. A new Appenninic station of Dryomys nitedula Pallas, 1979 (Rodentia, Gliridae / Nuova stazione appenninica di Dryomys nitedula (Pallas, 1779 (Rodentia, Gliridae

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    Maria Grazia Filippucci

    1986-06-01

    Full Text Available Abstract A new record of Dryomys nitedula from the massif of Pollino (Southern Italy is given and the value of the subspecific division (D. nitedula intermedius, D. nitedula aspromontis in Italy is discussed. Riassunto Viene segnalato il ritrovamento di un esemplare di Dryomys nitedula sul Massiccio del Pollino e ridiscusso il valore della ripartizione sottospecifica (D. nitedula intermedius, D. nitedula aspromontis in Italia.

  2. Dietas de Abrothrix andinus, Phyllotis xanthopygus (Rodentia y Lepus europaeus (Lagomorpha en un ambiente altoandino de Chile Feeding habits of Abrothrix andinus, Phyllotis xanthopygus (Rodentia and Lepus europaeus (Lagomorpha in an Andean environment of Chile

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    FRANCISCO LÓPEZ-CORTÉS

    2007-03-01

    Full Text Available Los roedores nativos Abrothrix andinus, Phyllotis xanthopygus y el lagomorfo introducido Lepus europaeus, coexisten en ambientes altoandinos del centro-norte de Chile, donde la disponibilidad de alimento es escasa y distribuida heterogéneamente en el paisaje. Propusimos que en estos ambientes las especies en estudio se comportarían como herbívoros generalistas y que existiría una alta sobreposición en la dieta entre la liebre y los roedores nativos. El objetivo de este trabajo fue documentar la composición de la dieta de las tres especies y determinar su amplitud, preferencia y sobreposición en la dieta a partir del análisis microhistológico de heces frescas. Los resultados indican que las tres especies se comportaron como herbívoros-folívoros, siendo la dieta de L. europaeus la de mayor amplitud trófica. Abrothrix andinus seleccionó todos los ítemes que consume, mientras que P. xanthopygus y L. europaeus realizaron un consumo más oportunista. La mayor sobreposición en la dieta se observó entre los roedores nativosThe native rodents Abrothrix andinus, Phyllotis xanthopygus and the introduced lagomorph Lepus europaeus coexist in the highlands of north-central Chile, where food availability is scarce. We hypothesized that in these environments, the studied species would behave as generalist herbivores and where the diet of native rodents would overlap that of hares greatly. The aim of this study was to quantify feeding habits, amplitude, diet preferences and overlap of these three species through microhistological analysis of fresh faeces. While all three species behaved as herbivore-folivores, L. europaeus showed the largest niche breath. Abrothrix andinus selected all consumed items, while P. xanthopygus and L. europaeus exhibited a more opportunistic consumption food items. The highest diet overlap was observed between native rodents

  3. Temporal dynamics of milk composition of the precocial caviomorph Octodon degus (Rodentia: Octodontidae) Dinámica temporal de la composición de la leche del caviomorfo precocial Octodon degus (Rodentia: Octodentidae)

    OpenAIRE

    CLAUDIO VELOSO; G.J. KENAGY

    2005-01-01

    During lactation, both the nutritional and energetic requirements of suckling change gradually. These changes normally are accompanied by modifications in chemical composition of the milk. We investigated the temporal course of milk composition during lactation in a precocial caviomorph rodent, the "degu" (Octodon degus) under laboratory condition. Female degus were kept in laboratory during gestation and lactation and fed with commercial food pellets. Milk was collected at three stages of la...

  4. Dustbathing and intra-sexual communication of social degus, Octodon degus (Rodentia:Octodontidae) Baños de tierra y comunicación intra-sexual en el degu social, Octodon degus (Rodentia: Octodontidae)

    OpenAIRE

    Luis A. Ebensperger

    2000-01-01

    I observed the behavior of captive male and female Octodon degus to assess if dustbathing behavior plays a role in social communication among unfamiliar, same-sex conspecifics. Degus of a first group (control responders) were individually exposed during 10-min tests to an arena containing loose, clean soil. I compared the latency to first dustbathing as well as the overall frequency of dustbathing events recorded to control responders with the corresponding figures recorded to a second group ...

  5. Parâmetros hematológicos do roedor fossorial Ctenomys lami (Rodentia, Ctenomidae no estado do Rio Grande do Sul Hematological parameters of fossorial rodent Ctenomys lami (Rodentia, Ctenomidae in Rio Grande do Sul, Brazil

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    Gisele G. Stein

    2010-08-01

    Full Text Available O perfil hematológico sanguíneo foi determinado em três populações de Ctenomys lami, em áreas denominadas A e B, impactadas pela bovinocultura, e C, sem impacto antrópico, ambas no sul do Brasil. Sessenta e dois animais foram coletados ao total. Os valores de hematócrito (Ht, hemoglobina (Hb e eritrócitos apresentaram diferenças significativas entre machos e fêmeas. Os valores médios de Ht e a Hb encontrados na espécie foram mais baixos em comparação com os de outras espécies de roedores subterrâneos, podendo estes valores estarem relacionados ao habitat de forrageio ou às características do solo. Também foram encontradas diferenças significativas nas médias de hemoglobina, CHCM e linfócitos em animais das áreas A e B em relação à área C. O valor da média dos hematócritos dos animais entre as áreas foi mais elevado nas áreas A e B, porém significativamente diferentes entre A e C. Algumas dessas alterações sugerem a relação dos valores encontrados com o estresse dos animais em relação a áreas impactadas. Variações significativas no VCM foram encontradas entre os animais das áreas A e C, e também nas plaquetas destes entre as áreas A e B. Não foram observados Corpúsculo de Kurloff no sangue dos animais analisados. Os valores hematológicos encontrados nesses espécimes de Ctenomys lami fornecem informações importantes sobre a espécie e podem ser úteis em outras pesquisas.The hematological profile was determined in three populations of Ctenomys lami that inhabits three different areas nominated as A and B, affected by cattle production, and C, without human impact, all of them in southern Brazil, under the same geologic formation. Sixty two individuals were collected. The packed cell volume (PCV values, hemoglobin (Hb and red blood cell (RBC count presents statistic significant differences between males and females. PCV and Hb values were lower in comparison with other subterranean rodents, which could be related to the food searching behavior or soil characteristic of the species. Significant statistic differences were found to for Hb, mean corpuscular hemoglobin concentration (MCHC and lymphocytes between animals belonging to A and C areas. The PCV values were higher for animals from areas A and B, with significance only between A and C. Some of these alterations may suggest a modification on stress levels of the animals inhabiting areas A and B with anthropic alterations, or maybe just an inherited characteristic. Significant statistic differences were found either in mean corpuscular volume (MCV between A and C areas, and platelets between A and B areas. No Kurloff cells were observed in the blood smear from analyzed individuals. The hematological values founded for Ctenomys lami are an important information for this species, which can be used for future research and management.

  6. Molerats (Bathyergidae, Rodentia in South African National Parks: notes on the Taxonomic "isolation" and Hystricomorph Affinities of the family

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    G de Graaff

    1979-01-01

    Full Text Available The history of classification ofAfrotropical molerats is reviewed and an assessment is made of the supposed taxonomic "isolation" of the molerats (bathyergids by considering morphological features in the skull, post-cranial skeleton, reproductive organs and myology which collectively point to hystricomorph affinities in contrast to a myomorph relationship which is often postulated.

  7. Anatomia comparada e morfometria de oligoryzomys nigripes e o. flavescens (rodentia, sigmodontinae no Rio Grande do Sul, Brasil

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    Leonardo F. Machado

    2011-01-01

    Full Text Available Oligoryzomys nigripes e O. flavescens são amplamente distribuídos e simpátricos em diversos biomas. Os caracteres diagnósticos para seus reconhecimentos não são claramente estabelecidos. Neste estudo, foram realizadas a descrição e comparação da morfologia externa, anatomia do crânio, dentes, esqueleto pós crânio, morfologia estomacal e peniana. Análises estatísticas foram geradas a partir de dados morfométricos. A amostra consiste de 208 exemplares provenientes de 24 localidades do Brasil. O. nigripes é maior, com pelagem dorsal mais escura e pelagem ventral esbranquiçada e salpicada de preto. Crânio maior e mais robusto que O. flavescens. O. flavescens é menor, com pelagem dorsal levemente mais clara e ventre amarelado. O padrão de circulação cefálica das duas espécies é derivada de segundo tipo. Em O. flavescens são visualizados acidentes proeminentes na escápula e úmero, enquanto O. nigripes demonstrou maiores diferenças localizadas na crista íliaca, orientação do ísquio e acidentes proeminentes na tíbia e fíbula. A morfologia estomacal de ambos os táxons possui padrão Unilocular-hemiglandular. A morfologia do pênis consiste de báculo central tri-digitado. A análise de função discriminante reconhecem claramente a distinção de dois grupos homogêneos representados pelas espécies. Segundo o teste t duas variáveis morfométricas (largura da placa zigomática e largura do primeiro molar superior não são relevantes (P > 0.05 para a discriminação dos táxons. Dimorfismo sexual baseado na morfometria foi sustentado pelo teste t para O. nigripes. Em O. flavescens esta condição não é estatisticamente verificada.

  8. Comparative chromosome painting in six species of Oligoryzomys (Rodentia, Sigmodontinae and the karyotype evolution of the genus.

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    Camilla Bruno Di-Nizo

    Full Text Available Oligoryzomys belongs to the tribe Oryzomyini, and contains about 22 species. Diploid numbers range from 2n = 44 in Oligoryzomys sp. 2 to 2n = 72 in O. utiaritensis and phylogenetic relationships are not well defined. The high morphological convergence leads to misidentification of taxonomic entities and the species are often identified by chromosomal characters. Until now, the genus has been studied only by classical cytogenetic approaches. To understand the chromosomal evolution of Oligoryzomys, we developed chromosome probes from a female of Oligoryzomys moojeni (OMO with 2n = 70 and hybridized to other five Oligoryzomys species. The probes painted 31 segments on O. fornesi (OFO with 2n = 62; 32 segments on O. microtis (OMI, 2n = 64; 33 segments on O. nigripes (ONI, 2n = 62 and on O. rupestris (ORU, 2n = 46; and 34 on Oligoryzomys sp. 2 (OSP, 2n = 44. OMO probes 4 and 5 showed a syntenic association in O. fornesi, O. microtis and O. nigripes and were also presented in the same pair, although disrupted, in O. rupestris and Oligoryzomys sp. 2. Concerning O. rupestris and Oligoryzomys sp. 2, species with the lowest diploid numbers of the genus, a total of 8 probes hybridized to 11 segments on the largest pair of ORU 1 and 9 probes hybridized to 12 segments on OSP 1. Also, OMO 6 painted three segments in ORU, corresponding to the proximal segment of ORU 2q, and the whole of ORU 19 and 20. In OSP, the segment corresponding to ORU 20 was homologous to OSP 1p. OMO X showed signals of hybridization in both X and Y chromosomes. Extensive chromosomal rearrangements, that could not be detected by classical cytogenetic techniques, such as pericentric inversions or repositioning of centromeres, Robertsonian rearrangements and tandem fusions/fissions, as well as gain/activation or loss/inactivation of centromeres and telomeric sequences have driven the huge genome reshuffling in these closely related species.

  9. Karyotypic analyses and morphological comments on the endemic and endangered Brazilian painted tree rat Callistomys pictus (Rodentia, Echimyidae

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    Karen Ventura

    2008-01-01

    Full Text Available The genus Callistomys belongs to the rodent family Echimyidae, subfamily Echimyinae, and its only living representative is Callistomys pictus, a rare and vulnerable endemic species of the state of Bahia, Brazil. Callistomys has been previously classified as Nelomys, Loncheres, Isothrix and Echimys. In this paper we present the karyotype of Callistomys pictus, including CBG and GTG-banding patterns and silver staining of the nucleolus organizer regions (Ag-NORs. Comments on Callistomys pictus morphological traits and a compilation of Echimyinae chromosomal data are also included. Our analyses revealed that Callistomys can be recognized both by its distintinctive morphology and by its karyotype.

  10. Comparative chromosome painting in six species of Oligoryzomys (Rodentia, Sigmodontinae) and the karyotype evolution of the genus.

    Science.gov (United States)

    Di-Nizo, Camilla Bruno; Ventura, Karen; Ferguson-Smith, Malcolm Andrew; O'Brien, Patricia Caroline Mary; Yonenaga-Yassuda, Yatiyo; Silva, Maria José de J

    2015-01-01

    Oligoryzomys belongs to the tribe Oryzomyini, and contains about 22 species. Diploid numbers range from 2n = 44 in Oligoryzomys sp. 2 to 2n = 72 in O. utiaritensis and phylogenetic relationships are not well defined. The high morphological convergence leads to misidentification of taxonomic entities and the species are often identified by chromosomal characters. Until now, the genus has been studied only by classical cytogenetic approaches. To understand the chromosomal evolution of Oligoryzomys, we developed chromosome probes from a female of Oligoryzomys moojeni (OMO) with 2n = 70 and hybridized to other five Oligoryzomys species. The probes painted 31 segments on O. fornesi (OFO) with 2n = 62; 32 segments on O. microtis (OMI), 2n = 64; 33 segments on O. nigripes (ONI), 2n = 62 and on O. rupestris (ORU), 2n = 46; and 34 on Oligoryzomys sp. 2 (OSP), 2n = 44. OMO probes 4 and 5 showed a syntenic association in O. fornesi, O. microtis and O. nigripes and were also presented in the same pair, although disrupted, in O. rupestris and Oligoryzomys sp. 2. Concerning O. rupestris and Oligoryzomys sp. 2, species with the lowest diploid numbers of the genus, a total of 8 probes hybridized to 11 segments on the largest pair of ORU 1 and 9 probes hybridized to 12 segments on OSP 1. Also, OMO 6 painted three segments in ORU, corresponding to the proximal segment of ORU 2q, and the whole of ORU 19 and 20. In OSP, the segment corresponding to ORU 20 was homologous to OSP 1p. OMO X showed signals of hybridization in both X and Y chromosomes. Extensive chromosomal rearrangements, that could not be detected by classical cytogenetic techniques, such as pericentric inversions or repositioning of centromeres, Robertsonian rearrangements and tandem fusions/fissions, as well as gain/activation or loss/inactivation of centromeres and telomeric sequences have driven the huge genome reshuffling in these closely related species.

  11. Karyotypes of Akodon orophilus Osgood 1913 and Thomasomys sp. (Rodentia: Sigmodontinae from Huánuco, Peru

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    Víctor Pacheco

    2012-10-01

    Full Text Available Conventional chromosomal preparations were made of three native mice from Huánuco, Peru: a male and a female of Thomasomys sp., and a male of Akodon orophilus. Thomasomys sp. had a karyotype of 2n = 42, XY (n = 21, meanwhile A. orophilus presented 2n = 22, XY (n = 11. Comparisons between chromosomal pairs from the existent literature indicate that both are new karyotypes. Thomasomys sp. has a distinct sexual Y chromosome, the only metacentric (m reported for the genus. The chromosomes X and Y of A. orophilus are acrocentrics (a; and the length of chromosome Y (2/3 of the length of X distinguishes A. orophilus from other congeneric. Because the structural differences between the sexual chromosomes usually generates mechanism of reproductive isolation at intraspecific level and are bigger still in interspecific crosses, we concluded that the karyotypes reported here support the validity of the species A. orophilus and suggest that Thomasomys sp. represents a new species to science.

  12. Reproductive biology of the greater bandicoot rat Bandicota indica (Rodentia: Muridae) in the rice fields of southern Thailand

    Institute of Scientific and Technical Information of China (English)

    N.THITIPRAMOTE; J.SUWANJARAT; W.G.BREED

    2009-01-01

    This study investigated some aspects of the reproductive biology of male and female greater bandicoot rats,Bandicota indica,in southern Thailand from September 2004 to September 2006. In females,body,uterine and preputial gland weights,occurrences of pregnancies and placental scars,and in males,testicalar weights and histology,and sizes of accessory sex glands,were recorded. Pregnancies occurred predominantly,but not exclusively,in the wet season,with a higher incidence pregnancies in the second,than in the first,dry season. Uterine and preputial gland weights tended to be lower in the first,but not the second dry season,with placental scars occurring at all times of year. Males tended to have heavier testes in the wet season but some seminiferous tubules contained sperm even in the dry season. Seminal vesicles,but not prostates and preputial glands,tended to be heavier in animals in the wet season. We conclude that the greater bandieoot rat in southern Thailand shows maximal reproductive activity in the wet season with some reproductive activity,albeit variable from year to year,occurring in the dry season depending upon environmental conditions. This study has also shown that females,as well as males,have large preputial glands,and that males invariably have small testes regardless of the time of year. These observations suggest a similar timing of reproduction,but a different breeding biology and perhaps social organisation,from that of the sympatric ricefield rat,Rattus argentiventer.

  13. Reproductive biology of the greater bandicoot rat Bandicota indica (Rodentia: Muridae in the rice fields of southern Thailand

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    N. THITIPRAMOTE

    2009-02-01

    Full Text Available This study investigated some aspects of the reproductive biology of male and female greater bandicoot rats Bandicota indica in southern Thailand from September 2004 to September 2006. In females, body, uterine and preputial gland weights, occurrences of pregnancies and placental scars, and in males, testicular weights and histology, and sizes of accessory sex glands, were recorded. Pregnancies occurred predominantly, but not exclusively, in the wet season, with a higher incidence pregnancies in the second, than in the first, dry season. Uterine and preputial gland weights tended to be lower in the first, but not the second dry season, with placental scars occurring at all times of year. Males tended to have heavier testes in the wet season but some seminiferous tubules contained sperm even in the dry season. Seminal vesicles, but not prostates and preputial glands, tended to be heavier in animals in the wet season. We conclude that the greater bandicoot rat in southern Thailand shows maximal reproductive activity in the wet season with some reproductive activity, albeit variable from year to year, occurring in the dry season depending upon environmental conditions. This study has also shown that females, as well as males, have large preputial glands, and that males invariably have small testes regardless of the time of year. These observations suggest a similar timing of reproduction, but a different breeding biology and perhaps social organisation, from that of the sympatric ricefield rat, Rattus argentiventer [Current Zoology 55(1: 48–55, 2009].

  14. Association of the "IUCN vulnerable" spiny rat Clyomys bishopi (Rodentia: Echimyidae) with palm trees and armadillo burrows in southeastern Brazil.

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    Bueno, Adriana A; Lapenta, Marina J; Oliveira, Fátima; Motta-Junior, José C

    2004-12-01

    The globally vulnerable Clyomys bishopi, a semi-fossorial and colonial rodent, is apparently limited to cerrado (savannah-like vegetation) physiognomies in São Paulo State, Brazil. The aim of the study was to verify whether the presence of C. bishopi is associated to the occurrence of palm trees (Attalea gearensis, Syagrus loefgrenii) and armadillo burrows. Thirty six quadrats were placed in different physiognomies of cerrado vegetation at Itirapina Ecological Station, southeastern Brazil to survey the number of C. bishopi burrows of individuals of palm trees and burrows of armadillos. There was a strong dependence and association between the number of C. bishopi burrows and all measured variables (Contingency tables and Spearman rank correlations). It is suggested that this rodent can be found in great numbers where palm trees are abundant. The use of armadillo burrows possibly makes the movement of the rodents easier inside their own galleries.

  15. Genetic assessment of the Atlantic Forest bristle porcupine, Chaetomys subspinosus (Rodentia: Erethizontidae), an endemic species threatened with extinction.

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    Oliveira, C G; Martinez, R A; Giné, G A F; Faria, D M; Gaiotto, F A

    2011-05-24

    The bristle-spined porcupine, Chaetomys subspinosus, an endemic rodent from Atlantic Forest, was considered to be abundant in the recent past, but population reductions due to habitat loss and expansion of human activities caused this species to be included in the "vulnerable" category of the World Conservation Union Red List. We performed the first genetic assessment in natural populations of this focal species along its geographical distribution. Thirty-five non-invasive samples (hair) were collected from three natural populations in the Brazilian States of Sergipe, Bahia and Espírito Santo. Genetic similarity obtained by Jaccard's index, based on dominant RAPD and ISSR markers, varied between 25 and 100%. Four clusters, mainly coincident with the geographical distribution of the populations, were observed. Analysis of molecular variance based on 47 polymorphic loci showed that there was 15.99% genetic variability among populations and 84.01% within populations. The estimated genetic structure among populations (Φ(ST)) was 0.16. The populations may have formed a continuum along the past distribution of the Atlantic rainforest but historical events of human occupation resulted in recent divergence among sampled populations.

  16. The capybara, Hydrochoerus hydrochaeris (Mammalia: Rodentia, found at the archaeological site SC PRV 02, Santa Catarina Island, Brasil

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    Paulo César Simões-Lopes

    2005-11-01

    Full Text Available Santa Catarina Island possesses dozens of archeological sites where the skeletal remains of a great array of animals can be found. The goal of this study was to quantify the skeletal remains of capybaras found at the archeological site SC PRV 02 (1067 to 1735 BP, located in the northern part of the island, along the shores of Lagoa da Conceição, a saltwater lagoon. Thirty-seven skeletal fragments of at least 12 different individuals were identified. The anatomic regions of the capybaras most sought-after by pre-colonial inhabitants were the anterior and posterior limbs. About 40% of the skeletal fragments did not show any epiphyseal fusion with the shaft. Approximately 48% of the fragments found presented evidence of human activity. Our analyses suggest that capybaras played an important role in the diet of these inhabitants and that they were also used for the confection of different functional goods. We diagnosed the manipulation techniques used to obtain these goods, such as percussion and transversal section. The evidence of carbonization and superficial incisions indicates dismembering, preparation, and consumption of capybaras for feeding. Similar techniques were found at other archeological sites of the same age, suggesting that even though pre-colonial inhabitants of the island were considered to be fishermen, capybaras represented a well-appreciated resource.

  17. [Diet of the capybara Hydrochaeris hydrochaeris (Rodentia: Hydrocharidae) in Caño Limón, Arauca, Colombia].

    Science.gov (United States)

    Forero-Montaña, Jimena; Betancur, Julio; Cavelier, Jaime

    2003-06-01

    We studied the composition and seasonal variation of the diet of the capybara (Hydrochaeris hydrochaeris) in the flooded savannas of Caño Limón, Colombia. This was achieved by direct observation of the consumption patterns of these animals. The capybaras only consumed plants, and their diet included 89 species of 22 families. Sixty three percent of these plant species had not been reported before. The most commonly consumed plants (94% of the diet), belonged to the Poaceae, Cyperaceae, Leguminosae and Pontederiaceae. Only seven species represented 60% of the total diet: the grasses Hymenachne amplexicaulis (16.9%), Digitaria bicornis (4.5%) and Panicum maximum (4.4%) and the Cyperaceae Rynchospora corymbosa (4.4%). There was seasonal variation in the diet composition of capybaras.

  18. Redescription of Echinocoleus hydrochoeri (Travassos, 1916) (Nematoda: Trichuridae) from Hydrochoeris hydrochaeris Linnaeus, 1766 (Rodentia: Caviidae) from Argentina.

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    Robles, María del Rosario; Eberhardt, María Ayelen Teresita; Bain, Odile; Beldomenico, Pablo Martín

    2013-08-01

    Twenty-eight Capillariinae species have been recorded in rodents; 1 of these species was reported from a caviomorph rodent, Hydrochoeris hydrochaeris (capybara), and placed in the genus Echinocoleus by Moravec (1982). However, both original description and subsequent contributions of Echinocoleus hydrochoeri are poor and incomplete. In this paper, this species is redescribed, and a new geographical distribution is reported. The redescription is based on morphologic and morphometrical features; intestine ends in a cloaca beside ejaculatory duct, caudal bursa composed of 2 large ventrolateral lobes with a fleshy internal part and a membranous external part (they are not united dorsally with a membrane), 1 pair of caudal papillae, terminal part of cylindrical cirrus ornamented with thin and thick spines (and particular pattern distribution), sclerotized spicule in male, and vulvar appendage in female, and 3 bacillary bands (1 ventral and 2 lateral). Generic and specific analyses were performed to establish new standards for future studies on the systematic position of Capillariinae species. This study presents new morphological information and a new record of a capillariid species from Argentina.

  19. Biometric features of the capybara´s body and small intestine Hydrochoerus hydrochaeris Linnaeus, 1766 (Mammalia, Rodentia, Hydrochaeridae

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    Tarcízio Antônio Rego de Paula

    2006-09-01

    Full Text Available Biometric aspects of the body were analyzed, as well as some aspects of the small intestine of the capybara Hydrochoerus hydrochaeris wild species, particularly those that have been provoking economic interest in meat and leather production. Data such as age, corporal weight and length and thoracic perimeter and height were analyzed. Significant correlations were found between the age and the crown-rump (CR and snout-rump (SR corporal lengths, and between the corporal weight and the parameters of corporal length, thoracic perimeter and height, so that the age and the corporal weight could be obtained starting from more accessible biometric parameters, relative to corporal measurement. Most of the correlations were more significant in the male animals, especially the correlations between the corporal weight and the parameters CR length, thoracic perimeter and height, as well as the correlation among CR length and thoracic height and perimeter, suggesting the existence of possible sexual dimorphism. In relation to the small intestine, estimates were made of the length and volumetric capacity totals as well as those of its individual segments. The capybara possesses a small intestine that is relatively long, about five times longer than the corporal length, and with a volumetric capacity that is relatively high, representing 6.7% of the corporal weight.

  20. Three new karyotypes extend a Robertsonian fan in Ethiopian spiny mice of the genus Acomys I. Geoffroy, 1838 (Mammalia, Rodentia

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    Leonid Lavrenchenko

    2011-12-01

    Full Text Available Three new karyotypes (2n=40, 44, 52 are described revealing what are probably new cryptic species of Ethiopian spiny mice. Two other diploid numbers have already been reported for the country (2n=36 and 68 and, overall, the five known karyotypic forms constitute a common lineage differentiated by a Robertsonian process. Such arrays of karyotypic forms are known as a ‘Robertsonian fan’. This view of the situation in Ethiopian Acomys I. Geoffroy, 1838 is based on standard chromosomal morphology that reveals a constant FN (68 and needs further investigation of chromosome homology by differential staining and/or molecular cytogenetic techniques as well as further molecular phylogenetic analysis.

  1. Three new karyotypes extend a Robertsonian fan in Ethiopian spiny mice of the genus Acomys I. Geoffroy, 1838 (Mammalia, Rodentia).

    Science.gov (United States)

    Lavrenchenko, L A; Nadjafova, R S; Bulatova, N Sh

    2011-01-01

    Three new karyotypes (2n=40, 44, 52) are described revealing what are probably new cryptic species of Ethiopian spiny mice. Two other diploid numbers have already been reported for the country (2n=36 and 68) and, overall, the five known karyotypic forms constitute a common lineage differentiated by a Robertsonian process. Such arrays of karyotypic forms are known as a 'Robertsonian fan'. This view of the situation in Ethiopian Acomys I. Geoffroy, 1838 is based on standard chromosomal morphology that reveals a constant FN (68) and needs further investigation of chromosome homology by differential staining and/or molecular cytogenetic techniques as well as further molecular phylogenetic analysis.

  2. Comparative gastrointestinal morphology of three small mammalian insectivores: Acomys spinosissimus (Rodentia), Crocidura cyanea (Eulipotyphla), and Amblysomus hottentotus (Afrosoricida).

    Science.gov (United States)

    Boonzaier, Julia; Van der Merwe, Elizabeth L; Bennett, Nigel C; Kotzé, Sanet H

    2013-06-01

    The gastrointestinal morphology was investigated in three mammalian insectivorous species, namely Acomys spinosissimus, Crocidura cyanea, and Amblysomus hottentotus. The aim of the study was to provide a comprehensive morphological comparison between the different species and to explore whether anatomical gastrointestinal adaptations are associated with the insectivorous diet of these species. The shape, proportional length, and proportional surface areas of the different gastrointestinal regions were recorded and compared in the three insectivores. Hematoxylin and Eosin (H&E) and Alcian Blue/Periodic Acid Schiff (AB/PAS) were used for morphological assessment. In all three species, the stomach was simple and uncompartmentalized. The internal aspect of the stomach in A. spinosissimus was hemi-glandular, containing stratified squamous epithelium in the fundus, with glandular epithelium in the body and pyloric region. However, C. cyanea and A. hottentotus had wholly glandular stomachs. Paneth cells were not observed in the intestinal tracts of C. cyanea and A. hottentotus. Acomys spinosissimus was the only species studied that had a cecum. The proximal colonic region of A. spinosissimus had V-shaped mucosal folds. Histologically, C. cyanea had villi throughout the entire gastrointestinal tract (GIT), whereas for A. hottentotus villi were not present in the most distal gastrointestinal regions. In both C. cyanea and A. hottentotus, longitudinal mucosal folds were present in the distal part of the colon. The GITs of C. cyanea and A. hottentotus showed little morphological differentiation namely, a simple, glandular stomach and the lack of a cecum.

  3. Cytochrome b sequences reveal Acomys minous (Rodentia, Muridae) paraphyly and answer the question about the ancestral karyotype of Acomys dimidiatus.

    Science.gov (United States)

    Barome, P O; Lymberakis, P; Monnerot, M; Gautun, J C

    2001-01-01

    Sequences of the cytochrome b (cyt b) mitochondrial gene show that the spiny mouse Acomys from Crete, known as the endemic species A. minous, is composed of two distinct maternal lineages ("A" and "B"). Group "A" sequences cluster with A. nesiotes (Cyprus) and group "B" sequences cluster with A. cilicicus (Turkey), which is evidence of paraphyly of A. minous in regard to these two species. From cyt b sequences, the three taxa are very closely related to A. cahirinus (Egypt): the maximum divergence found among these sequences is 1.6%, which is equivalent to the intraspecific diversity observed in other Acomys species. Paleozoology evidenced that man unintentionally introduced Acomys into Crete and Cyprus during antiquity. The divergence time between Acomys cyt b sequences found in Crete was estimated at 0.4 Myr, which means that the diversity observed did not appear after the introduction but reflects a much more ancient polymorphism. Cytochrome b phylogeny and cytogenetic data together comprise evidence that, within the species A. dimidiatus (Saudi Arabia, Israel, Egypt), it is the karyotypic form with 36 chromosomes that derives from the form with 38 chromosomes, due to a single acrocentric fusion.

  4. On cognitive ecology and the environmental factors that promote Alzheimer disease: lessons from Octodon degus (Rodentia: Octodontidae).

    Science.gov (United States)

    Rivera, Daniela S; Inestrosa, Nibaldo C; Bozinovic, Francisco

    2016-02-20

    Cognitive ecologist posits that the more efficiently an animal uses information from the biotic and abiotic environment, the more adaptive are its cognitive abilities. Nevertheless, this approach does not test for natural neurodegenerative processes under field or experimental conditions, which may recover animals information processing and decision making and may explain, mechanistically, maladaptive behaviors. Here, we call for integrative approaches to explain the relationship between ultimate and proximate mechanisms behind social behavior. We highlight the importance of using the endemic caviomorph rodent Octodon degus as a valuable natural model for mechanistic studies of social behavior and to explain how physical environments can shape social experiences that might influence impaired cognitive abilities and the onset and progression of neurodegenerative disorders such as Alzheimer disease. We consequently suggest neuroecological approaches to examine how key elements of the environment may affect neural and cognitive mechanisms associated with learning, memory processes and brain structures involved in social behavior. We propose the following three core objectives of a program comprising interdisciplinary research in O. degus, namely: (1) to determine whether diet types provided after weaning can lead to cognitive impairment associated with spatial memory, learning and predisposing to develop Alzheimer disease in younger ages; (2) to examine if early life social experience has long term effects on behavior and cognitive responses and risk for development Alzheimer disease in later life and (3) To determine if an increase of social interactions in adult degu reared in different degree of social stressful conditions alter their behavior and cognitive responses.

  5. On the Origin and Evolution of the Extant System of B Chromosomes in Oryzomyini Radiation (Rodentia, Sigmodontinae).

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    Ventura, Karen; O'Brien, Patricia Caroline Mary; do Nascimento Moreira, Camila; Yonenaga-Yassuda, Yatiyo; Ferguson-Smith, Malcolm Andrew

    2015-01-01

    Heterogeneous supernumerary chromosomes (Bs) are recognized in the oryzomyines Holochilus brasiliensis, Nectomys rattus, N. squamipes, Oligoryzomys flavescens and Sooretamys angouya, representing about 10% of all known B-containing rodent species. They provide an outstanding model for understanding the origin, evolution and diversity of Bs in a phylogenetic context. Therefore, whole chromosome-specific probes were generated from flow-sorted Holochilus brasiliensis (HBR) autosomes 11 and 25+26 and chromosomes X, Y and Bs. Hybridizations were performed on male metaphases of 15 Oryzomyini species of which 3 are B-containing species. The results reveal that among the species sampled, 12 of them, belonging to a monophyletic Oryzomiyini subclade, are positive for an anonymous Oryzomyini shared heterochromatic region (OSHR) on both sex chromosomes. The OSHR is also present on Bs of Holochilus brasiliensis, Nectomys rattus and N. squamipes but not on Bs of O. flavescens and S. angouya. Two distinct additional OSHR/autosome associations are observed on S. angouya. The three species that are OSHR negative belong to an outgroup. Molecular dating suggests that the OSHR originated between 7.8 and 3 Mya on ancestral sex chromosomes. A tentative explanation for the OSHR-positive nature of B regions in three species could be that transposable elements (TEs) from this specific sex chromosome region may have invaded existing B chromosomes. The presence of the OSHR on entire Xp and Yp adjacent to interstitial telomeric sequences at pericentromeric positions, as observed in Drymoreomys albimaculatus, show a similar organization as on B chromosomes in Nectomys squamipes. The diversity of the Oryzomyini Bs in number, size, morphology and genetic content may be explained by the independent origin of B chromosomes in different subgroups of species, with Bs in Holochilus brasiliensis, Nectomys squamipes and N. rattus sharing the OSHR with sex chromosomes, and those in Oligoryzomys flavescens and Sooretamys angouya lacking OSHR in Bs. The species-specific pattern of Bs is probably a consequence of their independent evolutionary origin.

  6. Paraspidodera uncinata (Nematoda, Lauroiinae as parasite of Cavia magna and Cavia aperea (Rodentia, Caviidae in southern Brazil

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    Ana Gabriela da Silva Rocha

    2015-05-01

    Full Text Available Out of the 5 species of Guinea pig registered for Brazil, 4 (Cavia fulgida, C. porcellus, C. aperea, and C. magna have already been reported as hosts of Paraspidodera uncinata. The rodent species C. magna and C. aperea are small-sized mammals, with terrestrial habits, which occur from southern Brazil to eastern Uruguay. Guinea pig specimens donated for research were necropsied for the analysis of endoparasites, and the nematodes found were identified as P. uncinata. The microhabitats of this species were the small and large intestines in C. magna and the large intestine in C. aperea. The prevalence of P. uncinata in the hosts was 60% in C. magna (n = 5 and 14% in C. aperea (n = 7. The record of P. uncinata in different Guinea pig species allows inferring that the foraging mode is similar in the different locations where they occur in southern Brazil, because, perhaps, the infection of hosts has occurred through the ingestion of vegetables contaminated with P. uncinata eggs. This study contributes to knowledge on the helminth fauna of C. magna and C. aperea in southern Brazil.

  7. A new host of Trypanosoma cruzi from Jujuy, Argentina: octodontomys gliroides (Gervais & D'Orbigny, 1844 (Rodentia, Octodontidae

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    Nicolas J. Schweigmann

    1992-06-01

    Full Text Available To identify wild hosts of Trypanosoma cruzi, surveys were conducted in the subandean valleys of Jujuy Province, Argentina, between June 1986 and March 1987. Seventy two mammals from 13 different species were examined by xenodiagnosis. Fifty two of them were mostly roedents trapped at the localities of Maimará, León and Tilcara, and the remainder had been kept in captivity at the Estación Biológica Experimental, in Jujuy. Trypanosoma cruzi infection was detected only in 2 Octodontomys gliroides (2 pos./8 exam. 25% from all 72 examined mammals. Isolates were called Octodontomys Argentina 1 and 2 (OA1 and OA2. Both infected animals were caught at the archaelogical ruin of Pucará, at Tilcara. Repeated searches for triatomines in the ruin itself and in neighbour houses rendered negative results. Groups of mice inoculated with either OA1 or OA2 isolates became infected between 7 (OA1 to 12 days (OA2 postinoculation PI. Parasitemia peaks were observed between day 12th - 14th PI. Scarce amastigote nests were found in myocardium and skeletal muscle. Mortality was observed only for mice inoculated with OA1. Isoenzyme patterns of OA1 and OA2 were identical to one found in dogs and slightly different from that of human parasites in Argentina. Bones from Octodontomys sp., were recently found in a cave, dated 10200-8600 BC, in Pumamarca, near Tilcara, Jujuy. There are evidences that O. gliroides cohabited with man in ancient times and was associated to the domestic cycle of T. cruzi transmission, playing a role like that of domestic cavies. in Bolivia.

  8. Thrichomys laurentius (Rodentia; Echimyidae as a putative reservoir of Leishmania infantum and L. braziliensis: patterns of experimental infection.

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    André Luiz Rodrigues Roque

    Full Text Available The importance of the genus Thrichomys in the retention of infection and transmission of Leishmania species is supported by previous studies that describe an ancient interaction between caviomorphs and trypanosomatids and report the natural infection of Thrichomys spp. Moreover, these rodents are widely dispersed in Brazil and recognized as important hosts of other tripanosomatids. Our main purpose was to evaluate the putative role of Thrichomys laurentius in the retention of infection and amplification of the transmission cycle of Leishmania infantum and L. braziliensis. Male and female T. laurentius (n = 24 born in captivity were evaluated for the retention of infection with these Leishmania species and followed up by parasitological, serological, hematological, biochemical, histological, and molecular assays for 3, 6, 9, or 12 months post infection (mpi. T. laurentius showed its competence as maintenance host for the two inoculated Leishmania species. Four aspects should be highlighted: (i re-isolation of parasites 12 mpi; (ii the low parasitic burden displayed by T. laurentius tissues; (iii the early onset and maintenance of humoral response, and (iv the similar pattern of infection by the two Leishmania species. Both Leishmania species demonstrated the ability to invade and maintain itself in viscera and skin of T. laurentius, and no rodent displayed any lesion, histological changes, or clinical evidence of infection. We also wish to point out the irrelevance of the adjective dermotropic or viscerotropic to qualify L. braziliensis and L. infantum, respectively, when these species are hosted by nonhuman hosts. Our data suggest that T. laurentius may act at least as a maintenance host of both tested Leishmania species since it maintained long-lasting infections. Moreover, it cannot be discarded that Leishmania spp. infection in free-ranging T. laurentius could result in higher parasite burden due the more stressing conditions in the wild. Therefore the tissular parasitism of the skin, infectiveness to the vector, and amplification of the transmission cycle of both Leishmania species could be expected.

  9. Evolutionary and Biological Implications of Dental Mesial Drift in Rodents: The Case of the Ctenodactylidae (Rodentia, Mammalia)

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    Gomes Rodrigues, Helder; Solé, Floréal; Charles, Cyril; Tafforeau, Paul; Vianey-Liaud, Monique; Viriot, Laurent

    2012-01-01

    Dental characters are importantly used for reconstructing the evolutionary history of mammals, because teeth represent the most abundant material available for the fossil species. However, the characteristics of dental renewal are presently poorly used, probably because dental formulae are frequently not properly established, whereas they could be of high interest for evolutionary and developmental issues. One of the oldest rodent families, the Ctenodactylidae, is intriguing in having longstanding disputed dental formulae. Here, we investigated 70 skulls among all extant ctenodactylid genera (Ctenodactylus, Felovia, Massoutiera and Pectinator) by using X-ray conventional and synchrotron microtomography in order to solve and discuss these dental issues. Our study clearly indicates that Massoutiera, Felovia and Ctenodactylus differ from Pectinator not only by a more derived dentition, but also by a more derived eruptive sequence. In addition to molars, their dentition only includes the fourth deciduous premolars, and no longer bears permanent premolars, conversely to Pectinator. Moreover, we found that these premolars are lost during adulthood, because of mesial drift of molars. Mesial drift is a striking mechanism involving migration of teeth allowed by both bone remodeling and dental resorption. This dental innovation is to date poorly known in rodents, since it is only the second report described. Interestingly, we noted that dental drift in rodents is always associated with high-crowned teeth favoring molar size enlargement. It can thus represent another adaptation to withstand high wear, inasmuch as these rodents inhabit desert environments where dust is abundant. A more accurate study of mesial drift in rodents would be very promising from evolutionary, biological and orthodontic points of view. PMID:23185576

  10. Evolutionary and biological implications of dental mesial drift in rodents: the case of the Ctenodactylidae (Rodentia, Mammalia.

    Directory of Open Access Journals (Sweden)

    Helder Gomes Rodrigues

    Full Text Available Dental characters are importantly used for reconstructing the evolutionary history of mammals, because teeth represent the most abundant material available for the fossil species. However, the characteristics of dental renewal are presently poorly used, probably because dental formulae are frequently not properly established, whereas they could be of high interest for evolutionary and developmental issues. One of the oldest rodent families, the Ctenodactylidae, is intriguing in having longstanding disputed dental formulae. Here, we investigated 70 skulls among all extant ctenodactylid genera (Ctenodactylus, Felovia, Massoutiera and Pectinator by using X-ray conventional and synchrotron microtomography in order to solve and discuss these dental issues. Our study clearly indicates that Massoutiera, Felovia and Ctenodactylus differ from Pectinator not only by a more derived dentition, but also by a more derived eruptive sequence. In addition to molars, their dentition only includes the fourth deciduous premolars, and no longer bears permanent premolars, conversely to Pectinator. Moreover, we found that these premolars are lost during adulthood, because of mesial drift of molars. Mesial drift is a striking mechanism involving migration of teeth allowed by both bone remodeling and dental resorption. This dental innovation is to date poorly known in rodents, since it is only the second report described. Interestingly, we noted that dental drift in rodents is always associated with high-crowned teeth favoring molar size enlargement. It can thus represent another adaptation to withstand high wear, inasmuch as these rodents inhabit desert environments where dust is abundant. A more accurate study of mesial drift in rodents would be very promising from evolutionary, biological and orthodontic points of view.

  11. In the wake of invasion: tracing the historical biogeography of the South American cricetid radiation (Rodentia, Sigmodontinae.

    Directory of Open Access Journals (Sweden)

    Rafael N Leite

    Full Text Available The Great American Biotic Interchange (GABI was greatly influenced by the completion of the Isthmus of Panama and impacted the composition of modern faunal assemblages in the Americas. However, the contribution of preceding events has been comparatively less explored, even though early immigrants in the fossil records are evidence for waif dispersals. The cricetid rodents of the subfamily Sigmodontinae are a classic example of a species-rich South American radiation resulting from an early episode of North American invasion. Here, we provide a temporal and spatial framework to address key aspects of the historical biogeography and diversification of this diverse mammal group by using mitochondrial and nuclear DNA datasets coupled with methods of divergence time estimation, ancestral area reconstruction and comparative phylogenetics. Relaxed-clock time estimates indicate that divergence of the Sigmodontinae began in the middle-late Miocene (ca. 12-9 Ma. Dispersal-vicariance analyses point to the arrival of a single lineage of northern invaders with a widespread ancestral distribution and imply that the initial differentiation between Central and South America gave rise to the most basal groups within the subfamily. These two major clades diversified in the late Miocene followed by the radiation of main tribes until the early Pliocene. Within the Oryzomyalia, tribes diverged initially in eastern South America whereas multiple dispersals into the Andes promoted further diversification of the majority of modern genera. A comparatively uniform background tempo of diversification explains the species richness of sigmodontines across most nodes, except for two akodontine genera with recent increases in diversification rates. The bridging of the Central American seaway and episodes of low sea levels likely facilitated the invasion of South America long before the onset of the post-Isthmian phase of the GABI.

  12. In the Wake of Invasion: Tracing the Historical Biogeography of the South American Cricetid Radiation (Rodentia, Sigmodontinae)

    OpenAIRE

    Leite, Rafael N; Sergios-Orestis Kolokotronis; Francisca C Almeida; Werneck, Fernanda P.; Duke S Rogers; Marcelo Weksler

    2014-01-01

    The Great American Biotic Interchange (GABI) was greatly influenced by the completion of the Isthmus of Panama and impacted the composition of modern faunal assemblages in the Americas. However, the contribution of preceding events has been comparatively less explored, even though early immigrants in the fossil records are evidence for waif dispersals. The cricetid rodents of the subfamily Sigmodontinae are a classic example of a species-rich South American radiation resulting from an early e...

  13. In the wake of invasion: tracing the historical biogeography of the South American cricetid radiation (Rodentia, Sigmodontinae).

    Science.gov (United States)

    Leite, Rafael N; Kolokotronis, Sergios-Orestis; Almeida, Francisca C; Werneck, Fernanda P; Rogers, Duke S; Weksler, Marcelo

    2014-01-01

    The Great American Biotic Interchange (GABI) was greatly influenced by the completion of the Isthmus of Panama and impacted the composition of modern faunal assemblages in the Americas. However, the contribution of preceding events has been comparatively less explored, even though early immigrants in the fossil records are evidence for waif dispersals. The cricetid rodents of the subfamily Sigmodontinae are a classic example of a species-rich South American radiation resulting from an early episode of North American invasion. Here, we provide a temporal and spatial framework to address key aspects of the historical biogeography and diversification of this diverse mammal group by using mitochondrial and nuclear DNA datasets coupled with methods of divergence time estimation, ancestral area reconstruction and comparative phylogenetics. Relaxed-clock time estimates indicate that divergence of the Sigmodontinae began in the middle-late Miocene (ca. 12-9 Ma). Dispersal-vicariance analyses point to the arrival of a single lineage of northern invaders with a widespread ancestral distribution and imply that the initial differentiation between Central and South America gave rise to the most basal groups within the subfamily. These two major clades diversified in the late Miocene followed by the radiation of main tribes until the early Pliocene. Within the Oryzomyalia, tribes diverged initially in eastern South America whereas multiple dispersals into the Andes promoted further diversification of the majority of modern genera. A comparatively uniform background tempo of diversification explains the species richness of sigmodontines across most nodes, except for two akodontine genera with recent increases in diversification rates. The bridging of the Central American seaway and episodes of low sea levels likely facilitated the invasion of South America long before the onset of the post-Isthmian phase of the GABI.

  14. Dietary selection in Mastomys natalensis (Rodentia: Muridae) in the maize agro-ecosystems of central and southwestern Tanzania

    DEFF Research Database (Denmark)

    Odhiambo, Richard O; Makundi, Rhodes H; Leirs, Herwig;

    2008-01-01

    We studied the feeding habits of Mastomys natalensis by analysing a total of 2934 stomachs from individuals snap trapped from maize fields and the surrounding fallow land of central and southwestern Tanzania between February 2001 and October 2002. Mastomys natalensis had a wide range of food item...

  15. Leishmania mexicana in Proechimys iheringi denigratus Moojen (Rodentia, Echimyidae in a region endemic for American cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Air C. Barretto

    1985-12-01

    Full Text Available Three isolates of Leishmania were recovered from five of 27 specimens of the rodent Proechimys iheringi denigratus Moojen captured near Três Braços in the Atlantic Forest region of Bahia, Brazil. Two of these isolates were recovered from hamsters inoculated with a pooled triturate of liver, spleen and skin tissue from apparently healthy P. i. denigratus. The third isolate was recovered from a triturate of only skin tissue from another. Metastasis was observed in the inoculated hamsters, the parasites grew abundantly in artificial media and a typical suprapylarial pattern of infection in Lutzomyia longipalpis was produced indicating that the parasites belong to the Leishmania mexicana complex. All isolates reacted with Leishmania mexicana mexicana and Leishmania mexicana amazonensis monoclonal antibodies. The isoenzyme analysis differentiated these isolates from standard isolates of L. m. mexicana, L. m. amazonensis, L. m. aristedesi, L. m. pifanoi, L. m. garnhami and L. m. ssp.(Goiás-W. Barbosa. These isolates seem to be a subspecies of L. mexicana very closely related to L. m. amazonensis from which they differ by decreased electrophoretic mobility of GPI, PEP and ALAT. This is the first record of the isolation of a parasite of thegenus Leishmania in a rodent captured in the State of Bahia.Três isolados de Leishmania foram obtidos de cinco entre 27 exemplares do roedor Proechimys iheringi denigratus, capturados na região de Três Braços, na mata atlântica do Estado da Bahia, Brasil. O isolamento desse parasito foi feito através de inoculação de triturado de pele, baço e fígado em patas de hamsters. Em pelo menos um dos casos, (MTB-574, o parasito foi isolado da pele. Metas- tase foi observada nos hamsters inoculados, os parasitos cresceram abundantemente em meios artificiais de cultura e um padrão suprapapilario típico foi obtido em Lutzomyia longipalpis, indicando que o parasito pertence ao complexo L. mexicana. Todos os isolados reagiram positivamente com anticorpos monoclonais de L. m. mexicana e L. m. amazonensis. A análise isoenzimática diferenciou o parasito de isolados padrões de L. m. mexicana. L. m. amazonensis. L. m. aristedesi. L. m. pifanoi. L. m. garnhami e L. m. ssp(Goiás-W. Barbosa. O parasito parece ser uma subespécie de L. mexicana muito próxima à L. m. amazonensis, da qual difere pela menor mobilidade eletroforêtica de GPI, PEP e ALAT. Este e o primeiro registro do isolamento de um parasito do gênero Leishmania em um roedor capturado no Estado da Bahia.

  16. Glirinae (Gliridae, Rodentia) from the type area of the Aragonian and adjacent areas (provinces of Teruel and Zaragoza, Spain)

    NARCIS (Netherlands)

    Daams, R.

    1985-01-01

    This paper, the first in a series of monographs on the mammal faunas from the type area of the Aragonian and adjacent areas in the provinces of Teruel and Zaragoza, deals with the description and palaeoenvironmental interpretation of the Glirinae (Gliridae: dormice).

  17. PATRONES DE REPLICACIÓN Y BANDEO NO DIFERENCIAL EN ARDILLAS COLOMBIANAS DEL GÉNERO SCIURUS (RODENTIA, SCIURIDAE

    Directory of Open Access Journals (Sweden)

    Bueno Marta Lucia

    2012-08-01

    Full Text Available Las ardillas colombianas muestran una gran variabilidad citogenética lo que ha despertado el interés en ahondar aspectos evolutivos en el grupo. Para esto varias herramientas de bandeo cromosómico deben ser analizadas con detenimiento en complemento con la técnica clásica de bandeo G. Estas técnicas incluyen otras bandas diferenciales como la banda Q y R y bandas no diferenciales tipo banda C y NOR. Se explica la utilidad de cada uno de estos complementos en el análisis citogenético de especies y las observaciones para los citotipos de las ardillas colombianas.

  18. A taxonomic revision of the Pleistocene Hystrix (Hystricidae, Rodentia) from Eurasia with notes on the evolution of the family

    NARCIS (Netherlands)

    Weers, van D.J.

    2005-01-01

    Measurements of many hundreds of the high-crowned cheek teeth of Hystrix specimens from the Euro-Asiatic Pleistocene in the collections of European and Asiatic institutions have been compared with extant species for a revision of the genus. A review is given about the extant genera and species of th

  19. Aepyosciurinae -- a new subfamily of Sciuridae (Rodentia, Mammalia) from basal loess deposits at the northeastern border of Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Aepyosciurinae, a new subfamily of Sciuridae, were found at the base of the early Pleistocene loess deposits in Dongxiang County, Gansu Province. Its unilaterally hypsodont and lophodont cheek teeth are unique among the sciurids so far known all over the world. Certain degree of similarity can be observed between the cheek teeth of the new subfamily and the Anomalurinae living in tropical and subtropical forests in central and western Africa. Aepyosciuris orientalis gen. et sp. nov. might have lived in montaneous woodland or grassland and lived on harder leaves, barks, or even grass. This tends to show that the northeastern border area of the Tibetan Plateau had been lifted considerably high in early Pleistocene (ca. 2 Ma), with drier climate, becoming a suitable habitat for Aepyosciurus orientalis.

  20. Potential distribution and new records of Trinomys species (Rodentia: Echimyidae in the state of Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Nina Attias

    2009-06-01

    Full Text Available The spiny rats of the genus Trinomys Thomas, 1921 have a broad distribution in the Atlantic Forests of southeastern Brazil. However, some species are known only from their type locality and adjacent areas. In our study, nine areas in the state of Rio de Janeiro were surveyed and three species of the genus were captured - Trinomys dimidiatus (Günther, 1877, T. setosus (Desmarest, 1817 and T. gratiosus bonafidei (MOOJEN, 1948. We extended the distribution of T. gratiosus bonafidei in 100 km, in a straight line to the northwest, and into an area of Semidecidual Seasonal Forest. We captured T. setosus, which had not been previously recorded in the state, in the municipality of Cambuci, extending its distribution 150 km, in a straight line to the east of its closest record, in Juiz de Fora, state of Minas Gerais. The state of Rio de Janeiro has now six recognized species of Trinomys, however none of them were collected above 1300 m of altitude. We used occurrence points provided by our inventories data and from the literature to model the potential distribution of Trinomys species. We used climatic, topographic and phytogeographic variables to prepare the potential distribution maps. The algorithm used for modeling was provided by the software Maxent, version 3.2.1. Although species boundaries within Trinomys in Rio de Janeiro State are not yet clear, their distributions seem to be parapatric, except for T. iheringi and T. dimidiatus.

  1. Changes on Schistosoma mansoni (Digenea: Schistosomatidae worm load in Nectomys squamipes (Rodentia: Sigmodontinae concurrently infected with Echinostoma paraensei (Digenea: Echinostomatidae

    Directory of Open Access Journals (Sweden)

    Arnaldo Maldonado Júnior

    2001-09-01

    Full Text Available The water rat, Nectomys squamipes, closely involved in schistosomiasis transmission in Brazil, has been found naturally infected simultaneously by Schistosoma mansoni and Echinostoma paraensei. Laboratory experiments were conducted to verify parasitic interaction in concurrent infection. It was replicated four times with a total of 42 water rats and essayed two times with 90 mice pre-infected with E. paraensei. Rodents were divided into three groups in each replication. A wild strain recently isolated from Sumidouro, RJ, and a laboratory strain of S. mansoni from Belo Horizonte (BH was used. Rats infected with E. paraensei were challenged 4 weeks later with S. mansoni and mice 2 or 6 weeks after the infection with S. mansoni. Necropsy took place 8 weeks following S. mansoni infection. The N. squamipes treatment groups challenged with S. mansoni RJ strain showed a significant decrease (80 and 65% in the S. mansoni parasite load when compared with their respective control groups. There was a significant change or no change in the hosts challenged with the BH strain. The persistence time of E. paraensei within host was extended in relation to control groups, with a consequent enhancement of the number of recovered worm. An E. paraensei strain-specific influence on S. mansoni parasitism is reported. This paper presents some experimental data about this interaction in N. squamipes and Mus musculus.

  2. El aparato masticador del género extinto Actenomys Burmeister, 1888 (Rodentia, Ctenomyidae: inferencias sobre su modo de vida

    Directory of Open Access Journals (Sweden)

    Moreira, G. J.

    2000-04-01

    Full Text Available The genus Actenomys is registered from Plioceno sediments of Buenos Aires province, Argentina. Anatomy of skull and dentition of the genus is described, giving special emphasis to the origin and insertion points of the masticatory musculature. Actenomys is compared with the extant fossorial rodent of the genus Ctenomys, and the development of the masticatory muscles and their degree of functionality are inferred. It is concluded that Actenomys presents a less robust skull, with a masticatory musculature in agreement and incisives with great procumbency. This evidence could explain a possible adaptation of Actenomys to dig using the incisives and an adaptation to live in habitats of higher humidity than the extant forms.Se describe la anatomía cráneo-dentaria del género Actenomys, registrado en sedimentos del Plioceno de la provincia de Buenos Aires (República Argentina, con especial énfasis los puntos de origen e inserción de la musculatura masticatoria; se lo compara con el roedor fosorial viviente del género Ctenomys, infiriéndose el desarrollo de los músculos masticatorios y su grado de funcionalidad. Se concluye que Actenomys presenta un cráneo menos robusto, con una musculatura masticatoria acorde e incisivos procumbentes, lo que podría explicar una posible adaptación para cavar con los mismos, y que estaría adaptado a vivir en ambientes con un porcentaje de humedad mayor que las formas actuales.

  3. Teasing apart socially-induced infertility in non-reproductive female Damaraland mole-rats, Fukomys damarensis (Rodentia: Bathyergidae).

    Science.gov (United States)

    Bennett, Nigel C

    2011-12-01

    The Damaraland mole-rat is a subterranean mammal exhibiting extreme reproductive skew with a single reproductive female in each colony responsible for procreation. Non-reproductive female colony members are physiologically suppressed while in the colony, exhibiting reduced concentrations of plasma luteinizing hormone (LH) and a decreased response of the pituitary, as measured by the release of bioactive LH, to an exogenous dose of gonadotrophin releasing hormone (GnRH). Removal of the reproductive female from the colony results in an elevation of LH and an enhanced response of the pituitary to a GnRH challenge in non-reproductive females comparable to reproductive females, implying control of reproduction in these individuals by the reproductive female. The Damaraland mole-rat is an ideal model for investigating the physiological and behavioral mechanisms that regulate the hypothalamo-pituitary-gonadal axis. In contrast, we know less about the control of reproduction at the level of the hypothalamus. The immunohistochemistry of the GnRH system of both reproductive and non-reproductive female Damaraland mole-rats has revealed no significant differences with respect to morphology, distribution or numbers of immunoreactive GnRH perikarya. We examined whether the endogenous opioid peptide beta-endorphin was responsible for the inhibition of the release of the GnRH from the neurons indirectly by measuring LH concentrations in these non-reproductive females following single, hourly and 8 hourly injections of the opioid antagonist naloxone. The results imply that the endogenous opioid peptide, beta-endorphin, is not responsible for the inhibition of GnRH release from the perikarya in non-reproductive females. Preliminary data examining the circulating levels of cortisol also do not support a role for circulating glucocorticoids. The possible role of kisspeptin is discussed.

  4. Behavior and foraging technique of the Ingram's squirrel Guerlinguetus ingrami (Sciuridae: Rodentia in an Araucaria moist forest fragment

    Directory of Open Access Journals (Sweden)

    Calebe Pereira Mendes

    2014-06-01

    Full Text Available This work describes the foraging techniques, body positions and behavior of free-ranging Ingram's squirrel Guerlinguetus ingrami Thomas, 1901 in a region of the Araucaria moist forest, in the Atlantic Forest of southern Brazil. The animals were observed using the "all occurrence sampling" method with the aid of binoculars and a digital camcorder. All behaviors were described in diagrams and an ethogram. We recorded five basic body positions, 24 behaviors, two food choices, and three feeding strategies utilized to open fruits of Syagrus romanzoffiana (Cham., the main food source of Ingram's squirrels. We also observed a variance in the animals' stance, which is possibly influenced by predation risk, and discuss the causes of some behaviors.

  5. Syphacia obvelata (Nematode, Oxyuridae) infecting laboratory mice Mus musculus (Rodentia, Muridae): phylogeny and host-parasite relationship.

    Science.gov (United States)

    Abdel-Gaber, Rewaida

    2016-03-01

    Syphacia obvelata is a pinworm nematode parasite infecting man and laboratory animals in high abundance. This parasitological study was carried out during the period of March 2014-February 2015 to investigate the helminth parasites infecting the laboratory mice Mus musculus in the Animal House at Cairo University, Egypt. The prevalence of S. obvelata in M. musculus was 75.0 %. The extent of infection with S. obvelata is analyzed according to the sex of the host mice. It was shown that the prevalence of male infection was greater than female worms. Morphological characterization revealed that the present Oxyurid species possesses a rounded cephalic end with less developed lips, esophagus divided into cylindrical corpus, and globular bulb supported internally with valvular apparatus; three mamelons are located at the ventral surface with a single chitinized spicule and a gubernaculum provided with an accessory hook in males, and ovijector apparatus opens ventrally by the vulva surrounded by protruded lips in female worms. Body of the male was 0.623-1.130 (0.830 ± 0.11) mm long and 0.092-0.130 (0.110 ± 0.01) mm wide; the esophagus was 0.164-0.280 (0.210 ± 0.01) mm long; the nerve ring and excretory pore are located at 0.035-0.132 (0.073 ± 0.01) and 0.087-0.191 (0.145 ± 0.01) mm from the anterior end, respectively, while the female measured 2.930-4.650 (3.540 ± 0.1) mm long and 0.120-0.232 (0.156 ± 0.001) mm wide; the esophagus was 0.213-0.410 (0.342 ± 0.01) mm long; the nerve ring, excretory pore, and vulval opening are located at 0.026-0.157 (0.121 ± 0.01), 0.134-0.243 (0.195 ± 0.01), and 0.323-0.632 (0.546 ± 0.11) mm from the anterior end, respectively; eggs measured 0.120-0.139 (0.129 ± 0.001) mm long and 0.030-0.052 (0.045 ± 0.001) mm wide. It compared morphometrically with other Syphacia species described previously and showed little differences in measurements. Molecular characterization based on small subunit ribosomal DNA (rDNA) was done to confirm the obtained morphological and morphometric results. A preliminary genetic comparison between SSU rDNA of the present parasite and other species of Oxyuridae places it as a putative sister taxon to other S. obvelata.

  6. A new genus of aplodontid rodent (Mammalia, Rodentia) from the late Oligocene of northern Junggar Basin, China.

    Science.gov (United States)

    Bi, Shundong; Meng, Jin; McLean, Sarah; Wu, Wenyu; Ni, Xijun; Ye, Jie

    2013-01-01

    A new genus and species of aplodontid rodent, Proansomys dureensis, from the late Oligocene of the northern Junggar Basin of China is described. The new genus is referred to as Ansomyinae because the ectoloph on the upper cheek teeth, although not fully crested, has attained the same characteristic bucket-handle-shaped configuration as other members of the subfamily. It represents the earliest record of the subfamily yet discovered in Asia and is more plesiomorphic than species of the genus Ansomys in having a partly crested ectoloph, a lower degree of lophodonty, and less complex tooth basins (lacking accessory lophules). Proansomys has transitional features between Prosciurus and Ansomys, suggesting that the Ansomyinae derived from a group of aplodontids related to Prosciurus, as did other advanced aplodontid rodents. This provides new light on the paleobiogeography of the Ansomyinae.

  7. Establishment of Orientia tsutsugamushi Lc-1 (Rickettsiales: Rickettsiaceae) infection in ICR outbred mice (Rodentia: Muridae) by needle challenge.

    Science.gov (United States)

    Lurchachaiwong, Woradee; Chan, Teik-Chye; Richards, Allen L; McCardle, Wesley; Schuster, Anthony L

    2014-05-01

    Orientia tsutsugamushi is a pathogen transmitted by Leptotrombidium that causes scrub typhus. To develop an infection mouse model, a mite-derived isolate of O. tsutsugamushi was established from a laboratory-maintained colony of Leptotrombidium chiangraiensis (O. tsutsugamushi Lc-1). This Lc-1 isolate was initially presented to ICR (CD-1) mice by feeding an infected Lc chigger on the ear of a mouse. Once the Lc-1 was adapted to the ICR mice, quantitative real-time polymerase chain reaction was used to investigate O. tsutsugamushi genomic equivalent copies in tissues and sera. Furthermore, times to onset of the signs of infection are reported in this study. This study provides information useful for future research on this host-pathogen interaction and the associated vaccine efficacy trials.

  8. Karyotype reorganisation in the subtilis group of birch mice (Rodentia, Dipodidae, Sicista): unexpected taxonomic diversity within a limited distribution.

    Science.gov (United States)

    Kovalskaya, Y M; Aniskin, V M; Bogomolov, P L; Surov, A V; Tikhonov, I A; Tikhonova, G N; Robinson, T J; Volobouev, V T

    2011-01-01

    Conventional cytogenetic studies of Sicista subtilis and S. severtzovi (Dipodidae, Sicistinae), both attributable to the subtilis group of birch mice, revealed extensive karyotype diversity with 2n = 16-26 and NFa values of 26-46 indicating the overwhelming non-Robertsonian nature of chromosomal reorganization in these species. The numerical and structural chromosome variability was principally found in specimens located within a confined region of the East European (Russian) Plain. The approximately 135,000-km(2) area occurs in the vicinity of the Don River bend between 49°13'N/43°46'E and 51°32'N/36°16'E. The detection of cytotypes sharing similar 2n and NF values, but having morphologically distinct chromosomes, suggests that these may result from polymorphisms present both within recognized species and in cryptic taxa not hitherto described. We conducted a comprehensive, comparative chromosome banding analysis of 52 birch mice (21 localities) referable to the subtilis group and report the presence of 5 distinct karyotypes, each characterized by a combination of stable, variable, and partly overlapping 2n/NFa values. These karyotypes differed from each other by 10-29 structural chromosomal rearrangements (18.1 ± 6.3) that comprised Rb fusions/fissions (42.2%), pericentric inversions (31.1%), and tandem translocations (22.2%). The composition, and the high numbers of these chromosomal changes, is likely to provide an effective means of post-mating isolation, suggesting that taxonomic diversity within the subtilis group is larger than currently accepted. Additionally, we report the frequent fixation of tandem translocations in sample populations, one of which was found in a polymorphic state representing, as far as we are aware, the first case of an in statu nascendi tandem fusion in wild populations. Moreover, our data revealed that bi-armed chromosomes were involved in fusions detected in some of the subtilis taxa. In each instance, however, fusions were preceded by pericentric inversions that transform one or both bi-armed chromosomes into acrocentrics resulting in either centromere-telomere or Robertsonian translocations. Finally, a phylogenetic scenario inferred from a cladistic analysis of the chromosomal data suggests that the extensive karyotypic diversification within the subtilis group in the south-east region of the Russian Plain most likely results from fragmentation of a continuously distributed, ancestral population. It is thought that this occurred at the last glacial maximum (18,000-14,000 years B.P.), and that the process of isolation has been exacerbated by increasing human activity in the region in modern times.

  9. Karyotype diversity suggests that Laonastes aenigmamus (Laotian rock rat) (Rodentia, Diatomyidae) is a multi-specific genus.

    Science.gov (United States)

    Richard, Florence; Gerbault-Seureau, Michèle; Douangboupha, Bounneuang; Keovichit, Kham; Hugot, Jean-Pierre; Dutrillaux, Bernard

    2016-09-01

    Laonastes aenigmamus (Khanyou) is a recently described rodent species living in geographically separated limestone formations of the Khammuan Province in Lao PDR. Chromosomes of 21 specimens of L. aenigmamus were studied using chromosome banding as well as fluorescent in situ hybridization (FISH) techniques using human painting, telomere repeats, and 28S rDNA probes. Four different karyotypes were established. Study with human chromosome paints and FISH revealed that four large chromosomes were formed by multiple common tandem fusions, with persistence of some interstitial telomeres. The rearrangements separating the different karyotypes (I to IV) were also reconstructed. Various combinations of Robertsonian translocations or tandem fusions involving the same chromosomes differentiate these karyotypes. These rearrangements create a strong gametic barrier, which isolates specimens with karyotype II from the others. C-banding and FISH with telomere repeats also exhibit large and systematized differences between karyotype II and others. These data indicate an ancient reproductive separation and suggest that Laonastes is not a mono-specific genus.

  10. Trypanosoma cruzi: distinct patterns of infection in the sibling caviomorph rodent species Thrichomys apereoides laurentius and Thrichomys pachyurus (Rodentia, Echimyidae).

    Science.gov (United States)

    Roque, André Luiz Rodrigues; D'Andrea, Paulo Sérgio; de Andrade, Gisele Braziliano; Jansen, Ana Maria

    2005-09-01

    Thrichomys apereoides, a caviomorph rodent species common in a highly endemic area for Chagas disease in Brazil, may act as reservoir of the parasite. However, no information is available concerning its sibling species Thrichomys pachyurus, found in the Pantanal region, where Trypanosoma cruzi is found only in the enzootic cycle. We followed up the cross infection of these cryptic species with two isolates derived from naturally infected T. pachyurus and Thrichomys apereoides laurentius. No regional co-adaptation between Thrichomys species and the regional isolates were noticed. However, significant differences in the outcome of the infection were observed. T. a. laurentius was more resistant than T. pachyurus, as expressed by lower parasitemia and less histopathological damage. The routine biochemical markers used for laboratory rodents were unsuitable for follow up of infection in Thrichomys spp, since they did not correlate with the histopathological findings or allowed the kinetic follow-up of tissue colonization by the parasite.

  11. Genetic and morphological variability in South American rodent Oecomys (Sigmodontinae, Rodentia): evidence for a complex of species.

    Science.gov (United States)

    Rosa, C C; Flores, T; Pieczarka, J C; Rossi, R V; Sampaio, M I C; Rissino, J D; Amaral, P J S; Nagamachi, C Y

    2012-01-01

    The rodent genus Oecomys (Sigmodontinae) comprises ~16 species that inhabit tropical and subtropical forests in Central America and South America. In this study specimens of Oecomys paricola Thomas, 1904 from Belém and Marajó island, northern Brazil, were investigated using cytogenetic, molecular and morphological analyses. Three karyotypes were found, two from Belém (2n = 68, fundamental number (FN) = 72 and 2n = 70, FN = 76) and a third from Marajó island (2n = 70, FN = 72). No molecular or morphological differences were found between the individuals with differing cytotypes from Belém, but differences were evident between the individuals from Belém and Marajó island. Specimens from Belém city region may represent two cryptic species because two different karyotypes are present in the absence of significant differences in morphology and molecular characteristics. The Marajó island and Belém populations may represent distinct species that have been separated for some time, and are in the process of morphological and molecular differentiation as a consequence of reproductive isolation at the geographic and chromosomal levels. Thus, the results suggest that O. paricola may be a complex of species.

  12. Genetic differentiation in geographically close populations of the water rat Nectomys squamipes (Rodentia, Sigmodontinae from the Brazilian Atlantic Forest

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    Maroja L.S.

    2003-01-01

    Full Text Available We examined the genetic structure and the effects of a bottleneck in populations of the water rat Nectomys squamipes, a primary host of Schistosoma mansoni. Eight microsatellite loci were studied in 7 populations from the Sumidouro region of the Brazilian state of Rio de Janeiro. Our data, covering a four-year period during which a bottleneck occurred, revealed substantial variation (6-31 alleles per locus and high levels of both observed (0.718-0.789 and expected (0.748-0.832 heterozygosity. Most populations were in Hardy-Weinberg equilibrium without linkage disequilibrium between loci. Overall average genetic differentiation between populations (estimated with the F ST (q and R ST (r analogues was 0.037 for q and 0.060 for r. There was significant allelic and genotypic differentiation between populations, especially in pairwise comparisons that included the most geographically isolated population. Direct migration estimates showed a low rate of migration, indicating that infected N. squamipes populations had a limited ability to spread S. mansoni. When the pre- and post-bottleneck populations were compared there was no detectable reduction in heterozygosity or allele number, although a significant excess of heterozygosity was detected in the post-bottleneck population.

  13. Genetic and morphological variability in South American rodent Oecomys (Sigmodontinae, Rodentia): evidence for a complex of species

    Indian Academy of Sciences (India)

    C. C. Rosa; T. Flores; J. C. Pieczarka; R. V. Rossi; M. I. C. Sampaio; J. D. Rissino; P. J. S. Amaral; C. Y. Nagamachi

    2012-12-01

    The rodent genus Oecomys (Sigmodontinae) comprises ∼16 species that inhabit tropical and subtropical forests in Central America and South America. In this study specimens of Oecomys paricola Thomas, 1904 from Belém and Marajó island, northern Brazil, were investigated using cytogenetic, molecular and morphological analyses. Three karyotypes were found, two from Belém ($2n = 68$, fundamental number (FN) = 72 and $2n = 70$, FN = 76) and a third from Marajó island ($2n = 70$, FN = 72). No molecular or morphological differences were found between the individuals with differing cytotypes from Belém, but differences were evident between the individuals from Belém and Marajó island. Specimens from Belém city region may represent two cryptic species because two different karyotypes are present in the absence of significant differences in morphology and molecular characteristics. The Marajó island and Belém populations may represent distinct species that have been separated for some time, and are in the process of morphological and molecular differentiation as a consequence of reproductive isolation at the geographic and chromosomal levels. Thus, the results suggest that O. paricola may be a complex of species.

  14. Litomosoides anguyai n. sp. (Nematoda: Onchocercidae) from Oxymycterus misionalis (Rodentia: Muridae) in the rain forest of Misiones, Argentina.

    Science.gov (United States)

    Notarnicola, Juliana; Bain, Odile; Navone, Graciela

    2002-06-01

    A new species of Litomosoides is described from sigmodontine murids occurring in the rain forests of Misiones, Argentina. Litomosoides anguyai n. sp., a parasite of the abdominal cavity of Oxymycterus misionalis, belongs to the sigmodontis group and is closely related to L. legerae and L. oxymycteri. The new species is differentiated by the salient amphids, an asymmetrical annular thickening of the buccal capsule, by the arrangement of the head and tail papillae, and the shape and size of the microfilaria.

  15. Penial morphology in three species of Brazilian tuco-tucos, Ctenomys torquatus, C. minutus, and C. flamarioni (Rodentia: Ctenomyidae).

    Science.gov (United States)

    Rocha-Barbosa, O; Bernardo, J S L; Loguercio, M F C; Freitas, T R O; Santos-Mallet, J R; Bidau, C J

    2013-02-01

    The present study analyses the glans penis and baculum morphology of three Brazilian tuco-tucos, Ctenomys torquatus Lichtenstein, 1830, Ctenomys minutus Nehring, 1887 and Ctenomys flamarioni Travi, 1981, in order to identify possible variations and understand some more about this taxonomically complex group. We used fixed penis from 15 previously listed adult specimens. For a more detailed baculum analysis, the penis underwent dissection and diaphanisation, whereas to analyse the glans penis surface we used Scanning Electron Microscopy (SEM). Results showed striking differences in baculum morphology among the three species. While C. minutus have a particular V-shaped proximal baculum tip, C. flamarioni baculum is thin throughout the shaft with rounded proximal and distal tips. Ctenomys torquatus have a shorter and larger baculum, similar to what has previously been described for the species. Glans penis surface microstructure analyses also revealed inter-specific differences, with penial spines varying in shape, size and, especially density. Although C. torquatus has a relatively small penis, it has the largest penial spine density, which suggests a more complex penial ornamentation in this species.

  16. New data on occurrence of Demodex flagellurus (Acari, Demodecidae) - rarely recorded parasite from the house mouse Mus musculus (Rodentia, Muridae).

    Science.gov (United States)

    Izdebska, Joanna N; Rolbiecki, Leszek

    2015-01-01

    Demodex flagellurus Bukva, 1985 is one of two known demodecid mites of the house mouse Mus musculus Linnaeus, 1758, in which it is observed in genital area. Skin fragments of 30 house mice from various regions of Poland (residential buildings in Gdynia and Gdańsk, rural region in Wielkopolska-Kujawska Lowland) were examined. The mites were noted in 25.0% of the mice, with mean intensity of 48.0 and intensity range of 2-103. D. flagellurus demonstrated the differentiated occurrence in host populations.

  17. Demodex castoris sp. nov. (Acari: Demodecidae) parasitizing Castor fiber (Rodentia), and other parasitic arthropods associated with Castor spp.

    Science.gov (United States)

    Izdebska, Joanna N; Fryderyk, Sławomira; Rolbiecki, Leszek

    2016-02-11

    A new species of demodecid mite, Demodex castoris sp. nov. (Acari: Prostigmata: Demodecidae), is described based on adult stages from the skin of the nasal region of the Eurasian beaver Castor fiber Linnaeus, 1758, collected in Poland. This is the first detection of a representative demodecid mite in rodents of the suborder Castorimorpha and also represents the first detection of a skin mite in Eurasian beavers. The new species is a small skin mite (average 173 µm in length) characterized by sexual dimorphism related to body proportions. D. castoris sp. nov. was observed in 4 out of 6 beavers examined (66.6%), with a mean intensity of 10.8 and an intensity range of 2-23 ind. host(-1). This paper also contains a checklist of parasitic arthropods known from Castor spp.

  18. Napoleon Bonaparte and the fate of an Amazonian rat: new data on the taxonomy of Mesomys hispidus (Rodentia: Echimyidae).

    Science.gov (United States)

    Orlando, Ludovic; Mauffrey, Jean-François; Cuisin, Jacques; Patton, James L; Hänni, Catherine; Catzeflis, François

    2003-04-01

    The spiny rat Mesomys hispidus is one of many South American rodents that lack adequate taxonomic definition. The few sampled populations of this broadly distributed trans-Amazonian arboreal rat have come from widely separated regions and are typically highly divergent. The holotype was described in 1817 by A.-G. Desmarest, after Napoleon's army brought it to Paris following the plunder of Lisbon in 1808; however, the locality of origin has remained unknown. Here we examine the taxonomic status of this species by direct comparison of 50 extant individuals with the holotype at the morphometric and genetic levels, the latter based on 331 bp of the mitochondrial cytochrome b gene retrieved from a small skin fragment of the holotype with ancient DNA technology. Extensive sequence divergence is present among samples of M. hispidus collected from throughout its range, from French Guiana across Amazonia to Bolivia and Peru, with at least seven mitochondrial clades recognized (average divergence of 7.7% Kimura 2-parameter distance). Sequence from the holotype is, however, only weakly divergent from those of recent samples from French Guiana. Moreover, the holotype clusters with greater that 99% posterior probability with samples from this part of Amazonia in a discriminant analysis based on 22 cranial and dental measurements. Thus, we suggest that the holotype was originally obtained in eastern Amazonia north of the Amazon River, most likely in the Brazilian state of Amapá. Despite the high level of sequence diversity and marked morphological differences in size across the range of M. hispidus, we continue to regard this assemblage as a single species until additional samples and analyses suggest otherwise.

  19. Leishmania mexicana in Proechimys iheringi denigratus Moojen (Rodentia, Echimyidae in a region endemic for American cutaneous leishmaniasis

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    Air C. Barretto

    1985-12-01

    Full Text Available Three isolates of Leishmania were recovered from five of 27 specimens of the rodent Proechimys iheringi denigratus Moojen captured near Três Braços in the Atlantic Forest region of Bahia, Brazil. Two of these isolates were recovered from hamsters inoculated with a pooled triturate of liver, spleen and skin tissue from apparently healthy P. i. denigratus. The third isolate was recovered from a triturate of only skin tissue from another. Metastasis was observed in the inoculated hamsters, the parasites grew abundantly in artificial media and a typical suprapylarial pattern of infection in Lutzomyia longipalpis was produced indicating that the parasites belong to the Leishmania mexicana complex. All isolates reacted with Leishmania mexicana mexicana and Leishmania mexicana amazonensis monoclonal antibodies. The isoenzyme analysis differentiated these isolates from standard isolates of L. m. mexicana, L. m. amazonensis, L. m. aristedesi, L. m. pifanoi, L. m. garnhami and L. m. ssp.(Goiás-W. Barbosa. These isolates seem to be a subspecies of L. mexicana very closely related to L. m. amazonensis from which they differ by decreased electrophoretic mobility of GPI, PEP and ALAT. This is the first record of the isolation of a parasite of thegenus Leishmania in a rodent captured in the State of Bahia.

  20. Histopathology associated with angiostrongylosis in Akodon species (Rodentia: Sigmodontinae) from Sierra de la Ventana, Buenos Aires, Argentina.

    Science.gov (United States)

    Robles, María del Rosario; Perfumo, Carlos; Kinsella, John M; Navone, Graciela T

    2012-12-01

    Angiostrongylus is a metastrongylid nematode genus that includes species found in carnivores, rodents, and occasionally primates (including humans). About 100 species of wild sigmodontine rodents occur in Argentina, 16 of which are species of Akodon. The lungs of Akodon azarae and Akodon dolores from Sierra de la Ventana, Buenos Aires, Argentina, were examined, and 2 of 10 A. dolores specimens were positive for angiostrongylosis, showing macroscopic lesions of verminous pneumonia. Adults found were identified as Angiostrongylus morerai. Histopathology of the lungs revealed multiple nodules in the interstitium, alveoli, and vessels, resulting in interstitial fibrosis and the destruction of small capillaries and arterioles. Since extensive pathology in the lung was noted here from only 2 adults, it is probable that heavier infections may cause mortality in their hosts. This is the first record of this nematode species from A. dolores , expanding its geographic distribution to the southwest of Buenos Aires Province, and the first description of the histopathology of larval angiostrongylosis in a wild rodent from South America.

  1. New Details of the Eurasian Beaver’s, Castor Fiber (Rodentia, Castoridae, Expansion in the Lowland Part of Transcarpathia, Ukraine

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    Barkasi Z.

    2016-12-01

    Full Text Available The present paper contains information on a new beaver colony discovered in the Chornyi mochar tract, which is located in the lowland part of Transcarpathia (= Zakarpattia Region. This rodent species disappeared from the territory of Transcarpathia most likely in the 18th century. Its first reappearance was recorded in 2003. Since, the Eurasian beaver has demonstrated a rapid expansion, primarily along the main rivers. The discovered by us colony allows to suggest that the beaver is continuing its dispersal, entering far into the main river’s tributaries and other shallower water bodies. Consequently, we are witnessing not only the expansion of the species’ geographical range, but also the enlargement of the number of habitat types occupied by the animal. The possibilities and supposed consequences of the species’ further expansion within the tract are shown as well.

  2. Into Tibet: An Early Pliocene Dispersal of Fossil Zokor (Rodentia: Spalacidae) from Mongolian Plateau to the Hinterland of Tibetan Plateau.

    Science.gov (United States)

    Li, Qiang; Wang, Xiaoming

    2015-01-01

    This paper reports the fossil zokors (Myospalacinae) collected from the lower Pliocene (~4.4 Ma) of Zanda Basin, southwestern Tibet, which is the first record in the hinterland of Tibetan Plateau within the Himalayan Range. Materials include 29 isolated molars belonging to Prosiphneus eriksoni (Schlosser, 1924) by having characters including large size, highly fused roots, upper molars of orthomegodont type, m1 anterior cap small and centrally located, and first pair of m1 reentrants on opposing sides, high crowns, and high value of dentine tract parameters. Based on the cladistics analysis, all seven species of Prosiphneus and P. eriksoni of Zanda form a monophyletic clade. P. eriksoni from Zanda, on the other hand, is nearly the terminal taxon of this clade. The appearance of P. eriksoni in Zanda represents a significant dispersal in the early Pliocene from its center of origin in north China and Mongolian Plateau, possibly via the Hol Xil-Qiangtang hinterland in northern Tibet. The fast evolving zokors are highly adapted to open terrains at a time when regional climates had become increasingly drier in the desert zones north of Tibetan Plateau during the late Miocene to Pliocene. The occurrence of this zokor in Tibet thus suggests a rather open steppe environment. Based on fossils of large mammals, we have formulated an "out of Tibet" hypothesis that suggests earlier and more primitive large mammals from the Pliocene of Tibet giving rise to the Ice Age megafauna. However, fossil records for large mammals are still too poor to evaluate whether they have evolved from lineages endemic to the Tibetan Plateau or were immigrants from outside. The superior record of small mammals is in a better position to address this question. With relatively dense age intervals and numerous localities in much of northern Asia, fossil zokors provide the first example of an "into Tibet" scenario--earlier and more primitive taxa originated from outside of the Tibetan Plateau and the later the lineage became extinct in southwestern Tibet.

  3. A new species of Trichuris Roederer, 1761 (Nematoda: Trichuridae) from Heteromys gaumeri Allen & Chapman (Rodentia: Heteromyidae) in Yucatan, Mexico.

    Science.gov (United States)

    Panti-May, Jesús Alonso; Robles, María Del Rosario

    2016-09-01

    In Mexico, four species of Trichuris Roederer, 1761 have been recorded in wild rodents belonging to the family Heteromyidae. In the present paper, we describe a new species based on specimens collected from Heteromys gaumeri Allen & Chapman (Heteromyidae: Heteromyinae) in the tropical forests of the Yucatan Peninsula, Mexico. Trichuris silviae n. sp. can be differentiated from the congeners described in North and South American rodents by morphological and morphometric features, such as the possession of a wide spicular tube, a thicker proximal cloacal tube, a shorter distal cloacal tube and a cylindrical spicular sheath. This is the first description of a Trichuris spp. from heteromyid rodents in Mexico and the fourth in North America. Despite the broad distribution of Heteromys spp., few cases of Trichuris infection have been reported. Further studies are necessary to verify if the new species is present in other heteromyid rodents in order to increase our knowledge about its geographical and host distribution.

  4. Host cell/Orientia tsutsugamushi interactions: evolution and expression of syndecan-4 in Asian rodents (Rodentia, Muridae).

    Science.gov (United States)

    Badenhorst, Daleen; Tatard, Caroline; Suputtamongkol, Yupin; Robinson, Terence J; Dobigny, Gauthier

    2012-07-01

    Scrub typhus is an acute febrile zoonotic disease and worldwide more than a billion people may be at risk for infection. Orientia tsutsugamushi, the causative agent of scrub typhus, is an obligate intracellular bacterium. Rodents are reported to be the primary reservoir hosts of the disease and according to the most recent surveys, all species within the Rattus sensu lato complex of the tribe Rattini are carriers of scrub typhus. There is no evidence that any of mouse (Mus) species serves as the primary reservoir of the bacterium even when occurring in sympatry with wild infected rats. This contrast in the host/syndecan-4 interactions between Rattini and Asian Murini may be due to intrinsic (i.e., genetic) differences. Herein we compare the sequence and expression levels of syndecan-4 (the putative cell receptor of O. tsutsugamushi) between Rattini species that are known to be natural reservoirs for the typhus agents, and Murini species that are not. Although it was not possible to conclusively link the structural variations detected in syndecan-4 with carrier status in either Rattini and Murini, our findings indicate the absence of a strong Orientia-mediated selective regime acting on gene structure. In contrast, variable spleen-specific syndecan-4 expression levels show a strong correlation between under-expression of syndecan-4 in Murini and seropositive Rattini, compared to seronegative Rattini rodents. We postulate that two divergent responses may be at work in Murini and Rattini, both linked with differential expression of syndecan-4: (i) reduced syndecan-4 transcription in Murini decreases the likelihood that the host cells will become infected by the Orientia bacterium, while (ii) reduced syndecan-4 expression in seropositive Rattini limits the pathogenicity of Orientia and consequently improves the longevity of the rat hosts. These patterns may underpin the poor carrier status of wild mice on the one hand, and the effective role of wild rats as reservoir hosts on the other.

  5. Evolutionary and biological implications of dental mesial drift in rodents: the case of the Ctenodactylidae (Rodentia, Mammalia).

    Science.gov (United States)

    Gomes Rodrigues, Helder; Solé, Floréal; Charles, Cyril; Tafforeau, Paul; Vianey-Liaud, Monique; Viriot, Laurent

    2012-01-01

    Dental characters are importantly used for reconstructing the evolutionary history of mammals, because teeth represent the most abundant material available for the fossil species. However, the characteristics of dental renewal are presently poorly used, probably because dental formulae are frequently not properly established, whereas they could be of high interest for evolutionary and developmental issues. One of the oldest rodent families, the Ctenodactylidae, is intriguing in having longstanding disputed dental formulae. Here, we investigated 70 skulls among all extant ctenodactylid genera (Ctenodactylus, Felovia, Massoutiera and Pectinator) by using X-ray conventional and synchrotron microtomography in order to solve and discuss these dental issues. Our study clearly indicates that Massoutiera, Felovia and Ctenodactylus differ from Pectinator not only by a more derived dentition, but also by a more derived eruptive sequence. In addition to molars, their dentition only includes the fourth deciduous premolars, and no longer bears permanent premolars, conversely to Pectinator. Moreover, we found that these premolars are lost during adulthood, because of mesial drift of molars. Mesial drift is a striking mechanism involving migration of teeth allowed by both bone remodeling and dental resorption. This dental innovation is to date poorly known in rodents, since it is only the second report described. Interestingly, we noted that dental drift in rodents is always associated with high-crowned teeth favoring molar size enlargement. It can thus represent another adaptation to withstand high wear, inasmuch as these rodents inhabit desert environments where dust is abundant. A more accurate study of mesial drift in rodents would be very promising from evolutionary, biological and orthodontic points of view.

  6. First record of Mylagaulid rodents (Rodentia, Mammalia) from the Miocene of Eastern Siberia (Olkhon Island, Baikal Lake, Irkutsk Region, Russia).

    Science.gov (United States)

    Tesakov, A S; Lopatin, A V

    2015-01-01

    A new genus and species of rodent, Lamugaulus olkhonensis, belonging to the subfamily Promylagaulinae of the family Mylagaulidae, is described on the basis of isolated teeth from the Khalagay Formation of the Lower Miocene Tagay locality (Olkhon island, Lake Baikal, Irkutsk Region). This is the first record of mylagaulids in Eastern Siberia, significantly expanding the data on the distribution of this mainly North American group of rodents in Asia and showing its presence outside the Central Asian arid zone.

  7. [Morphological diversity in the postnatal skull development in representatives of two families of rodents (Spalacidae, Castoridae, Rodentia)].

    Science.gov (United States)

    Puzachenko, A Iu; Korablev, N P

    2014-01-01

    This is the first study to describe the results of measurement of three information parameters of morphological diversity (entropy, the measure of organization, and the Kullback-Leibler divergence) in the course of postnatal development of the skull in the populations of two rodent species (greater mole rat (Spalax microphthalmus Guld.) and Eurasian beaver (Castor fiber (L.)). The terms "morphosystem" and "morphological space" and its structure are introduced. Within the framework of the developed approach, "morphological diversity" is considered as a variable associated with the morphological space structure. Testing the hypothesis of the dominance of self-organization processes and an increase in the organization of the morphological diversity of the skull in the course ofontogeny showed its inconsistency. The morphosystem of the skull of the studied species undergoes transitions between more organized and less organized states, periodically approaching and departing from the "steady state." Such dynamics characterizes the morphosystem of the skull as a dynamic and nonlinear system.

  8. Phylogenetic relationships in the Niviventer-Chiromyscus complex (Rodentia, Muridae inferred from molecular data, with description of a new species

    Directory of Open Access Journals (Sweden)

    Alexander Balakirev

    2014-11-01

    Full Text Available Based on molecular data for mitochondrial (Cyt b, COI and nuclear (IRBP, GHR genes, and morphological examinations of museum specimens, we examined diversity, species boundaries, and relationships within and between the murine genera Chiromyscus and Niviventer. Phylogenetic patterns recovered demonstrate that Niviventer sensu lato is not monophyletic but instead includes Chiromyscus chiropus, the only previously recognized species of Chiropus. To maintain the genera Niviventer and Chiropus as monophyletic lineages, the scope and definition of the genus Chiromyscus is revised to include at least three distinct species: Chiromyscus chiropus (the type species of Chiromyscus, C. langbianis (previously regarded as a species of Niviventer, and a new species, described in this paper under the name C. thomasi sp. n.

  9. Preliminary study on the distribution pattern of small mammals in Ningxia Helan Mountain Nature Reserve%宁夏贺兰山自然保护区小兽格局分布的初步研究

    Institute of Scientific and Technical Information of China (English)

    吴建华; 郑艳娟; 雷静; 白学礼; 张涛; 张家训

    2015-01-01

    目的:掌握贺兰山自然保护区小兽类动物种群格局与区系分布,为林业部门和旅游业预防鼠害及鼠传疾病提供科学依据以及为小兽类动物研究提供基础生物学资料。方法于2012年10月至2013年10月,在贺兰山东麓滚钟口和苏峪口两个区域的4个有林垂直带,采集小兽类标本,结合以前文献进行综合整理,建立小兽类动物种群分布信息数据库,运用Excel 2003软件和动物群落相似度进行分析。结果贺兰山自然保护区共有小兽类动物43种,隶属6目10科33属。分析表明,啮齿目仓鼠科、鼠科和跳鼠科共计26种,是贺兰山自然保护区小兽类动物的基本类群,北社鼠为优势种。在贺兰山的43种小兽类动物中,属古北界的30种,广布的12种,东洋界1种。结论通过调查基本掌握了贺兰山自然保护区部分地区小兽类动物的种群格局与区系分布,也为该地区进一步研究鼠传疾病提供了依据。%Objective In order to better grasp the Helan Mountain (Mts. Helan Shan region) Nature Reserve of small mammal animal population pattern and fauna distribution, and provide scientific basis for mice and rats transmit disease prevention of forestry department and the tourism, also provide the basic data for the study of biology of small mammals. Methods In 2012 October-2013 October on the activity peak in Helan Mountain donglu Gunzhongkou and Suyukou two region of 4 forest belt, acquisition of small mammal specimens, combined with the comprehensive arrangement of previous literature, a small mammal animal population distribution information data in the database, using Excel 2003 and animal community similarity analysis. Results The nature reserve has a total of 43 species of small mammals, belonging to 6 orders, 10 families and 32 genera. Analysis shows that, Rodentia, Cricetidae, Muridae and jerboa total 26 species, is the fundamental group of small mammals area of Helan

  10. Trichospirura aethiopica n. sp. (Nematoda: Rhabdochonidae from Malacomys longipes (Rodentia: Muridae in Gabon, first record of the genus in the Ethiopian Realm

    Directory of Open Access Journals (Sweden)

    Bain Odile

    2013-01-01

    Full Text Available Trichospirura aethiopica n. sp. is described from unidentified tubular structures (pancreatic ducts? near the stomach of the murid Malacomys longipes Milne-Edwards, 1877 in Gabon. The extremely long and narrow buccal capsule, posterior position of the vulva, unequal spicules and absence of caudal alae readily identified the specimens as belonging to Trichospirura Smith & Chitwood, 1967, but a combination of several characters distinguished them from the described species in this genus. Males of the new species are characterized by the absence of precloacal papillae, the presence of four pairs of postcloacal papillae and a left spicule length of 165–200 μm. With only five nominal and one unnamed species, the host range of Trichospirura extends into the Neotropical, Indo-Malayan and Ethiopian Realms and comprises three classes of vertebrates, Amphibia, Reptilia and Mammalia, suggesting a larger species diversity than that currently recorded. Detection is difficult as predilection sites are often outside the gut lumen. It was noted that, irrespective of their geographic origin, species from mammals share certain characters (shorter left spicule and absence of precloacal papillae that oppose them to those from amphibians and reptiles. A hypothesis for the origin of Trichospirura in mammals through a remote host-switching event in tupaiids in southern Asia, likely facilitated by the intermediate hosts, and for their subsequent migration to the Ethiopian and finally Neotropical Realm is proposed. Regarding the two species from anurans and saurians in the Antilles, one or two host-switching events are considered equally possible, based on morphological characters.

  11. Evidence for eight tandem and five centric fusions in the evolution of the karyotype of Aethomys namaquensis A. Smith (Rodentia: Muridae).

    Science.gov (United States)

    Baker, R J; Qumsiyeh, M B; Rautenbach, I L

    1988-06-30

    G- and C-banded chromosomes of Aethomys namaquensis (2n = 24), A. chrysophilus (2n = 44), and Praomys coucha (2n = 36) are compared and contrasted with published material on Australian Muridae and North American Sigmodontidae. Direction and types of chromosomal rearrangements are established using cladistic methodology. An acrocentric morphology for chromosomes 5, 14, 15 and 20 (numbering system from Peromyscus) are proposed as primitive for the common ancestor of the Muridae and Sigmodontidae rodent lineages. Reduced diploid number of Aethomys namaquensis is derived by eight tandem and five centric fusions since divergence from the common ancestor with A. chrysophilus. The two species of Aethomys share one derived metacentric chromosome that distinguishes them from Praomys. Praomys has unique chromosomes which can be derived from the proposed primitive condition by five centric fusions and five pericentric inversions. It is concluded that karyotypic orthoselection for tandem and centric fusions is best explained by cellular or biochemical mechanisms rather than variation in population characteristics.

  12. Demography, reproductive biology and diet of the bushveld gerbil Tatera leucogaster (Rodentia: Gerbillinae) in the Lake Rukwa valley, southwestern Tanzania

    DEFF Research Database (Denmark)

    Odhiambo, Richgard O.; Makundi, Rhodes H.; Leirs, Herwig;

    2008-01-01

    Seasonal abundance, reproductive biology and feeding ecology of the bushveld gerbil Tatera leucogaster (Peters, 1852) were investigated in small-scale maize field-fallow land mosaics in south-western Tanzania. The gerbils were collected over a 2-year period using Sherman live and Victor hold-fast...

  13. A study on ecology, morphology and morphometry of Acomys dimidiatus Cretzschmar, 1826 (Rodentia: Muridae in Geno sanctuary and Minab County, Hormozgan Province, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Ashrafzadeh

    2012-03-01

    Full Text Available In the present study, two populations of Acomys dimidiatus from different locations of Hormozgan Province (Geno sanctuary and Minab County were compared according to their morphometric, morphological and ecological characteristics. Fifty eight specimens of adult A. dimidiatus were collected by live traps (Sherman traps, Havahart traps and locally made traps from these regions. We caught the rodents from the height ranging from 1500 meters. According to our field observations, the studied species was mostly nocturnal. At first, five external and fifteen cranial- dental characters were measured, then ratios of measured characters to head and body length were calculated. The normality of data was analyzed by Kolmogorov- Smironov test. Descriptive statistics were calculated for characters and ratios. The results showed that the average of 14 out of 20 characters in Minab specimens was greater than Geno specimens. Also, the average of all of the ratios (20 ratios in Minab specimens was greater than that of Geno region. Independent Sample T-Test was used to test the statistical significance between length and ratios. The results indicated that there were significance differences in five out of twenty characters and nine out of twenty ratios in two regions(P<0.05. In addition, MANOVA test revealed significant differences among the studied populations (P<0.05. Also, intraspecific variations were assessed with the principal components analysis (PCA. The first two principal components accounted for more than 60% of the total variance and the species were fairly well separated by them.

  14. Small mammals (Chiroptera, Didelphimorphia, and Rodentia) from Jaíba, middle Rio São Francisco, northern Minas Gerais State, Brazil

    OpenAIRE

    Nogueira,Marcelo Rodrigues; Pol,André; Pessôa,Leila Maria; Oliveira,João Alves de; Peracchi,Adriano Lúcio

    2015-01-01

    We report the results of small mammals inventories conducted in the region of Jaíba, northern Minas Gerais state, southeastern Brazil, from 1990 to 1995. This region is located in the southern limit of the Caatinga biome, and harbors a unique set of natural ecosystems and extensive agricultural areas. With a total effort of 2964 trap-nights and 44 net sessions, we captured 893 small mammals from 46 species, including four marsupials, 13 rodents, and 29 bats. We report on species that are...

  15. Stress-associated radiation effects in pygmy wood mouse Apodemus uralensis (Muridae, Rodentia) populations from the East-Urals Radioactive Trace.

    Science.gov (United States)

    Orekhova, Natal'ya A; Modorov, Makar V

    2016-09-01

    This work is based on the comparative analysis of data obtained in the course of monitoring pygmy wood mouse populations (Apodemus uralensis Pallas, 1811) in the East-Urals Radioactive Trace (EURT) area and background territories. The effect of population size and its interaction with the radioactivity on biochemical parameters in the spleen and adrenal glands was studied. The concentrations of total lipids, proteins, DNA and RNA, activity of glucose-6-phosphate isomerase and catalase as well as the level of lipid peroxidation (LPO) were evaluated. The functional-metabolic shifts seen with large population sizes were characterized by delipidisation of adrenocortical cells, increased LPO as the main mechanism for steroidogenesis, growth of the protein components of the adrenal glands to maintain their hyperfunction, as well as immunosuppression associated with the restriction of carbohydrates providing splenocytes, reduction of DNA synthesis, and the development of a pro-/antioxidant imbalance. Reactivity of the neuroendocrine and hematopoietic systems of animals experiencing a high population density was higher in the EURT zone compared with the reference group. This difference can be explained by the additional stress from the chronic radiation exposure. The level of LPO, catalase activity, and DNA/protein ratio in the spleen and the total protein content in the adrenal glands were the most sensitive to the interaction of population size and radiation exposure. The harmful effect (distress) of the interaction of non-radiation and radiation factors can manifest when there is a population abundance above 30 ind./100 trap-day and a radiation burden which exceeds the lower boundary of the Derived Consideration Reference Levels, which is above 0.1 mGy/day.

  16. Short-term effects of avian predation variation on population size and local survival of the multimammate rat, Mastomys natalensis (Rodentia, Muridae)

    DEFF Research Database (Denmark)

    Gulck, T. van; Stocks, R.; Verhagen, Ron;

    1998-01-01

    was not true but this might be due to the small size of the experimental fields. Analysis of weekly collected raptor pellets, over a 15 month period, showed an overrepresentation of M. natalensis as prey and a strong positive correlation between the density of M. natalensis and the avian predation intensity....

  17. Toxicological Evaluation of Essential Oil From the Leaves of Croton argyrophyllus (Euphorbiaceae) on Aedes aegypti (Diptera: Culicidae) and Mus musculus (Rodentia: Muridae).

    Science.gov (United States)

    Cruz, R C D; Silva, S L C E; Souza, I A; Gualberto, S A; Carvalho, K S; Santos, F R; Carvalho, M G

    2017-01-27

    Plant-derived essential oils can be used as insecticides for vector control. However, to establish their safety, it is necessary to perform toxicological studies. Herein, we evaluated the chemical composition and insecticidal activity of the essential oil from the leaves of Croton argyrophyllus on the third- and fourth-instar larvae and adult Aedes aegypti (L., 1762). We also evaluated the acute toxicity of the essential oil in adult female Mus musculus The lethal concentration 50 (LC50) and 90 (LC90) of C. argyrophyllus essential oil on larvae of Ae. aegypti were 0.31 and 0.70 mg ml(-1), respectively, and 5.92 and 8.94 mg ml(-1), respectively, on Ae. aegypti adults. The major components of the essential oil were spathulenol (22.80%), (E)-caryophyllene (15.41%), α-pinene (14.07%), and bicyclogermacrene (10.43%). It also displayed acute toxicity in adults of Mus musculus; the intraperitoneal and oral lethal dose 50 (LD50) were 2,000 mg kg(-1) and 2,500 mg kg(-1), respectively. The results showed that the essential oil from C. argyrophyllus leaves has insecticidal activity on Ae. aegypti larvae and adults at an average lethal concentration below the median lethal dose needed to cause acute toxicity in the common mouse.

  18. Lineage-specific responses of tooth shape in murine rodents (murinae, rodentia to late Miocene dietary change in the Siwaliks of Pakistan.

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    Yuri Kimura

    Full Text Available Past ecological responses of mammals to climate change are recognized in the fossil record by adaptive significance of morphological variations. To understand the role of dietary behavior on functional adaptations of dental morphology in rodent evolution, we examine evolutionary change of tooth shape in late Miocene Siwalik murine rodents, which experienced a dietary shift toward C4 diets during late Miocene ecological change indicated by carbon isotopic evidence. Geometric morphometric analysis in the outline of upper first molars captures dichotomous lineages of Siwalik murines, in agreement with phylogenetic hypotheses of previous studies (two distinct clades: the Karnimata and Progonomys clades, and indicates lineage-specific functional responses to mechanical properties of their diets. Tooth shapes of the two clades are similar at their sympatric origin but deviate from each other with decreasing overlap through time. Shape change in the Karnimata clade is associated with greater efficiency of propalinal chewing for tough diets than in the Progonomys clade. Larger body mass in Karnimata may be related to exploitation of lower-quality food items, such as grasses, than in smaller-bodied Progonomys. The functional and ecophysiological aspects of Karnimata exploiting C4 grasses are concordant with their isotopic dietary preference relative to Progonomys. Lineage-specific selection was differentially greater in Karnimata, and a faster rate of shape change toward derived Karnimata facilitated inclusion of C4 grasses in the diet. Sympatric speciation in these clades is most plausibly explained by interspecific competition on resource utilization between the two, based on comparisons of our results with the carbon isotope data. Interspecific competition with Karnimata may have suppressed morphological innovation of the Progonomys clade. Pairwise analyses of morphological and carbon isotope data can uncover ecological causes of sympatric speciation and define functional adaptations of teeth to resources.

  19. Contribution to the systematics and zoogeography of the East-African Acomys spinosissimus Peters 1852 species complex and the description of two new species (Rodentia: Muridae)

    DEFF Research Database (Denmark)

    Verheyen, W.; Hulselmans, J.; Wendelen, W.

    2011-01-01

    We revised the taxonomic status of the putative Acomys spinosissimus complex based on the comparative study of specimen collections from Tanzania, Zambia, Zimbabwe, Mozambique, DR Congo and South Africa, by means of analysis of external morphology, craniometry, enzymes, mitochondrial DNA sequences....... transvaalensis) occurs further to the South (i.e. northern limit seemingly just north of the Limpopo River). The investigated populations north of the Zambezi River are morphologically and genetically distinct from A. spinosissimus and A. selousi. Based on this evidence, we described Acomys muzei sp. nov....... and Acomys ngurui sp. nov., each one occurring separately along one side of the Eastern Arc Mountains. Finally, we lacked sufficient information to describe a third new species from the area north of the Zambesi River...

  20. The phylogenetic position of "Acomyinae" (Rodentia, Mammalia) as sister group of a Murinae plus Gerbillinae clade : Evidence from the nuclear ribonuclease gene

    NARCIS (Netherlands)

    Dubois, JYF; Catzeflis, FM; Beintema, JJ

    1999-01-01

    The phylogenetic relationships of Acomys and Uranomys within Muridae were investigated using nuclear pancreatic ribonuclease A gene sequences. The various kinds of substitutions in the data matrix (15 taxa x 375 nucleotides) were examined for saturation, in order to apply a weighted parsimony approa

  1. Multiple interstitial ribosomal sites (NORs in the Brazilian squirrel Sciurus aestuans ingrami (Rodentia, Sciuridae with 2n = 40: an overview of Sciurus cytogenetics

    Directory of Open Access Journals (Sweden)

    Valéria Fagundes

    2003-01-01

    Full Text Available This is the first time the karyotype of the Brazilian squirrel Sciurusaestuans ingrami, with 2n = 40, is described. The karyotype of this species comprises 18 pairs of biarmed and one minute pair of acrocentric autosomes, a medium-sized submetacentric X and a medium-sized acrocentric Y. Four pairs have an interstitial secondary constriction, co-located with nucleolar organizer regions (NORs, identified by silver-staining technique and fluorescent in situ hybridization (FISH with ribosomal 18S/28S probes. The occurrence of multiple interstitial NORs is rare in rodents, and this is one of the few examples, identified by a molecular cytogenetics approach.

  2. Note on breeding and parental care behaviours of albino Hoary-bellied Squirrel Callosciurus pygerythrus (Rodentia: Sciuridae in Sibsagar District of Assam, India

    Directory of Open Access Journals (Sweden)

    G. Kalita

    2009-06-01

    Full Text Available A few individuals of albino Horay-bellied Squirrels along with normal gray individuals of Callosciurus pygerythrus have been observed in Sibsagar district of Assam, India. One albino female was studied in captivity. This paper presents our observations on the breeding behaviour and the parental care exhibited by the albino squirrel in captivity. The squirrel bred twice in captivity with a normal male of the same species. In both the periods, a single male baby with normal coat colour developed. Oral dose of vitamin E has been found helpful in the breeding of the studied squirrel species. The mother squirrel exhibited parental care by carrying her baby using her mouth, to a safer place during danger. However, the observed phenomenon is unlike that of the cat species. Some of the habitat ecology and feeding habits of the albino squirrels have also been studied, both in natural and in captive conditions.

  3. Panic-like defensive behavior but not fear-induced antinociception is differently organized by dorsomedial and posterior hypothalamic nuclei of Rattus norvegicus (Rodentia, Muridae

    Directory of Open Access Journals (Sweden)

    A.F. Biagioni

    2012-04-01

    Full Text Available The hypothalamus is a forebrain structure critically involved in the organization of defensive responses to aversive stimuli. Gamma-aminobutyric acid (GABAergic dysfunction in dorsomedial and posterior hypothalamic nuclei is implicated in the origin of panic-like defensive behavior, as well as in pain modulation. The present study was conducted to test the difference between these two hypothalamic nuclei regarding defensive and antinociceptive mechanisms. Thus, the GABA A antagonist bicuculline (40 ng/0.2 µL or saline (0.9% NaCl was microinjected into the dorsomedial or posterior hypothalamus in independent groups. Innate fear-induced responses characterized by defensive attention, defensive immobility and elaborate escape behavior were evoked by hypothalamic blockade of GABA A receptors. Fear-induced defensive behavior organized by the posterior hypothalamus was more intense than that organized by dorsomedial hypothalamic nuclei. Escape behavior elicited by GABA A receptor blockade in both the dorsomedial and posterior hypothalamus was followed by an increase in nociceptive threshold. Interestingly, there was no difference in the intensity or in the duration of fear-induced antinociception shown by each hypothalamic division presently investigated. The present study showed that GABAergic dysfunction in nuclei of both the dorsomedial and posterior hypothalamus elicit panic attack-like defensive responses followed by fear-induced antinociception, although the innate fear-induced behavior originates differently in the posterior hypothalamus in comparison to the activity of medial hypothalamic subdivisions.

  4. Panic-like defensive behavior but not fear-induced antinociception is differently organized by dorsomedial and posterior hypothalamic nuclei of Rattus norvegicus (Rodentia, Muridae)

    Science.gov (United States)

    Biagioni, A.F.; Silva, J.A.; Coimbra, N.C.

    2012-01-01

    The hypothalamus is a forebrain structure critically involved in the organization of defensive responses to aversive stimuli. Gamma-aminobutyric acid (GABA)ergic dysfunction in dorsomedial and posterior hypothalamic nuclei is implicated in the origin of panic-like defensive behavior, as well as in pain modulation. The present study was conducted to test the difference between these two hypothalamic nuclei regarding defensive and antinociceptive mechanisms. Thus, the GABAA antagonist bicuculline (40 ng/0.2 µL) or saline (0.9% NaCl) was microinjected into the dorsomedial or posterior hypothalamus in independent groups. Innate fear-induced responses characterized by defensive attention, defensive immobility and elaborate escape behavior were evoked by hypothalamic blockade of GABAA receptors. Fear-induced defensive behavior organized by the posterior hypothalamus was more intense than that organized by dorsomedial hypothalamic nuclei. Escape behavior elicited by GABAA receptor blockade in both the dorsomedial and posterior hypothalamus was followed by an increase in nociceptive threshold. Interestingly, there was no difference in the intensity or in the duration of fear-induced antinociception shown by each hypothalamic division presently investigated. The present study showed that GABAergic dysfunction in nuclei of both the dorsomedial and posterior hypothalamus elicit panic attack-like defensive responses followed by fear-induced antinociception, although the innate fear-induced behavior originates differently in the posterior hypothalamus in comparison to the activity of medial hypothalamic subdivisions. PMID:22437484

  5. Intense genomic reorganization in the genus Oecomys (Rodentia, Sigmodontinae: comparison between DNA barcoding and mapping of repetitive elements in three species of the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Renan Gabriel Gomes Junior

    2016-09-01

    Full Text Available Oecomys Thomas, 1906 is one of the most diverse and widely distributed genera within the tribe Oryzomyini. At least sixteen species in this genus have been described to date, but it is believed this genus contains undescribed species. Morphological, molecular and cytogenetic study has revealed an uncertain taxonomic status for several Oecomys species, suggesting the presence of a complex of species. The present work had the goal of contributing to the genetic characterization of the genus Oecomys in the Brazilian Amazon. Thirty specimens were collected from four locations in the Brazilian Amazon and three nominal species recognized: Oecomys auyantepui (Tate, 1939, O. bicolor (Tomes, 1860 and O. rutilus (Anthony, 1921. COI sequence analysis grouped O. auyantepui, O. bicolor and O. rutilus specimens into one, three and two clades, respectively, which is consistent with their geographic distribution. Cytogenetic data for O. auyantepui revealed the sympatric occurrence of two different diploid numbers, 2n=64/NFa=110 and 2n=66/NFa=114, suggesting polymorphism while O. bicolor exhibited 2n=80/NFa=142 and O. rutilus 2n=54/NFa=90. The distribution of constitutive heterochromatin followed a species-specific pattern. Interspecific variation was evident in the chromosomal location and number of 18S rDNA loci. However, not all loci showed signs of activity. All three species displayed a similar pattern for 5S rDNA, with only one pair carrying this locus. Interstitial telomeric sites were found only in O. auyantepui. The data presented in this work reinforce intra- and interspecific variations observed in the diploid number of Oecomys species and indicate that chromosomal rearrangements have led to the appearance of different diploid numbers and karyotypic formulas.

  6. Cadmium and lead concentrations in Skrjabinotaenia lobata (Cestoda: Catenotaeniidae) and in its host, Apodemus sylvaticus (Rodentia: Muridae) in the urban dumping site of Garraf (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Torres, Jordi [Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitaries, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII, sn, 08028 Barcelona (Spain)]. E-mail: jtorres@ub.edu; Peig, Jordi [Departament de Biologia Animal (Vertebrats), Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, 08028 Barcelona (Spain); Eira, Catarina [Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitaries, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII, sn, 08028 Barcelona (Spain); Borras, Miquel [Unitat de Toxicologia Experimental i Ecotoxicologia. Parc Cientific de Barcelona, C/Josep Samitier 1-5, 08028 Barcelona (Spain)

    2006-09-15

    The present study evaluates the parasitological model constituted by the wood mouse (Apodemus sylvaticus) and its intestinal cestode (Skrjabinotaenia lobata) as a potential bioindicator of Cd and Pb in the urban dumping site of Garraf near the city of Barcelona (Spain) and in Begues (reference site). Tissues and respective S. lobata specimens of 38 wood mice captured in Garraf and Begues were analyzed for Cd and Pb by means of ICP-MS. Higher cadmium levels in S. lobata were found only in respect to the muscular levels of their hosts. Nevertheless, lead levels were 8.5-, 53.2- and 81.4-fold higher in S. lobata than kidney, liver and muscle levels of A. sylvaticus from Garraf, respectively. Thus, the proposed model seems to be a promising bioindicator to evaluate environmental lead exposure in terrestrial habitats. In addition, all available data on lead bioaccumulation by cestode parasites of terrestrial mammals are generally discussed. - The parasitological model S. lobata/A. sylvaticus presents suitable features to be used as a bioindicator of lead pollution in terrestrial habitats.

  7. Estudio preliminar del esqueleto postcraneal del Muscardinus cyclopeus Agustí, Moyà-Solà & Pons-Moyà, 1982 (Mammalia, Rodentia, Myoxidae

    Directory of Open Access Journals (Sweden)

    Quintana Cardona, J.

    2015-06-01

    Full Text Available For the first time, the partial skeleton of the Pliocene Muscardinus cyclopeus is described from Punta Nati-3, located in the northwest of the municipality of Ciutadella de Menorca (Balearic Islands, western Mediterranean. Based on bone parameters it is shown that the size of Muscardinus cyclopeus is on overage 69% higher than that of Muscardinus avellanarius. The main features that distinguish M. cyclopeus from M. avellanarius are, among others: the relatively wider diameter of the proximal epiphysis of the ulna; the relatively shorter olecranon; the less marked concavity in the fovea of the proximal epiphysis of the radius; the relatively shorter ilium; the more symmetrical epicondyles of the distal femoral epiphysis; the relatively higher lateral epicondyle dorsoventrally, with a very flat ventral surface; and the relatively narrower tibia transversely. As a species evolved in an insular context, it is still very difficult to discern which of these characters are primitive and which are derived.Se describe, por primera vez, parte del esqueleto del muscardino gigante del Plioceno de Menorca, procedente del yacimiento 3 de Punta Nati, situado al noroeste del término municipal de Ciutadella de Menorca (Islas Baleares, Mediterráneo occidental. A partir de los parámetros óseos se ha podido constatar que Muscardinus cyclopeus muestra, de media, un tamaño un 69% superior al de Muscardinus avellanarius (Linnaeus, 1758. Entre las principales características óseas que diferencian M. cyclopeus de M. avellanarius cabe destacar, entre otras, el diámetro proporcionalmente más ancho de la epífisis proximal de la ulna, el olecranon proporcionalmente más corto, la fóvea de la epífisis proximal del radio con una concavidad menos marcada, el ilium proporcionalmente más corto, los epicóndilos de la epífisis distal del fémur más simétricos, el epicóndilo lateral proporcionalmente más alto en sentido dorso-ventral, con la superficie ventral muy aplanada y la tibia proporcionalmente más estrecha en sentido transversal. Al tratarse de una especie evolucionada en un contexto insular, resulta difícil dilucidar cuales son caracteres primitivos y caracteres derivados.

  8. Cranial phenotypic variation in Meriones crassus and M. libycus (Rodentia, Gerbillinae, and a morphological divergence in M. crassus from the Iranian Plateau and Mesopotamia (Western Zagros Mountains

    Directory of Open Access Journals (Sweden)

    Fatemeh Tabatabaei Yazdi

    2014-06-01

    Full Text Available Jirds (genus Meriones are a diverse group of rodents, with a wide distribution range in Iran. Sundevall’s jird (Meriones crassus Sundevall, 1842 is one such species that shows a disjunct distribution, found on the Iranian Plateau and Western Zagros Mountains. Morphological differences observed between these two populations, however, lack quantitative support. Morphological differences between geographical populations of Meriones crassus were analysed and compared with those of the sympatric M. libycus. Similarities in the cranial morphology of these species were found, e.g. in a relatively large and inflated bulla. A two-dimensional geometric morphometric analysis was done on the skull of 275 M. crassus and 220 M. libycus from more than 70 different localities in their distribution range. Results confirm cranial differences between specimens of M. crassus from the Western Zagros and those from Africa and Arabia, mainly at the level of the relative size of the tympanic bulla, that were significantly correlated with the annual rainfall and elevation. Moreover, the study supports the hypothesis that the Western Zagros specimens are both a geographically and phenotypically distinct group compared to the other Iranian M. crassus specimens, suggesting that the former might be a distinct species.

  9. Mitochondrial DNA diversity and population structure of a forest-dependent rodent, Praomys taitae (Rodentia: Muridae) Heller 1911, in the fragmented forest patches of Taita Hills, Kenya

    DEFF Research Database (Denmark)

    Nyakaana, S.; Tumusiime, C.; Oguge, N.;

    2008-01-01

    The population genetic structure of the forest-dependent rodent, Praomys taitae, sampled from nine indigenous forest fragments sampled from nine indigenous forest fragments distributed over three ranges of the Taita Hills in Kenya, was determined using mitochondrial DNA (mtDNA) control region...

  10. Development of nine new microsatellite loci for the American beaver, Castor canadensis (Rodentia: Castoridae), and cross-species amplification in the European beaver, Castor fiber

    Science.gov (United States)

    Pelz-Serrano, K.; Munguia-Vega, A.; Piaggio, A.J.; Neubaum, M.; Munclinger, P.; PArtl, A.; van Riper, Charles; Culver, M.

    2009-01-01

    We developed nine new nuclear dinucleotide microsatellite loci for Castor canadensis. All loci were polymorphic, except for one. The number of alleles ranged from two to four and from five to 12 in populations from Arizona and Wisconsin, respectively. Average heterozygosity ranged from 0.13 to 0.86 per locus. Since cross-species amplification in Castor fiber was successful only in four loci, we tested also nine recently published C. canadensis loci in the Eurasian species. Eight of the published loci amplified; however, three were monomorphic. The number of alleles was lower in C. fiber than in C. canadensis at all loci tested. ?? 2009 Blackwell Publishing Ltd.

  11. Bartonella jaculi sp. nov., Bartonella callosciuri sp. nov., Bartonella pachyuromydis sp. nov. and Bartonella acomydis sp. nov., isolated from wild Rodentia.

    Science.gov (United States)

    Sato, Shingo; Kabeya, Hidenori; Fujinaga, Yuta; Inoue, Kai; Une, Yumi; Yoshikawa, Yasuhiro; Maruyama, Soichi

    2013-05-01

    Four novel strains of members of the genus Bartonella, OY2-1(T), BR11-1(T), FN15-2(T) and KS2-1(T), were isolated from the blood of wild-captured greater Egyptian jerboa (Jaculus orientalis), plantain squirrel (Callosciurus notatus), fat-tailed gerbil (Pachyuromys duprasi) and golden spiny mouse (Acomys russatus). All the animals were imported to Japan as pets from Egypt, Thailand and the Netherlands. The phenotypic characterization (growth conditions, incubation periods, biochemical properties and cell morphologies), DNA G+C contents (37.4 mol% for strain OY2-1(T), 35.5 mol% for strain BR11-1(T), 35.7 mol% for strain FN15-2(T) and 37.2 mol% for strain KS2-1(T)), and sequence analyses of the 16S rRNA genes indicated that those strains belong to the genus Bartonella. Sequence comparisons of gltA and rpoB genes suggested that all of the strains should be classified as novel species of the genus Bartonella. In phylogenetic trees based on the concatenated sequences of five loci, including the 16S rRNA, ftsZ, gltA and rpoB genes and the ITS region, and on the concatenated deduced amino acid sequences of three housekeeping genes (ftsZ, gltA and rpoB), all strains formed distinct clades and had unique mammalian hosts that could be discriminated from other known species of the genus Bartonella. These data strongly support the hypothesis that strains OY2-1(T), BR11-1(T), FN15-2(T) and KS2-1(T) should be classified as representing novel species of the genus Bartonella. The names Bartonella jaculi sp. nov., Bartonella callosciuri sp. nov., Bartonella pachyuromydis sp. nov. and Bartonella acomydis sp. nov. are proposed for these novel species. Type strains of Bartonella jaculi sp. nov., Bartonella callosciuri sp. nov., Bartonella pachyuromydis sp. nov. and Bartonella acomydis sp. nov. are OY2-1(T) ( = JCM 17712(T) = KCTC 23655(T)), BR11-1(T) ( = JCM 17709(T) = KCTC 23909(T)), FN15-2(T) ( = JCM 17714(T) = KCTC 23657(T)) and KS2-1(T) ( = JCM 17706(T) = KCTC 23907(T)), respectively.

  12. Variation in the helminth community structure of Thrichomys pachyurus (Rodentia: Echimyidae) in two sub-regions of the Brazilian Pantanal: the effects of land use and seasonality.

    Science.gov (United States)

    Simões, R; Gentile, R; Rademaker, V; D'Andrea, P; Herrera, H; Freitas, T; Lanfredi, R; Maldonado, A

    2010-09-01

    The Pantanal is a large ecosystem located in South America. This preserved area is seasonally flooded due to abundant rainfall during the summer and the subsequent overflow of the Paraguai River. In this paper, we examine the helminth community structure in the wild rodent Thrichomys pachyurus during the wet and dry seasons in two locations of the preserved and cattle ranching areas in the Southern Pantanal. We identified 12 species of helminth, and, although we did not find any differences in species richness between locations within the Pantanal, we found that richness was higher during the wet season. Helminth species were largely aggregated in both farm locations and during seasons. The most common helminth species were more abundant during the dry season than during the wet season, which may have been due to the increased habitat availability and rodent population increase. The intensity of the infection also followed the same pattern for most helminths. The trichostrongylids (Heligmostrongylus crucifer, H. almeidai and Pudica cercomysi) were dominant at both farm locations. The land use of each area was not correlated with helminth diversity. However, species composition of the helminth community of T. pachyurus differed between locations and may be correlated with environmental differences between the habitats. The seasonality of the Pantanal was highly correlated with helminth parasitism in T. pachyurus.

  13. Doğu Karadeniz bölgesinde yayılış gösteren Apodemus Kaup, 1829 (Mammalia: Rodentia) cinsinin morfolojik analizi

    OpenAIRE

    2007-01-01

    Bu çalışmada Doğu Karadeniz bölgesinden örneklenen  Apodemus cinsine ait 126 örneğin  kafatası ve postları değerlendirildi. Diş, kafası ve post örneklerinin yapılan morfolojik analizleri sonucunda bu cinse ait dört tür; Apodemus uralensis, Apodemus flavicollis, Apodemus iconicus ve Apodemus mystacinus  belirlendi. Bu türlerden A. flavicollis ve A. iconicus morfolojik açıdan büyük benzerlik gösterirken, A. uralensis’ inde bu iki türe olan yakınlığı yapılan m...

  14. Four new coccidia (Apicomplexa: Eimeriidae) from the Plateau zokor, Myospalax baileyi Thomas (Rodentia: Myospalacinae), a subterranean rodent from Haibei area, Qinghai Province, China.

    Science.gov (United States)

    Cao, Yi-Fan; Nie, Xu-Heng; Zhang, Tong-Zuo; Du, Shou-Yang; Duszynski, Donald W; Bian, Jiang-Hui

    2014-02-01

    Thirty-eight faecal samples from the Plateau zokor, Myospalax baileyi Thomas, collected in the Haibei Area, Qinghai Province, China, were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Seventeen of 38 faecal samples (44.7%) were found to contain coccidian oöcysts representing four new species of Eimeria Schneider, 1875, and four of 17 (23.5%) infected zokors were concurrently infected with two or three of these eimerian species. The sporulated oöcysts of Eimeria myospalacensis n. sp. are ovoidal, 9.5-17.0 × 8.0-13.0 (mean 13.0 × 10.4) μm; a polar granule is present, oöcyst residuum is absent; sporocysts are ovoidal, 4.5-7.5 × 3.0-5.0 (mean 6.3 × 4.2) μm and have both a Stieda body and residuum. Oöcysts of Eimeria fani n. sp. are ellipsoidal to cylindroidal, 12.5-16.0 × 8.0-11.0 (mean 14.6 × 9.9) μm; a polar granule is present, but micropyle and residuum are lacking; sporocysts are ovoidal, 4.5-7.5 × 3.0-5.3 (mean 6.7 × 4.4) μm; a residuum and a Steida body are present. Oöcysts of Eimeria baileyii n. sp. are ellipsoidal, 15.0-23.0 × 12.0-18.0 (mean 18.2 × 13.7) μm; a polar granule is present but oöcyst residuum is absent; sporocysts are ovoidal, 8.0-11.0 × 5.0-7.0 (mean 9.5 × 5.9) μm and have both a Stieda body and residuum. Oöcysts of Eimeria menyuanensis n. sp. are ovoidal, 12.5-21.0 × 11.0-18.0 (mean 17.1 × 14.6) μm, with a distinct micropyle c.2.5 μm wide; a polar granule is present but a residuum is absent; sporocysts are ovoidal, 8.0-12.0 × 5.0-7.0 (mean 10.2 × 6.4) μm, and have both a Stieda body and residuum.

  15. The role of chromosomal rearrangements and geographical barriers in the divergence of lineages in a South American subterranean rodent (Rodentia: Ctenomyidae: Ctenomys minutus).

    Science.gov (United States)

    Lopes, C M; Ximenes, S S F; Gava, A; de Freitas, T R O

    2013-10-01

    Identifying factors and the extent of their roles in the differentiation of populations is of great importance for understanding the evolutionary process in which a species is involved. Ctenomys minutus is a highly karyotype-polymorphic subterranean rodent, with diploid numbers ranging from 42 to 50 and autosomal arm numbers (ANs) ranging from 68 to 80, comprising a total of 45 karyotypes described so far. This species inhabits the southern Brazilian coastal plain, which has a complex geological history, with several potential geographical barriers acting on different time scales. We assessed the geographical genetic structure of C. minutus, examining 340 individuals over the entire distributional range and using information from chromosomal rearrangements, mitochondrial DNA (mtDNA) sequences and 14 microsatellite loci. The mtDNA results revealed seven main haplogroups, with the most recent common ancestors dating from the Pleistocene, whereas clustering methods defined 12 populations. Some boundaries of mtDNA haplogroups and population clusters can be associated with potential geographical barriers to gene flow. The isolation-by-distance pattern also has an important role in fine-scale genetic differentiation, which is strengthened by the narrowness of the coastal plain and by common features of subterranean rodents (that is, small fragmented populations and low dispersal rates), which limit gene flow among populations. A step-by-step mechanism of chromosomal evolution can be suggested for this species, mainly associated with the metapopulation structure, genetic drift and the geographical features of the southern Brazilian coastal plain. However, chromosomal variations have no or very little role in the diversification of C. minutus populations.

  16. Hepatic parasitosis in two wood mice, Apodemus sylvaticus (Rodentia: Muridae), due to Aonchotheca annulosa (Nematoda: Trichuridae), and Eucoleus bacillatus (Nematoda: Trichuridae). Erratic parasitism or post mortem migration?

    Science.gov (United States)

    Debenedetti, Ángela L; Sáez-Durán, Sandra; Sainz-Elipe, Sandra; Galán-Puchades, Maria Teresa; Fuentes, Màrius V

    2014-10-01

    Aonchotheca annulosa and Eucoleus bacillatus are two capillariin nematodes parasitizing the intestinal and stomach mucosa, respectively, of various rodent species, and two, among others, component species of the helminth fauna of the wood mouse, Apodemus sylvaticus. A capillariin each was found in the liver parenchyma of two wood mice in a post-fire regeneration enclave in Serra Calderona Natural Park (Valencian Community, Spain). Due to their location, the preliminary identification of the helminths corresponded to Calodium hepaticum, a hepatic capillariin with rodents as its main host. So far, this species had never been found in Serra Calderona. To verify the preliminary identification, a comparative morphometric study between the specimens from Serra Calderona and a preserved individual of C. hepaticum from another enclave was carried out. Morphometric analysis revealed that the adult helminth as well as the eggs found in the liver of the first mouse belonged to A. annulosa, whereas the second one was identified as a male E. bacillatus. Moreover, the liver from both hosts showed a visible pathology, being the consequence of aberrant migration of the parasites. This is the first evidence that A. annulosa and E. bacillatus may migrate erratically and thus produce ectopic foci in other organs.

  17. Two New Species of Demodex (Acari: Demodecidae) with a Redescription of Demodex musculi and Data on Parasitism in Mus musculus (Rodentia: Muridae).

    Science.gov (United States)

    Izdebska, Joanna N; Rolbiecki, Leszek

    2015-07-01

    This article describes two new skin mite species found on the house mouse Mus musculus L., 1758. Demodex marculus sp. nov. is a very small demodecid mite (adult stages, on average, 99 µm in length) found in mouse skin in the abdomen, back, limbs, and anal area. It is characterized by relatively large bossing hammer-shaped supracoxal spines, embedded in the trapezoidal gnathosoma. Demodex fusiformis sp. nov., in turn, is a little larger (adult stages on average 111 µm in length), with a small oval gnathosoma equipped with fine, knob-like supracoxal spines. It was found in the skin of abdomen, back, and limbs. Moreover, Demodex musculi (Oudemans, 1897) was redescribed, which is small demodecid mite (adult stages on average 142 µm in length) and characterized by relatively large morphological variation and considerable sexual dimorphism. The characteristic feature of this species is the strongly elongated and rectangular gnathosoma equipped with very large wedge-shaped supracoxal spines. D. musculi was found in the skin of various, haired regions of the mice body (head, neck, abdomen, back, limbs, genital-anal region, and tail). Moreover, one more demodecid mite was found in the skin of the examined mice, it was Demodex flagellurus Bukva, 1985, which was found only in the genital area. Overall infection of Mus musculus L. by all species of Demodex was with the prevalence of 100%, mean intensity of 24.0, and range of intensity of 1-109. Despite high infection levels, no symptoms of parasitosis were observed in the hosts.

  18. Demodectic mites of the brown rat Rattus norvegicus (Berkenhout, 1769) (Rodentia, Muridae) with a new finding of Demodex ratticola Bukva, 1995 (Acari, Demodecidae).

    Science.gov (United States)

    Izdebska, Joanna N; Rolbiecki, Leszek

    2012-01-01

    Demodex ratticola was recorded in the brown rat Rattus norvegicus from northern Poland. It is a skin mite specific to this host, previously recorded only in the Czech Republic. D. ratticola was found at a prevalence 65.0% and mean intensity 12.7 in skin samples taken from the regions of lips, nose and chin. Furthermore, three other species from the family of Demodecidae were recorded, including Demodex nanus found in skin samples from different parts of the body and characterised by the highest parameters of infestation (100.0%, 25.2), D. ratti (50.0%, 3.3) found in the head skin and D. norvegicus (30.0%, 3.5) found in the genital and anal regions. The identified demodectic mites did not cause any pathological symptoms in rats.

  19. A new species of Demodex (Acari: Demodecidae) with data on topical specificity and topography of demodectic mites in the striped field mouse Apodemus agrarius (Rodentia: Muridae).

    Science.gov (United States)

    Izdebska, Joanna N; Rolbiecki, Leszek

    2013-11-01

    This article describes morphological characteristics and the occurrence of Demodex gracilentus sp. nov., which was found in the striped field mouse Apodemus agrarius (Pallas, 1771) in the skin of vibrissae area. D. gracilentus occurred in 36.7% of the rodents examined. D. gracilentus is a relatively large representative of the genus (adult stages on average 292 microm in length), a slender, elongated body; characteristic feature of these mites are conical supracoxal spines on dorsal side of gnathosoma, palps with asymmetric, forked triple spines on palptarsus, and the presence of rhomboidal opisthosomal organ. So far, the occurrence of three specific representatives of the family Demodecidae has been demonstrated in A. agrarius: Demodex apodemi (Hirst, 1918) (= Demodex arvicolae apodemi Hirst, 1918), Demodex agrarii Bukva, 1994, and Demodex huttereri Mertens, Lukoschus et Nutting, 1983. The first one is related to common hair follicles, especially in the skin of the head, while the next one inhabits the external auditory meatus, and the last one occurs in the meibomian glands of the eyelids.

  20. A new species of the genus Demodex Owen, 1843 (Acari: Demodecidae) from the ear canals of the house mouse Mus musculus L. (Rodentia: Muridae).

    Science.gov (United States)

    Izdebska, Joanna N; Rolbiecki, Leszek

    2015-06-01

    A new species Demodex conicus n. sp. is described based on adult and juvenile stages from the ear canals of the house mouse Mus musculus L. in Poland. The new species is most similar to D. auricularis Izdebska, Rolbiecki & Fryderyk, 2014 from the ear canals of the wood mouse Apodemus sylvaticus (L.), but differs in the following features: the gnathosoma is triangular, the supracoxal spines (setae elc.p) are conical, the spines on the terminal segment of palp are four, the striation on opisthosoma is fine but dense, the vulva is located at a distance of c.17 µm from posterior level of legs IV, and the male genital opening is located at the level of legs I. The differences also relate to body size and proportions, female D. conicus n. sp. being, on average slightly larger, and male significantly larger than D. auricularis. Males of the new species also have longer and more massive opisthosoma than males of D. auricularis. Demodex conicus n. sp. was found in 17.5% of the mice studied from different locations in Poland.

  1. Extinction of endemic vertebrates on islands : The case of the giant rat Canariomys bravoi (Mammalia, Rodentia) on Tenerife (Canary Islands, Spain)

    NARCIS (Netherlands)

    Bocherens, Herve; Michaux, Jacques; Talavera, Francisco Garcia; Van der Plicht, Johannes

    2006-01-01

    Fossil bone collagen (14)C dating and delta(13)C and delta(15)N isotopic measurements of the rodent Canariomys bravoi from Tenerife (Canary Islands.. Spain) were used to test two different hypotheses about the causes of extinctions of endemic vertebrates on islands. climate versus humans. For the Te

  2. A influência do tempo de permanência em cativeiro sobre o comportamento: Um estudo de caso com Trinomys yonenagae (Rodentia: Echimyidae)

    OpenAIRE

    Alves, Ilai Moradillo Mello

    2013-01-01

    A utilização de animais silvestres em experimentos é freqüentemente precedida pela aclimatação ao cativeiro, de modo a permitir que eles se habituem às condições nas quais serão mantidas e nas quais serão realizados os experimentos. No entanto, nem sempre essa habituação pode ser benéfica no que diz respeito à qualidade dos dados coletados de modo que o comportamento, a fisiologia e o bem-estar dos animais podem ser fortemente afetados por essa aclimatação. Apesar de os roedores sere...

  3. Respuesta de Sigmodon hispidus (Rodentia: Muridae) a la inoculación experimental con el virus de la estomatitis vesicular serotipo New Jersey

    OpenAIRE

    Rodriguez, Julia; Dolz, Gaby; Jimenez, Ana Eugenia; Herrero, Marco Vinicio; Salman, Mo

    2013-01-01

    Se han reportado anticuerpos contra el Virus de Estomatitis Vesicular, serotipo New Jersey (VEV-NJ), en Sigmodon hispidus (rata algodonera) libres en Costa Rica. Con el fin de evaluar su respuesta ante el virus y su potencial rol como reservorio, treinta ratas algodoneras adultas, criadas en laboratorio, fueron inoculadas experimentalmente con 107 TCID50/ml VEV-NJ de la siguiente manera: 10 vía subcutánea (grupo A), 10 por abrasión oral (grupo B) y 10 por vía intranasal (grupo C). Se incluyer...

  4. [Annual follow-up of the gastrointestinal parasitosis of the tepezcuintle, Agouti paca (Rodentia: Agoutidae) in captivity in the Mexican tropic].

    Science.gov (United States)

    Ramírez-Herrera, O; Rodríguez-Vivas, R I; Montes-Pérez, R; Torres-Acosta, J F

    2001-01-01

    Previous reports showed that the tepezcuintle (Agouti paca) is commonly infested by gastrointestinal parasites (GIP), mainly Eucoccidiida and helminths. However, there is no available information on the frequency of those parasites and their faecal egg excretions at different moments during the year. These information would provide a valuable baseline for the establishment of control strategies against GIP in tepezcuintles under captivity. The objectives of the present study were to determine the prevalence of GIP orders and genera that infest tepezcuintles under captivity and, to describe the dynamics of faecal egg and oocyst excretion in a year. Ten tepezcuintles were sampled (faeces) twice every month for twelve months. The faecal samples were processed by the flotation and McMaster techniques. Two orders of parasites were determined: Strongylida and Eucoccidiida. Two genera of nematodes were also determined: Strongyloides and Trichuris. The prevalence of Strongylida eggs, Eucoccidiida oocysts and Trichuris sp. eggs reached 10-20% of animals in certain months. The most important genus was Strongyloides, found in 60 to 100% of the animals year round. The average excretion of eggs in the group was 45 to 372 eggs per gram. Tepezcuintles kept under captivity in Yucatan are parasited with Strongyloides sp throughout the year, but only occasionally had oocysts of Eucoccidiida and eggs of Strongylida and Trichuris sp.

  5. Life in Burrows Channelled the Morphological Evolution of the Skull in Rodents: the Case of African Mole-Rats (Bathyergidae, Rodentia)

    OpenAIRE

    2015-01-01

    International audience; African mole-rats are fossorial rodents that consist of five chisel-tooth digging genera (Heterocephalus, Heliophobius, Georychus, Fukomys, and Cryptomys) and one scratch digger (Bathyergus). They are characterized by striking physiological, morphological, and behavioral adaptations intimately related to their subterranean life. The influence of their mode of life in shaping the cranial morphology has yet to be evaluated in comparison to other Ctenohystrica, especially...

  6. Lineage-specific responses of tooth shape in murine rodents (murinae, rodentia) to late Miocene dietary change in the Siwaliks of Pakistan.

    Science.gov (United States)

    Kimura, Yuri; Jacobs, Louis L; Flynn, Lawrence J

    2013-01-01

    Past ecological responses of mammals to climate change are recognized in the fossil record by adaptive significance of morphological variations. To understand the role of dietary behavior on functional adaptations of dental morphology in rodent evolution, we examine evolutionary change of tooth shape in late Miocene Siwalik murine rodents, which experienced a dietary shift toward C4 diets during late Miocene ecological change indicated by carbon isotopic evidence. Geometric morphometric analysis in the outline of upper first molars captures dichotomous lineages of Siwalik murines, in agreement with phylogenetic hypotheses of previous studies (two distinct clades: the Karnimata and Progonomys clades), and indicates lineage-specific functional responses to mechanical properties of their diets. Tooth shapes of the two clades are similar at their sympatric origin but deviate from each other with decreasing overlap through time. Shape change in the Karnimata clade is associated with greater efficiency of propalinal chewing for tough diets than in the Progonomys clade. Larger body mass in Karnimata may be related to exploitation of lower-quality food items, such as grasses, than in smaller-bodied Progonomys. The functional and ecophysiological aspects of Karnimata exploiting C4 grasses are concordant with their isotopic dietary preference relative to Progonomys. Lineage-specific selection was differentially greater in Karnimata, and a faster rate of shape change toward derived Karnimata facilitated inclusion of C4 grasses in the diet. Sympatric speciation in these clades is most plausibly explained by interspecific competition on resource utilization between the two, based on comparisons of our results with the carbon isotope data. Interspecific competition with Karnimata may have suppressed morphological innovation of the Progonomys clade. Pairwise analyses of morphological and carbon isotope data can uncover ecological causes of sympatric speciation and define functional adaptations of teeth to resources.

  7. Parasitism of two zoonotic reservoirs Dasyprocta leporina and D. fuliginosa (Rodentia from Amazonas, with Trichostrongylina nematodes (Heligmonellidae: description of a new genus and a new species

    Directory of Open Access Journals (Sweden)

    Alessandra Queiroga Gonçalves

    2007-09-01

    Full Text Available A new genus and a new species of Heligmonellidae nematodes are described parasiting the stomach of three agoutis (two Dasyprocta fuliginosa and one D. leporina captured in the middle and high Negro river microregion, state of Amazonas, Brazil. The new genus, as well as its type-species, are closely related to the trichostrongylids included in Fuellebornema, particularly on what concerns the pattern of the caudal bursa, but differing from them by the characteristics of the synlophe, that presents a poorly developed carene, when compared to the referred number of body ridges in Freitastrongylus n. gen. and consequently in F. angelae n. sp.,in which the ridges are well developed and the carene at mid-body has a similar size when compared to the ridge situated in front of the right field (ridge no. 5. Caudal bursa is of the type 1-4, with rays 9 shorter than rays 10, with a very long genital cone.

  8. [A modular approach to studying of fluctuating asymmetry of complex morphological structures in rodents with the mandible of the bank vole (Clethrionomys glareolus, Arvicolinae, Rodentia) as an example].

    Science.gov (United States)

    Ialkovskaia, L É; Borodin, A V; Fominykh, M A

    2014-01-01

    The expediency of a modular approach to estimating fluctuating asymmetry (FA) of complex morphological structures was shown using the mandible of the bank vole (Clethrionomys glareolus Schreber, 1780) as an example. FA of the shape of two mandibular regions (modules) defined developmentally and functionally, was assessed by means of geometric morphometrics. The differences between mandibular regions in the FA levels were found for both individual landmarks and integral indices of asymmetry. Regardless of age, gender or sampling year, FA estimates obtained for posterior region including part of the ramus and processes were higher than those for anterior region including the diastemal area. The results suggest that modularity of complex morphological structures should be taken into account when analyzing FA.

  9. Biochemical Changes of the Organism of Apodemus flavicollis (Rodentia: Muridae Under Conditions of Environmental Anthropogenic Pollution by Heavy Metals in Northern Areas of Ukraine

    Directory of Open Access Journals (Sweden)

    Svitlana V. Zadyra

    2014-04-01

    Full Text Available The present research dedicates the integral assessment of biochemistry indexes of nature populations of rodents under conditions of environment pollution by heavy metals. The raised content in soils of mobile forms Pb, Cd, Cr, Ni and Co was revealed оn distance of 500 m to the South-West from Tripillya Thermal Power Plant (Kyiv region, Ukraine. That’s considerably (3–5 times exceeds levels for territory of Kaniv Nature Reserve (Cherkassy region, Ukraine. Territory of National Nature Park “Holosiivsky” (Kyiv, Ukraine characterized by rather increased content of active form of researched heavy metals especially Pb. Increase of the concentration of diene conjugates (3–7 times and malonic dialdehyde (2–4 times in yellow-necked mouse liver (Apodemus flavicollis of under pollution by heavy metals has been discovered. Insignificant increasing of content of Schiff basis in liver cells of rodents in region of impact of Tripillya TPP (in 2 times in spring and in summer, in autumn – in 2.5 times was detected. Seasonal dynamics of the maintenance of lipid peroxidation has been revealed. The registered changes of biochemical indicators testify about presence ecological-biochemical stress in an organism of the yellow-necked mouse in the district of influence of Tripillya TPP.

  10. Causes and consequences of change rates in the habitat of the threatened tropical porcupine, Sphiggurus mexicanus (Rodentia: Erethizontidae) in Oaxaca, Mexico: implications for its conservation.

    Science.gov (United States)

    Lorenzo, Consuelo; Sántiz, Eugenia C; Navarrete, Darío A; Bolaños, Jorge

    2014-12-01

    Land use changes by human activities have been the main causes of habitats and wildlife population degradation. In the Tehuantepec Isthmus in Oaxaca, the tropical habitat of the porcupine Sphiggurus mexicanus has been subject to vegetation and land use changes, causing its reduction and fragmentation. In this study, we estimated vegetation cover and land use (δn) change rates and assessed habitat availability and potential cor- ridors for possible porcupine movements to avoid its isolation. In the study area, the type of vegetation with the most change rate value was the savanna (δn = -2.9), transformed into induced grasslands. Additionally, we have observed the porcupine (since 2011) in semi-deciduous (δn = -0.87) and tropical dry (δn = -0.89) forests that have been transformed in temporal agriculture and mesquite and induced grasslands. The vegetation inhabited by the porcupine resulted in recording a total of 64 plant species (44 trees, nine vines, seven herbs, four shrubs), of which the vine Bunchosia lanceolata showed the highest importance value (41.85) followed by the trees Guazuma ulmifolia (22.71), Dalbergia glabra (18.05), and Enterolobium cyclocarpum (17.02). The habitat evaluation and potential corridor analysis showed that only 1 501.93ha could be considered as suitable habitats with optimum structural conditions (coverage, surface, and distances to transformed areas) to maintain viable populations of S. mexicanus, and 293.6 ha as corridors. An increasing destruction of the porcupines' habitat has been observed in the study area due to excessive logging, and actions for this species and its habitat conserva- tion and management have to be taken urgently.

  11. Free and total testosterone levels in field males of Octodon degus (Rodentia, Octodontidae: accuracy of the hormonal regulation of behavior Niveles de testosterona libre y totales en machos silvestres de Octodon degus (Rodentia, Octodontidae: exactitud de la regulación hormonal del comportamiento

    Directory of Open Access Journals (Sweden)

    MAURICIO SOTO- GAMBOA

    2005-06-01

    Full Text Available Animals exhibit continuous seasonal changes in physiological, morphological and behavioral traits associated to their natural annual cycles. One of the most important changes in the organism occurs at the initiation of breeding season. In males these changes include activation of spermatogenesis, enhance of sexual secondary characters and an increase of aggressiveness. All of theses changes are basically regulated by testosterone, but the physiological basis of this testosterone regulation and the effective hormone proportion that acts in target tissues are unknown. In this work I evaluated the relationship between total testosterone, free testosterone associated to aggressive behavior in wild males of Octodon degus. I compared hormonal levels and aggressive behavior during pre, middle and post breeding periods. Results showed that behavioral aggressiveness was correlated with both total and free testosterone in June, during the beginning of breeding season, but not at other times. Results also indicated a lack of relationship between free and total testosterone in most of breeding period. I discuss the importance of this behavior-hormonal regulation (determined by free testosterone and the physiological importance of this mechanism to the organismLos animales presentan variaciones estacionales continuas que incluyen cambios fisiológicos, morfológicos y conductuales, asociados al ciclo anual. Estos cambios generalmente están activados por factores endógenos o exógenos, pero son regulados por el sistema endocrino de organismo. Uno de los cambios más importantes ocurre en el inicio del periodo reproductivo. Durante este periodo los machos presentan cambios asociados a la producción de esperatozoides, exacerbación de caracteres sexuales secundarios y un aumento de la agresividad. Todos estos cambios son regulados en parte por los niveles de testosterona, sin embargo, los mecanismos fisiológicos de esta regulación son desconocidos. En este trabajo evalué la relación que existe entre los niveles de testosterona libre y totales, y examiné su posible asociación con los niveles de agresividad en machos de una población natural de Octodon degus. Mis resultados indicaron que la agresividad se correlaciona directamente con los niveles de testosterona libre y totales solo durante el mes de junio, al inicio del periodo reproductivo, pero no durante el resto del ciclo reproductivo de esta especie. Esto indicaría que la agresividad solo se correlaciona con los niveles de testosterona libre ya que en el medio y el final del periodo reproductivo los niveles de testosterona se mantienen altos sin que se manifiesten dichas conductas. Finalmente, discuto la importancia de la regulación fina de la conducta determinada por la testosterona libre y la importancia fisiológica de este mecanismo de regulación dentro del organismo

  12. Endoparasitos em cobaias (Cavia porcellus (Mammalia, Rodentia, Caviidae provenientes de biotérios de criação e experimentação do município do Rio de Janeiro, Brasil Endoparasites in guinea pigs (Cavia porcellus (Mammalia, Rodentia, Caviidae from breeding and experimentation animal housing of the municipality of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Luciana Casartelli Alves

    2007-10-01

    Full Text Available Foi realizado um levantamento sobre a prevalência e intensidade de infecção de endoparasitos em cobaias convencionais de linhagem Short Hair provenientes de biotérios de criação (A e experimentação (B do município do Rio de Janeiro, Brasil, avaliando-se a eficácia das medidas de prevenção entre eles. Para a realização do estudo, utilizou-se exame direto de mucosa e do conteúdo intestinal, a técnica de tricromo de WHEATLEY e exames coproparasitológicos pelas técnicas de Ritchie e Kinyoun. Os parasitos encontrados através da técnica de exame direto da mucosa e do conteúdo intestinal e de tricromo de WHEATLEY com as respectivas prevalências foram: Balantidium sp. (78%, Cyathodinium sp. (68%, Eimeria caviae (38%, Paraspidodera uncinata (34% e Giardia muris (24%. Nos exames de fezes realizados pelas técnicas de Ritchie e Kinyoun, foram encontrados os seguintes parasitos com as respectivas prevalências no biotério A: E. caviae (74%, Balantidium sp. (68%, Cyathodinium sp. (68% e Cryptosporidium sp. (5%. No biotério B, observou-se: E. caviae (58%, Balantidium sp. (42%, Cyathodinium sp. (25% e G. muris (8%. A alta prevalência de endoparasitos nos biotérios sugere a necessidade de se rever a eficácia das barreiras sanitárias adotadas.This paper discusses the prevalence and intensity of infection of endoparasites in conventionally maintained Short Hair guinea pigs colonies from a breeding (A and an experimental (B facilities in Rio de Janeiro, Brazil. It also evaluates the efficacy of the methods of prevention adopted by both facilities. The search of parasites was performed by direct examination of intestinal mucosa and its contents, WHEATLEY's trichrome method and coproparasitological examinations by Ritchie's and Kinyoun's techniques. The prevalences of endoparasites found throught direct examination of intestinal mucosa and its contents were: Balantidium sp. (78%, Cyathodinium sp. (68%, Eimeria caviae (38%, Paraspidodera uncinata (34% and Giardia muris (24%. The prevalences of endoparasites found throught Ritchie's and Kinyoun's techniques in facility A were: E. caviae (74%, Balantidium sp. (68%, Cyathodinium sp. (68% and Cryptosporidium sp. (5%. In facility B: E. caviae (58%, Balantidium sp. (42%, Cyathodinium sp. (25% and G. muris (8% were found. The high prevalences in both facilities suggest that the efficacy of the sanitary barriers adopted in the prevention of parasitic infections should be revised.

  13. Infección inducida en el roedor selvático Dasyprocta leporina (Rodentia: Dasyproctidae, con huevos larvados de Lagochilascaris minor (Nematoda: Ascarididae Induced infection in the wild rodent Dasyprocta leporina (Rodentia: Dasyproctidae with larval eggs of Lagochilascaris minor (Nematoda: Ascarididae

    Directory of Open Access Journals (Sweden)

    S. Gregorio

    1990-12-01

    Full Text Available Ejemplares de Dasyprocta leporina Linnaeus, 1758 fueron criados alejados de su ambiente natural. A los 3 ó 4 meses de edad, se los inoculó por vía oral con huevos de Lagochilascaris minor Leiper, 1909 obtenidos de una paciente nativa. Los huevos se los incubó por más de 80 dias, para que de ellos fuese posible obtener por compresión mecánica, larvas que se mantuviesen vivas en medio acuoso por 48 horas o más. Sacrificados los animales a los 14 ó 46 dias posteriores a la infección, se hallaron en los músculos esqueléticos larvas ovilladas dentro de nódulos inflamatorios, los cuales no presentaban reacción a cuerpo extraño, abscedación o calcificación. El desarollo de los nódulos no parecía afectar la normalidad de los hospedadores. Las larvas obtenidas eran similares a las descritas por SPRENT como de tercer estadio para estos helmintos. Ratones blancos infectados con material similar, no presentaron nódulos en sus músculos ni se pudo recuperar de sus tejidos larva alguna. Por los hallazgos obtenidos con la infección de estos animales, se postula que el helminto no posee ciclo pulmonar y que su desarrollo requiere de un hospedador intermediario.Specimens of Dasyprocta leporina (Linnaeus, 1758 were raised out their natural environment. At three to four months of age they were orally inoculated with Lagochilascaris minor (Leiper, 1909 eggs obtained from a native patient. The eggs were incubated for more than 80 days so that it was possible to obtain, by mechanical compression, larvae that could be maintained alive in liquid medium for 48 hours or more. The animals were sacrificed 14-46 days after infection and tangled larva in inflammatory nodules were found in skeletal muscle without foreign body reaction, abscess formation or calcification. The development of the nodules did not seem to affect the hosts. The larvae obtained were similar to those described by SPRENT as the third stage of these helminths. When white mice were inoculated with similar material it was not possible to recuperate larva from their tissues nor were nodules found. Based on these results it is postulated that the helminth does not present a pulmonary cycle and that its development requires an intermediary host.

  14. Ectoparásitos Asociados a Machos y Hembras de Oxymycterus rufus (Rodentia: Muridae: Estudio comparativo en la Selva Marginal del río de La Plata, Argentina Ectoparasites Associated with Males and Females of Oxymycterus rufus (Rodentia: Muridae: Comparative Study in La Plata River Marshland, Argentina

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    Marcela Lareschi

    2004-12-01

    Full Text Available El objetivo del presente estudio es comparar parámetros e índices de infestación de los ectoparásitos asociados a cada sexo de Oxymycterus rufus (Fischer. El índice de densidad relativa de los machos fue 4,4% y el de las hembras 5,0%. Se recolectaron 873 ectoparásitos de 38 machos y 1015 de 43 hembras. La riqueza y la diversidad específica de los ectoparásitos fueron 12,0 y 1,2 en los machos, 11,0 y 0,7 en las hembras. La similitud entre machos y hembras de acuerdo a sus ectoparásitos fue del 87%. Los resultados obtenidos muestran que el sexo del huésped influenciaría la prevalencia y abundancia media de aquellas especies ectoparásitas que en estudios previos mostraron preferencia por O. rufus, tales como Androlaelaps fahrenholzi (Berlese (abundancia media = 3,5 y prevalencia = 65,8% en los machos; abundancia media = 1,6 y prevalencia = 50,0% en las hembras, Eutrombicula alfreddugesi (Oudemans (abundancia media = 10,9 y prevalencia = 29,0% en los machos; abundancia media = 18,7 y prevalencia = 32,6% en los machos y Ornithonyssus bacoti (Hirst (abundancia media = 7,8 y prevalencia = 63,0% en los machos; abundancia media = 2,7 y prevalencia = 52,6% en las hembras. Esta información es importante desde un punto de vista epidemiológico.Infestation parameters and indexes of ectoparasites associated with each sex of Oxymycterus rufus (Fischer are compared. Males relative density index = 4.4%, females RDI = 5.0%. A total of 873 ectoparasites were collected on 38 males, and 1015 on 43 females; specific richness = 12.0, specific diversity = 1.2 on males, and S = 11.0 H = 0.7 on females. The similarity between both sexes according to their ectoparasites was of 87.0%. The results obtained show that host sex may influence on the prevalence and mean abundance of those ectoparasites which in previous studies have showed preference for O. rufus, such as Androlaelaps fahrenholzi (Berlese (mean abundance = 3.5 and prevalence = 65.8% in males; mean abundance = 1.6 and prevalence = 50.0% in females, Eutrombicula alfreddugesi (Oudemans (mean abundance = 10.9 and prevalence = 29.0% in males; mean abundance = 18.7 and prevalence = 32.6% in females and Ornithonyssus bacoti (Hirst (mean abundance = 7.8 and prevalence = 63.0% in males; mean abundance = 2.7 and prevalence = 52.6% in females. This information is important since an epidemiological viewpoint.

  15. Intraspecific differences in metabolic rate of Chroeomys olivaceus (Rodentia: Muridae: the effect of thermal acclimation in arid and mesic habitats Diferencias intraespecíficas en la tasa metabólica de Chroeomys olivaceus (Rodentia: Muridae: efecto de la aclimatación térmica en hábitat áridos y mésicos

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    F. Fernando Novoa

    2005-06-01

    Full Text Available Studies of metabolic capacities in rodents have been largely studied at an inter-specific levels, but physiological capacities of populations belonging to the same species have received lesser attention. Here we studied the maximum and basal metabolic rates of two populations of the rodent Chroeomys olivaceus dwelling in habitats with contrasting temperature and rainfall regimes, and to test if differences in metabolic capacities are due to local adaptation or acclimatization effect. After four weeks of acclimation to 25 ºC and 10 ºC, the BMR and MMR were determined in individuals from the northern population of Caleta Loa, and the southern population of La Picada. Individuals from ‘La Picada’ population were heavier than those from Caleta Loa. MMR and BMR exhibited higher values in cold acclimated animals compared with warm-acclimated animals. Besides, BMR, but not MMR, was lower in Caleta Loa individuals, in spite of the acclimation treatment. Hence, the differences in the metabolic capacities and the response to acclimation of C. olivaceus populations appear to be an evolutionary response to the environmental cuesLas capacidades metabólicas en roedores han sido ampliamente estudiadas en un nivel ínterespecífico, pero los atributos fisiológicos de las poblaciones que pertenecen a una misma especie, han recibido menos atención. Aquí estudiamos las tasas metabólicas máximas y basales de dos poblaciones del roedor Chroeomys olivaceus que viven en habitats con temperaturas y regímenes de precipitaciones contrastantes y se analiza si las diferencias en las capacidades metabólicas se deben a diferenciación local o a efectos de aclimatación. Después de cuatro semanas de aclimatación a 25 ºC y 10 ºC, el BMR y MMR fueron determinados en individuos de la población norteña de Caleta Loa y en la población sureña de "La Picada". Los individuos de la población "La Picada" presentaron mayor masa corporal que los de Caleta Loa. Los valores de MMR y BMR fueron más altos en animales aclimatados al frío, comparados con los aclimatados a temperaturas más cálidas. Asimismo, sólo BMR y no MMR, fue más bajo en los individuos de Caleta Loa, a pesar del tratamiento de aclimatación. Por lo tanto, las diferencias en las capacidades metabólicas y en la respuesta a la aclimatación de las poblaciones de C. olivaceus, parecen ser una respuesta evolutiva a las claves ambientales

  16. Identificación de los mecanismos subyacentes a la invasión de Castor canadensis (Rodentia en el archipiélago de Tierra del Fuego, Chile Identifying the mechanisms underlying the invasion of Castor canadensis (Rodentia into Tierra del Fuego archipelago, Chile

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    PETRA K WALLEM

    2007-09-01

    Full Text Available Castor canadensis es considerado un ingeniero ecosistémico arquetípico, ya que altera el estado de factores bióticos y abióticos, mediante interacciones no tróficas, modificando sustancialmente los ecosistemas que habita. Esta especie fue introducida en la Isla Grande de Tierra del Fuego en 1946 por el gobierno argentino, con el fin de estimular la industria peletera. Actualmente se encuentra presente en las principales islas del archipiélago, incluyendo Tierra del Fuego, Navarino, Dawson y Hoste y ocupando habitat tan contrastantes como los bosques subpolares magallánicos, el matorral y la estepa patagónica. Su éxito en estos habitat sugiere que su expansión solo se verá limitada por la disponibilidad de recursos hídricos. De acuerdo a lo observado en Tierra del Fuego, en ausencia de un programa de control poblacional, los castores amenazan con establecerse en todos los bosques templados nativos del continente (entre los 35 y 55° S y ocupar los habitat de matorral y pastizal circundantes a los mismos. El presente artículo propone tres hipótesis referentes a los mecanismos subyacentes al éxito de esta invasión: el escape de enemigos naturales, la oportunidad de recursos, y la autofacilitación mediante interacciones no tróficas. Los antecedentes disponibles develan patrones conductuales (e.g., el establecimiento de colonias en forma independiente de la cercanía de recursos maderables, un aparente crecimiento poblacional irruptivo, así como una explotación centrada en Nothofagus pumilio, especie dominante en los bosques magallánicos que sugieren la operación de los mecanismos de escape de enemigos naturales y oportunidad de recursos. También se observa una mayor densidad de colonias activas en habitat que presentan mayor extensión de modificación ambiental, sugiriendo el accionar del mecanismo de autofacilitación. Si bien la información reunida no permite poner a prueba las hipótesis propuestas, sí entrega un marco conceptual sobre el cual se pueden desarrollar futuras investigaciones referentes a esta invasiónCastor canadensis is considered an archetypical ecosystem engineer, which modifies the state of biotic and abiotic factors through non-trophic interactions. This species was introduced by the Argentinean government into Tierra del Fuego island in 1946, and subsequently colonized autonomously the neighboring islands of Navarino, Dawson and Hoste. Currently this invader occupies contrasting ecosystems such as the Magellan subpolar beech forest and Patagonian scrub and steppe. This ability to colonize contrasting habitats suggests that beaver expansion will be limited mainly by hydrological resources, threatening to colonize the complete extent of temperate beech forests on the mainland (from 35 to 55° S. The present review proposes three hypotheses regarding the underlying mechanisms to this successful invasion: natural enemy escape, resource opportunities, and self-facilitation through non-trophic interactions. Current knowledge regarding beaver colonization and foraging behavior (e.g., habitat selection independently of forest availability, irruptive population growth, and apparent selective exploitation of Nothofagus pumilio, dominant species in the Magellan forest suggests that enemy escape and resource opportunity are the main mechanisms underlying this invasion. The observation of higher densities of active colonies, where the extent of beaver habitat modification is larger, suggests that self-facilitation may be relevant to the success of this invasion. Current information does not allow testing these hypotheses, but it provides a framework to develop future investigations regarding this invasion in Tierra del Fuego

  17. [Biostratigraphy and paleoecology of the Neogene micromammalian faunas from the Calatayud-Teruel Basin (Spain) / Freudenthal, M. (editor)]: Rodents and lagomorphs from a lower Vallesian fissure filling near Molina de Aragon (Prov. Guadalajara, Spain)

    NARCIS (Netherlands)

    Anduenza, J.I.L.

    1988-01-01

    A new lower Vallesian micromammalian fauna from a locality near Molina de Aragon is described. Five species of Cricetidae, three species of Sciuridae - including a new one (Heteroxerus molinensis) -, two species of Gliridae, and one lagomorph species are described. Also, the paleoecological implicat

  18. The micromammal fauna from the upper Oligocene of Sayatón 6, Madrid Basin, Prov. of Guadalajara, Spain

    NARCIS (Netherlands)

    Daams, R.

    1989-01-01

    The extremely poor rodent fauna of Sayatón 6 is described. Only three species are present, of which two are new: Adelomyarion alberti sp. nov. (Cricetidae) and Peridyromys columbarii sp. nov. (Gliridae). The third species, Rhodanomys transiens, places the age of the fauna in the Late Oligocene.

  19. Size variation in samples of fossil and recent murid teeth

    NARCIS (Netherlands)

    Freudenthal, M.; Martín Suárez, E.

    1990-01-01

    The variability coefficient proposed by Freudenthal & Cuenca Bescós (1984) for samples of fossil cricetid teeth, is calculated for about 200 samples of fossil and recent murid teeth. The results are discussed, and compared with those obtained for the Cricetidae.

  20. The gastrointestinal helminths of Rattus niobe (Rodentia: Muridae) with descriptions of two new genera and three new species (Nematoda) from Papua New Guinea and Papua Indonesia.

    Science.gov (United States)

    Smales, L R

    2016-05-31

    Cestodes, to be identified elsewhere, the acanthocephalan Moniliformis moniliformis and 15 species of nematode including 2 new genera, a new species and 2 putative new species from the families Heligmonellidae and Oxyuridae, as well as juveniles and a putative heligmonellid that could not be fully identified, were collected from the digestive tracts of 34 Rattus niobe (Muridae: Murinae: Rattini) from Papua, Indonesia and Papua New Guinea. The ascaridid, Toxocara mackerrasae, the chabertiid Cyclodontostomum purvisi, the heterakid Heterakis sp., the spirurids Protospirura kaindiensis and P. muricola the subulurid Subulura andersoni and the trichurids Eucoleus sp. and Trichuris muris have been reported previously from endemic Rattus spp. Syphacia (Syphacia) niobe n. sp. was distinguished from its congeners by a combination of characters including a round cephalic plate, the lack of cervical and lateral alae, a longer male tail and an attenuated female tail. Nugininema titokis n. gen., n. sp. differs from all other genera in the Heligmonellidae in the characters of the synlophe, 10-17 ridges orientated subfrontally at mid body and 2 right ventral ridges hypertrophied anteriorly. Rodentanema aenigma n. gen., n. sp. differs from all other genera in the Heligmonellidae in the characters of the synlophe 6-7 ridges at mid body not symmetrical in relation to frontal axis. Species richness of the nematode assemblage was similar to that reported for Rattus leucopus in Papua New Guinea, with about 90% of possible species found as indicated by bootstrap analysis. Species composition included 6 species unique to R. niobe and 7 species reported from at least one other species of Rattus indigenous to New Guinea, as well as juvenile worms, probably ascaridids.

  1. [Morphology and biometry of eggs and larvae of Strongyloides sp. Grassi, 1879 (Rhabditoidea: Strongyloididae), a gastrointestinal parasite of Hydrochaeris hydrochaeris (Linnaeus, 1766) (Rodentia: Hydrochaeridae), in the municipality of Juiz de Fora, Minas Gerais, Brazil].

    Science.gov (United States)

    Vieira, Fabiano M; Lima, Sueli de S; Bessa, Elisabeth Cristina de A

    2006-01-01

    An important method to diagnose and study the helminthofauna of wild animals is to examine the host's feces to find eggs and larvae, seeking to identify the parasites and study their morphobiology. The objective of the present work is to provide morphological and biometric data on the eggs and larvae of Strongyloides sp., a capybara gastrointestinal parasite. Using the technique of Gordon and Whitlock, simple flotation and the modified Baermann examination, capybara fecal samples were selected based on a criterion of the highest proportion of eggs and larvae in the initial development stages, for morphometric description of eggs, L1, L2 and L3 of Strongyloides sp. From past reports of parasitism in Hydrochaeris hydrochaeris, we suspect that the eggs and larvae in this study are of Strongyloides chapini Sandground, 1925, which constitutes the first description of these stages for this species of nematode. Nevertheless, the morphology and biometry data of these stages demonstrate that they are similar to those of other species of the Strongyloides genus.

  2. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877) – Rodentia, Echimyidae – population with varying jackfruit tree (Artocarpus heterophyllus L.) abundances

    OpenAIRE

    Mello,JHF; Moulton,TP; Raíces,DSL; Bergallo,HG.

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and d...

  3. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877) - Rodentia, Echimyidae - population with varying jackfruit tree (Artocarpus heterophyllus L.) abundances.

    Science.gov (United States)

    Mello, J H F; Moulton, T P; Raíces, D S L; Bergallo, H G

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i) to calculate the carrying capacity K based on real data of the involved species and the environment; ii) propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii) determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  4. [Leishmania major Yakimoff et Schokhor, 1914 (Kinetoplastida: Trypanosomatidae) in Meriones shawi Duvernoy, 1842 (Rodentia: Gerbillidae): persistence of the infection in meriones and its infectivity for the sand fly vector (Phlebotomus) papatasi Scopoli, 1786 (Diptera: Psychodidae).

    OpenAIRE

    Derbali, M.; Chelbi, I.; Ben Hadj Ahmed, S.; Zhioua, E.

    2012-01-01

    International audience; The ability of the sand fly Phlebotomus papatasi to transmit Leishmania major, the etiologic agent of zoonotic cutaneous leishmaniasis, to Meriones shawi, the natural reservoir host of this parasite, was studied under laboratory conditions. Sand flies became infected with L. major after feeding on a lesion of needle-inoculated M. shawi. Moreover, P. papatasi, previously infected with L. major, transmitted the parasite to M. shawi by bite during a second bloodmeal. Two ...

  5. Presencia de Hydrochoerus hydrochaeris (Hydrochoeridae, Rodentia, Mammalia en la cuenca del río Carcarañá, Santa Fe, Argentina: Comentarios acerca de su conservación y biogeografía en Argentina

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    Pablo G. Rimoldi

    2014-01-01

    Full Text Available El carpincho (Hydrochoerus hydrochaeris es el roedor actual más grande del mundo y uno de los mamíferos típico de las Provincias Fitogeográficas Pampeana y del Espinal, habitando todo el sector Este de las mismas. Estas regiones han sido categorizadas por la World Wildlife Foundation (WWF como áreas "en peligro crítico/ amenazada", y se les asigna el nivel de máxima prioridad de conservación como consecuencia de la destrucción de hábitat, la sobreexplotación, la contaminación y la introducción de especies exóticas. El carpincho presenta una preferencia marcada por los ambientes con abundancia de cuerpos de agua donde la vegetación palustre le proporciona alimento y refugio. De esta forma, tanto los cuerpos de agua como la vegetación asociada es determinante para la prevalescencia de poblaciones de carpinchos en un ambiente determinado. Para la provincia de Santa Fe los registros no son muy abundantes, registrándose hasta la actualidad unos 33 puntos de colecta/observación, la gran mayoría ubicados en el centro y norte de la provincia. El objetivo de la presente contribución es presentar nuevos registros de presencia de Hydrochoerus hydrochaeris en la cuenca del río Carcarañá (sur de la provincia de Santa Fe, y su asociación con algunas variables climático-ambientales y evaluar la distribución de esta especie. Finalmente, se discute la posible expansión o migración de este especie hacia el oeste de esta provincia y de la provincia de Buenos Aires.

  6. Endogenous development, pathogenicity and host specificity of Eimeria cahirinensis Couch, Blaustein, Duszynski, Shenbrot and Nevo, 1997 (Apicomplexa: Eimeriidae) from Acomys dimidiatus (Cretzschmar 1826) (Rodentia: Muridae) from the Near East.

    Science.gov (United States)

    Kvicerová, Jana; Ptácková, Pavla; Modrý, David

    2007-01-01

    Eimeria cahirinensis Couch et al. 1997 was found in faecal samples of Acomys dimidiatus from three different localities in the Near East. Twenty-two of 104 (21%) A. dimidiatus trapped on both the south- and north-facing slopes of "Evolution Canyon", Lower Nahal Oren, Mt. Carmel, Israel in August 2001 and 2002 were infected with E. cahirinensis. Oocysts were also obtained from a single individual of A. dimidiatus trapped in Wadi Ramm, Jordan in the summer of 1999. Laboratory-reared spiny mice (Acomys spp.) were inoculated to determine the prepatent and patent period, sporulation time, site of infection, immunogenicity, pathogenicity, pathology and morphology of endogenous stages of E. cahirinensis. Both asexual and sexual stages were localised in the apical part of duodenal and jejunal villi. An experimental inoculation of representatives of several rodent genera revealed the host range of E. cahirinensis to be limited to the genus Acomys.

  7. 云南洱海周边地带社鼠体表寄生虫的群落组成%Ectoparasite Communities of Niviventer confucianus ( Rodentia:Muridae) in the Surrounding Areas of Erhai Lake in Yunnan

    Institute of Scientific and Technical Information of China (English)

    董文鸽; 郭宪国; 门兴元; 钱体军; 吴滇

    2009-01-01

    Objective Niviventer confucianus (Milne-Eawards 1871) is the oriental species, not only have been believed to be an important pest for agriculture and forest hut also have been suspected the reservoir of plague, scrub typhus and epidemic hemorrhagic fever (EHF) in the wild rodent-type plague focus of northwestern Yunnan province. This study is aimed to understand the diversity of ectoparasites in a population of Niviventer confucianus in the Surrounding areas of Erhai Lake. Ectoparasite communities of 89 Niviventer confucianus were studied. Methods Different oriented areas surrounding the Erhai Lake in Yunnan were selected as investigation spots. Small mammals were randomly captured with baited mouse cages and ectoparasites were collected form the animals. Ectoparasites were identified to species under a microscope. The constituent ratio(C), prevalence (P) and average ectopaxasite abundance (A) were used to determine the prevalence and density of ectoparasites. Non-parametric Mann-Whitney U-tests were used to test differences in the abundance and richness of ectoparasites between female and male hosts. Spearman correlation analysis was used to analyze the relationship between ectoparasites and the body parameters of hosts. Results There is very high diversity of ectoparasites of Niviventer confucianus and some species of ectoparasites have been reported associated with human disease. A high proportion (79%) of 70 Niviventer confucianus was found to be infested with ectoparasites. A total of 51 species of ectoparasites, including 31 species of chigger mite, 13 species of mesostigmatid (gamasid) mite, 4 species of flea and 3 species of sucking louse were collected. Walchia ewingi fuller is the most abundant chigger mite species, accounting for 66.23% of all chigger mites. Laelaps turkestanicus lange is the most abundance gamasid mite species, accounting for 38.48% of all gamasid mites. Paradoxopsyllus custodies Jordan was the most abundance of the fleas observed, accounting for 42.86% of all fleas collected. Hoplopleurapacifica was the most abundance of the sucking lice observed, accounting for 80.07% of all sucking lice collected. Within this ectoparasite complex, 11 species have previously been reported to be vectors of human diseases. Non-parametric Mann-Whitney U-tests showed the species richness and abundance of total ectoparasites, chigger mites, sucking lice, fleas or gamasid mites had no significant differences between male and female hosts. Spearman correlation analysis showed that abundance and species of total ectoparasite, chigger mite, sucking louse, flea or gamasid mite were not correlated with the body weight of the host. Conclusions The community structure of ectoparasites of Niviventer confucianus is complex, which reflects a high species diversity of ectoparasites on Niviventer confucianus. 11 species have previously been reported to be vectors of human diseases. Sucking lice, fleas, chiggers and gamasid mites are main ectoparasites. Niviventer confucianus would be a natural reservoir for pathogen on plague bacilli, epidemic haemorrhagic fever (korean haemorrhagic fever) viruses, and scrub typhus.%目的 社鼠是东洋界种,不仅一直被认为是农林业有害动物.而且被怀疑为滇西北鼠疫疫源地的鼠疫、恙虫病和流行性出血热(汉坦病毒)等病原体的储存宿主.为了了解洱海周边地带社鼠体表寄生虫的多样性,我们研究了89只社鼠体表寄生虫的群落组成.方法 选取云南洱海周边的不同地理方位作为野外抽样调查地点,用鼠笼加食饵诱捕小兽并检获其体表寄生虫.体表寄生虫在显微镜下鉴定寄生虫的种类.用染虫率和虫指数反映体表寄生虫的流行和密度状况,用统计分析中的非参数检验(Non.parametric Mann.Whitney U)分析雌雄小兽宿主间寄生虫数量差异.用Spearman相关分析(Spearman correlation analysis)体表寄生虫数量与宿主身体参数的关系.结果 捕获89只社鼠.其中70只社鼠侵染体表寄生虫,总侵染率为79%.采集到体表寄生虫51种,包括31种恙螨、13种革螨、4种蚤及3种吸虱.攸氏无前恙螨为优势恙螨种,占恙螨总数的66.23%;土尔克厉螨为优势革螨种,占革螨总数的38.48%;绒鼠怪蚤为优势蚤种,占蚤总数的42.86%;太平洋甲胁虱为优势吸虱种,占吸虱总数的80.07%.这51种体表寄生虫中,有11种被证明是人类疾病的主要媒介.U检验表明,体表寄生虫、恙螨、吸虱、蚤类和革螨的个体数量和物种数在雌雄宿主体表间的差异无统计学意义.spearman相关分析表明,体表寄生虫、恙螨、吸虱、蚤类和革螨的个体数量与宿主身体参数(体重)之间无相关性.结论 社鼠的体表寄生虫群落结构复杂,物种多样性高,其中有11种曾经报道与人类疾病有关.社鼠主要的体表寄生虫为吸虱、蚤类、革螨和恙螨,社鼠很可能成为鼠疫、流行性出血热和灌丛斑疹伤寒等病原体的贮存宿主.

  8. INVESTIGATION ON RELATIVE DENSITY OF RODENTIA AND INSECTIVORA IN MT EMEI IN AUTUMN%峨眉山啮齿类和食虫类秋季相对密度调查

    Institute of Scientific and Technical Information of China (English)

    康明江; 苗苗; 王晓琴; 胡锦矗

    2003-01-01

    2002年9月28日~10月6日,主要用铗日法对四川峨眉山啮齿类和食虫类进行调查,得出以下结论:被捕的20种中,相对密度较大的为高山姬鼠(Apodemus chevrieri)占26.09%、龙姬鼠(Apodemus draco)占18.26%、长尾姬鼠(Apodemus sylvaticus)占15.65%及四川短尾鼩(Anourosorex squamipes)占10.43%;在5个典型生境样点中,金顶(15.33%)、雷洞坪(20.99%)和仙峰寺(13.95%)3处的兽类相对密度较大,但清音阁(1.01%)和报国寺(0)二处的相对密度很小,导致其显著差异的具体原因尚不清楚,有待进一步研究.

  9. DIPODIDAE (RODENTIA, MAMMALIA) FROM THE MID-TERTIARY DEPOSITS IN DANGHE AREA, GANSU, CHINA%甘肃党河地区第三纪中期的跳鼠化石

    Institute of Scientific and Technical Information of China (English)

    王伴月

    2003-01-01

    描述了产自甘肃省党河地区第三纪中期的跳鼠化石3属7种.其中5种(Parasminthusasiae-centralis,P.tangingoli,P.parvulus,Heterosminthus lanzhouensis和Litodonomys cf L.huang-heensis)产自狍牛泉组上部,时代为晚渐新世.产自早中新世(?)铁匠沟组中部的2种是中间异蹶鼠(新种)(Heterosminthus intermedius sp.nov.)和西水简齿鼠(新种)(Litodonomys xishuiensissp.nov.).Heterosminthus intermedius的主要特征是:M2的前齿带较短而低,ml的下次脊较向前斜伸,与下中尖前的下外脊相连;在颊齿的宽窄比例和其他一些特征上介于H.orientalis和H.lanzhouensis之间.Litodonomys xishuiensis的主要特征为:下臼齿比例上较宽短,下外脊位于纵中线附近;下中脊在m1中长,在m2中无;m2和m3下前边尖很发育,但孤立;m3下中凹和下外凹明显缩短等.探讨了Heterosminthus和Litodonomys的进化趋势和铁匠沟组中部的时代.

  10. Evolución de los géneros Mimomys, Arvicola y Allophaiomys (Arvicolidae, Rodentia, Mammalia en el Plioceno y Pleistoceno de la Península Ibérica

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    Ruiz Bustos, A.

    1985-04-01

    Full Text Available A new interpretation of the philogeny of the arvicolids Mimomys, Arvicola and Allophaiomys is proposed in this paper as a result of the comparison between several faunas of the Pliocene and lower and middle Pleistocene of the Iberian Península.
    The morphologic study of the abundant populations of Mimomys of the Pliocene bed from Moreda, has made it possible to establish, for each species, four divisions according to the stages of wear of the first lower molar. The evolution of Mimomys is closely related to the qualitative and quantitative variations of those stages of wear (from the most primitive to the most progressive ones in the course of the time and for each different populations of Mimomys, which leads us to propose the following scheme of the evolution of the genus: During the Pliocene, two evolutionary lines of Mimomys are present since the appearance of the genus in the Iberian Peninsula: one of small size, in which the acquisition of cement in the molars is progressive, That one is represented by the following evolutionary stages: M. stehlini in the Ruscinian and M. pliocaenicus-M, medasensis in the upper Pliocene. the other line, of big size, is represented by M. cappettai and the cement in the molars exists already in the niore primitive populations. At the end of the Pliocene appears M. reidi of small size, By its similar morphology, the latter species is very probably the ancestor of the bigger M. savini that belongs to the lower and middle Pleistocene. On the other hand, the morphologic identity and the biometric proximity of Allophaiomys chalinei to the populationsof small size of Arvicola (A. mosbachensis, leads us to propose the evolutionary line: Arvicola deucalion-Arvicola chalinei-Arvicola mosbachensis. Therefore, Mimomys is an independent and coetaneus genus of Arvicola that disappeared in the upper Pleistocene. Finally, Allophaiomys pliocaenicus gives rise to Microtus and Pitymys by a cladogenetic process of diversification.

    En el presente trabajo se propone una nueva interpretación de la filogenia de los arvicólidos Mimomys, Arvicola y Allophaiomys como resultado de la comparación de diversas faunas del Plioceno y Pleistoceno inferior y medio de la Península Ibérica.
    El estudio morfológico de las abundantes poblaciones de Mimomys del yacimiento Plioceno de Moreda, ha permitido, para cada especie, su división en cuatro estadios de desgaste! del primer molar inferior. La evolución de Mimomys está estrechamente relacionada con la variación cualitativa y cuantitativa de dichos estadios de desgaste (de los más primitivos a los más progresivos a lo largo del tiempo en el seno de las diferentes poblaciones de Mimomys , lo cual nos lleva a proponer el siguiente esquema. de la evolución del género: Durante el Plioceno, dos líneas evolutivas de Mimomys están presentes desde la aparición del género en la Península Ibérica: una de pequeña talla en la que la adquisición de cemento en los molares es progresiva y que está representada por los estadios evolutivos: M. stehlini en el Rusciniense y M. pliocaenicus - M. medasensis en el Plioceno superior. Y otra línea de gran talla representada por M. cappettai en la que el cemento en, los molares existe ya en las poblaciones más primitivas. Al final del Plioceno aparece M. reidi, de pequeña talla, que, por su semejanza morfológica, es muy probablemente el antecesor de M. savini, de mayor talla, del Pleistoceno inferior y medio.
    Por otra parte, la identidad morfológica y la proximidad biométrica de Allophaiomys deucalion y Allophalomys chalinei con las poblaciones de pequeña talla de Arvicola del Pleistoceno medio (Arvicola mosbachensis, nos llevan a proponer la línea evolutiva: Arvicola deucalion-Arvicola chatinei-Arvicola mosbachensis. Así pues, Mimomys es un género independiente y coetáneo de Arvicola que se extingue durante el Pleistoceno superior.
    Finalmente, Allophalomys pliocaenicus dará lugar por un proceso cladogenético de diversificación a Microtus y Pitymys.

  11. DOĞU KARADENİZ BÖLGESİNDE YAYILIŞ GÖSTEREN APODEMUS KAUP, 1829 (MAMMALIA: RODENTIA) CİNSİNİN MORFOLOJİK ANALİZİ

    OpenAIRE

    2007-01-01

    Bu çalışmada Doğu Karadeniz bölgesinden örneklenen Apodemus cinsine ait 126 örneğin kafatası ve postları değerlendirildi. Diş, kafası ve post örneklerinin yapılan morfolojik analizleri sonucunda bu cinse ait dört tür; Apodemus uralensis, Apodemus flavicollis, Apodemus iconicus ve Apodemus mystacinus belirlendi. Bu türlerden A. flavicollis ve A. iconicus morfolojik açıdan büyük benzerlik gösterirken, A. uralensis’ inde bu iki türe olan yakınlığı yapılan morfolojik ve biyometrik analizler so...

  12. Redescription of Heligmosomoides neopolygyrus, Asakawa and Ohbayashi, 1986 (Nematoda: Heligmosomidae) from a Chinese rodent, Apodemus peninsulae (Rodentia: Muridae); with comments on Heligmosomoides polygyrus polygyrus (Dujardin, 1845) and related species in China and Japan.

    Science.gov (United States)

    Massoni, J; Durette-Desset, M C; Quéré, J P; Audebert, F

    2012-11-01

    Heligmosomoides neopolygyrus, Asakawa and Ohbayashi, 1986 (Nematoda, Heligmosomoidea) is redescribed from Apodemus peninsulae from Rangtang, Sichuan, China. A morphological review of the Heligmosomoides spp. belonging to the "polygyrus line" proposed by Asakawa (1988) is made using new characters. This enabled us to distinguish two subspecies in Mus musculus (Heligmosomoides polygyrus bakeri from Japan and H. p. polygyrus from China) and two valid species in Apodemus spp. (H. neopolygyrus from Japan (in A. peninsulae) and from China (in A. agrarius) and H. asakawae from China (in A. uralensis)). Three parasite species of A. agrarius and A. peninsulae, previously identified by Asakawa et al. (1993) as H. neopolygyrus, are considered to be Heligmosomoides incertae sedis. This is the first report of H. neopolygyrus in A. peninsulae from China.

  13. EOMYIDS (MAMMALIA: RODENTIA) FROM THE LATE MIOCENE LUFENG AND YUANMOU HOMINOID LOCALITIES, YUNNAN%云南禄丰、元谋晚中新世古猿地点始鼠科化石

    Institute of Scientific and Technical Information of China (English)

    邱铸鼎

    2006-01-01

    The material which forms the basis of this study was collected from two hominoid localities,Shihuiba of Lufeng and Leilao of Yuanmou, in Yunnan Province in the last twenty years. Five forms of eomyid rodents, Plesieomys mirabilis gen. et sp. nov. , Heteroeomys yunnanensis gen. et sp. nov. , Leptodontomys pusillus sp. nov., Leptodontomys sp. and Eomyidae gen. et sp. indet, are now recognized in the two late Miocene faunas. Morphologically, Plesieomys n. gen. shows some similarities to Pseudadjidaumo Lindsay, 1972 of North America, but the phylogenetic relationship of the new genus to the American genus is uncertain. Heteroeomys exhibits a mixture of primitive and advanced dental features of bunodont eomyids and might be descended from an early Eomys species. Leptodontomys pusillus is characterized by its smaller size, weaker developed lingual anteroloph on M1/2, narrow anterolophid and poor mesolophid and hypolophid on m1/2. The eomyid record in Yunnan indicates that eomyid rodents are a wideranging family in Asia, and that forested habitats are preferred more by eomyids with bunodont cheekteeth than by eomyids with lophodont cheek-teeth.

  14. Experimental evidence and ecological perspectives for the adaptation of Schistosoma mansoni Sambon, 1907 (Digenea: Schistosomatidae to a wild host, the water-rat, Nectomys squamipes Brants, 1827 (Rodentia: Sigmodontinae

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    Paulo Sérgio D'Andrea

    2002-10-01

    Full Text Available Due to the semi aquatic habits and the overlap of the geographical distribution of the water-rat, Nectomys spp., with schistosomiasis endemic areas, these wild rodents are very likely to acquire Schistosoma mansoni infection in their daily activities. The role of the water-rat in the S. mansoni cycle would be substantiated if one could prove that these rodents acquire the parasite during their own activity time, a completely independent time schedule of human activities. To pursue this goal, we performed two field experiments in the municipality of Sumidouro, State of Rio de Janeiro, Brazil, a schistosomiasis endemic area where N. squamipes is found naturally infected. One experiment was devised as a series of observations of activity time of the water-rat. The other experiment was a test of the occurrence of late transmission of S. mansoni to the water-rat. The daily activity pattern showed that the water-rat is active chiefly just after sunset. At both diurnal and late exposition essays the water-rat sentinels got infected by S. mansoni. These findings clarify ecological and behavioral components necessary to the adaptation of S. mansoni to the water-rat as a non human definitive host and the existence of a transmission cycle involving this animals as a reservoir.

  15. Parasites of mammals on the Sevilleta National Wildlife Refuge, Socorro, New Mexico: Cuterebra austeni and C. neomexicana (Diptera:Oestridae) from Neotoma and Peromyscus (Rodentia:Muridae), 1991-1994.

    Science.gov (United States)

    Wilson, W D; Hnida, J A; Duszynski, D W

    1997-05-01

    In total, 6,486 rodents representing 3 families (Muridae, Heteromyidae, and Sciuridae) and 24 species were trapped May through August of 1991 through 1994. Of these, only the white-throated woodrat. Neotoma albigula Hartley; piñon mouse, Peromyscus truei Shufeldt; and white-footed mouse, P. leucopus Rafinesque, were infested with Cuterebra Clark larvae. Of the 594 N. albigula that were captured 103 (17.3%) were infested with 139 Cuterebra larvae with all infestations occurring in the throat region. N. albigula infestations were observed in 4 of 5 habitats sampled. The highest prevalence of infestation occurred during May-June (27.2%) versus July-August (9.1%) and in males (25.2%) versus females (18.3%). Prevalence of infestation was not significantly different between animals from the mark-release webs versus removal webs or adults versus juveniles. Also, there was no correlation between relative density of N. albigula and prevalence of infestation. Fifteen adults were reared from puparia and identified as C. austeni Sabrosky. Of 716 P. truei captured, 22 (3.1%) were infested with a total of 25 Cuterebra larvae with all infestations occurring in the scapular region. Although P. truei were captured in all 5 habitats, they were only infested in the piñon-juniper habitat: the highest prevalence of infestation occurred during July-August (10.9%) versus May-June (3.3%). Prevalence of infestation was not significantly different between animals from mark-release webs versus removal webs, males versus females, or adults versus juveniles. As in the N. albigula, there was no correlation between relative density of P. truei and prevalence of infestation. The adult reared from a puparium was identified as C. neomexicana Sabrosky. Of the 310 P. leucopus captured, only 3 (1%) were infested with Cuterebra larvae.

  16. First report of Siphonaptera infesting Microtus (Microtus cabrerae (Rodentia-Muridae-Arvicolinae in Cuenca , Spain and notes about the morphologic variability of Ctenophthalmus (Ctenophthalmus apertus personatus (Insecta-Siphonaptera-Ctenophthalmidae

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    Gómez M.S.

    2003-06-01

    Full Text Available The fleas infesting Microtus (Microtus cabrerae from three different areas of Cuenca province (Spain have been studied. It is the first time that an ectoparasitological study of this badly known rodent has been done. Four Siphonaptera species have been detected : Rhadinopsylla (Actenophthalmus pentacantha, Peromyscopsylla spectabilis spectabilis, Nosopsyllus fasciatus and Ctenophthalmus (Ctenophthalmus apertus personatus, which was the most abundant species (26 males and 31 females of a total of 28 males and 35 females. Considering the great morphologic variability within the male processus basimerus ventralis (p.b.v. of segment IX of C. personatus subspecies, three morphotypes have been recognised. The male polymorphism detected, would be the result of both host confinement and genetic selection acting on the parasite. It should be pointed out that C. (C. apertus personatus is not narrowly host-specific, therefore further studies are required to clarify this taxonomic situation.

  17. Caracterización molecular y cariológica de cuatro especies del Género Proechimys (Rodentia: echimyidae, en una colonia en cautiverio en el Instituto Nacional de Salud (Colombia

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    Fernando García Luis

    2004-12-01

    Full Text Available En el presente trabajo se realizó la caracterización cariológica y molecular de cuatro especies pertenecientes al género Proechimys, las cuales fueron colectadas en diferentes regiones de Colombia y posteriormente ubicadas en colonias en el Bioterio de Experimentación del Instituto Nacional de Salud-INS. El número estimado de especies varía según el criterio de diferentes autores lo cual reflejan la gran dificultad para establecer límites en Proechimys a sus taxones subordinados. En general, los caracteres morfológicos son la aproximación usual para evaluar las preguntas sistemáticas por la mayoría de mastozoólogos, pero ésto ha sido relativamente improductivo en Proechimys. Como consecuencia de las variaciones morfológicas presentadas en los individuos, varios autores se han centrado sobre este aspecto, buscando la manera más adecuada de establecer diferencias entre las especies y han recurrido a técnicas de tipo genético y molecular que
    permitan esclarecer la separación específica de los grupos. Para este trabajo la caracterización cariológica se llevó a cabo a partir de la técnica de cultivo de linfocitos de sangre periférica. La caracterización molecular se realizó a partir de un fragmento de 800 pares de bases del gen Citocromo B. Para la construcción de los árboles se utilizaron otras secuencias para Proechimys, disponibles en Genbank y se incluyeron secuencias suministradas, en calidad de préstamo, por el Doctor James Patton de la Universidad de California, Berkeley. Se confirmó, por medio de información cariológica y molecular, que los individuos de la colonia del INS pertenecen a cuatro especies diferentes las cuales fueron identificadas como: Proechimys chrysaeolus (departamento de Santander, P. sp. “Barinas” (departamento de Casanare, P. oconnelli (departamento de Casanare y P. canicollis (departamento de La Guajira. Los tiempos de divergencia obtenidos para las especies (entre 2,89
    MA y 5,92 MA se aproximan al Mioceno, época en la cual se presume que Proechimys evolucionó en la Amazonia. Tres de las cuatro especies de este estudio son incluidas dentro de los grupos propuestos por Patton (1987: P. chrysaeolus, grupo trinitatus, P. canicollis, grupo canicollis (monotípico y P. oconnelli, grupo semispinosus. La forma nominal P. sp. “Barinas” no es referida por este autor.

  18. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877 – Rodentia, Echimyidae – population with varying jackfruit tree (Artocarpus heterophyllus L. abundances

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    JHF Mello

    Full Text Available We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i to calculate the carrying capacity K based on real data of the involved species and the environment; ii propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  19. Identidade, riqueza e abundãncia de pequenos mamíferos (Rodentia e Didelphimorphia de área de Floresta com Araucária no estado do Paraná, Brasil

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    Guilherme Grazzini

    2015-01-01

    Full Text Available Roedores e Marsupiais são componentes importantes da fauna na região Neotropical. Estudos sobre a riqueza e abundância destes animais são raros na Floresta Ombrófila Mista (FOM e aqui apresentamos um inventário conduzido na Floresta Nacional de Piraí do Sul. Esta área possui uma área aproximada de 150 ha, cercada por pastos e plantações de Pinus. A amostragem foi feita através de armadilhas de queda, Sherman e Tomahawk, dispostas nos principais tipos de vegetação encontrados. Pelo menos um casal de cada espécie foi coletado. Como resultado, durante 5.892 armadilhas.noite nós obtivemos um total de 1.049 capturas, representando 17 espécies: Akodon montensis, Bibimys labiosus, Brucepattersonius iheringi, Cryptonanus sp., Didelphis albiventris, D. aurita, Gracilinanus microtarsus, Monodelphis americana, M. scalops, Myocastor coypus, Nectomys squamipes, Oligoryzomys nigripes, Oxymycterus judex, O. nasutus, Sooretamys angouya e Thaptomys nigrita. Capturas por armadilhas de queda representaram 67% do total, e oito espécies foram registradas exclusivamente por este método. Akodon montensis, O. nigripes e T. nigrita foram as espécies mais abundantes.

  20. Gastrointestinal helminths (Cestoda, Chabertiidae and Heligmonellidae) of Pogonomys loriae and Pogonomys macrourus (Rodentia: Muridae) from Papua Indonesia and Papua New Guinea with the description of a new genus and two new species.

    Science.gov (United States)

    Smales, L R

    2014-11-28

    Pieces of cestode, not indentified further, and 12 species of nematode including 1 new genus, 3 new species and 7 putative new species from the Families Chabertiidae and Heligmonellidae were collected from the digestive tracts of 16 Pogonomys loriae and 19 P. macrurous (Murinae: Hydromyini) from Papua, Indonesia and Papua New Guinea. The chabertiid Cyclodontostomum purvisi and the heligmonellid Odilia mackerrasae have been described previously from endemic murids. Hasanuddinia pogonomyos n. sp. can be distinguished from its congeners by the number of ridges in the synlophe, length of spicules and having a vagina with a dorsal diverticulum. Odilia dividua n. sp. is larger than its congeners, has a longer oesophagus, relatively shorter spicules and larger eggs. Pogonomystrongylus domaensis n. gen., n. sp. differs from all other genera in the Heligmonellidae in the characters of the synlophe, 7-10 ridges oriented sub frontally with a single left ventral ridge hypertrophied. Species richness of the nematode assemblages of P. loriae and P. macrourus are comparable to those of Abeomelomys sevia, Chiruromys vates and Coccymys rummleri when numbers of hosts examined are considered. Species composition was distinctive with 12, including the 7 putative species, of 14 species presently known only from species of Pogonomys. Similarities between the nematode fauna of endemic rodent hosts from Indonesia and Papua New Guinea were noted.

  1. Trichostrongylina (Nematoda, Heligmosomoidea coparasites in Dasyprocta fuliginosa Wagler (Rodentia, Dasyproctidae from Brazil, with the re-establishment of the genus Avellaria Freitas & Lent and the description of two new species Trichostrongylina (Nematoda, Heligmosomoidea co-parasitos em Dasyprocta fuliginosa Wagler (Rodentia, Dasyproctidae do Brasil, com o restabelecimento do gênero Avellaria Freitas & Lent e a descrição de duas novas espécies

    Directory of Open Access Journals (Sweden)

    Marie C. Durette-Desset

    2006-06-01

    Full Text Available Two new tichostrongylid nematodes of the family Viannaiidae Durette-Desset & Chabaud, 1981 coparasites in Dasyprocta fuliginosa Wagler, 1832 from the State of Amazonas, Brazil, are described: Viannella trichospicula sp. nov. is differentiated from the other species of the genus by the extreme slenderness of its spicules. Avellaria intermedia sp. nov. is distinguished from the single type species Avellaria avellari Freitas & Lent, 1934, by a smaller number of cuticular ridges (17 versus 27, a higher ratio of spicule length/ body length (8% versus 5.6% and spicules with a single tip. This genus, synonymized with the genus Viannella Travassos, 1918, by Durette-Desset (1968 is re-established, the female being didelphic. It is the first record of a nematode of the family Viannaiidae in a host of the family Dasyproctidae Bonaparte, 1838.Dois novos nematóides tricostrongilídeos da família Viannaiidae Durette-Desset & Chabaud, 1981 co-parasitos em um espécime de Dasyprocta fuliginosa Wagler, 1832 do Estado do Amazonas, Brasil, são descritos: Viannella trichospicula sp. nov. distingue-se das espécies do gênero, pelos espículos extremamente delgados. Avellaria intermedia sp. nov. diferencia-se da espécie tipo e única do gênero Avellaria avellari Freitas & Lent, 1934, pelo menor número de arestas cuticulares (17 comparado a 27, pela maior relação entre o tamanho do espículo e o comprimento do corpo (8% comparado a 5,6% e espículos com extremidade única. Este gênero, que havia sido considerado sinônimo de Viannella Travassos, 1918, por Durette-Desset (1968, é restabelecido; as fêmeas são didelfas. Este é o primeiro registro de um nematóide da família Viannaiidae em um hospedeiro da família Dasyproctidae Bonaparte, 1838.

  2. Patrones de distribución geográfica de la riqueza de especies de roedores de la tribu Oryzomyini (Rodentia: Sigmodontinae en Sudamérica: Evaluando la importancia de los procesos de colonización y extinción Geographic patterns of richness distribution of rodents species from the Oryzomyini tribe (Rodentia: Sigmodontinae in South America: Evaluating the importance of colonization and extinction processes

    Directory of Open Access Journals (Sweden)

    EVELYN VALENCIA-PACHECO

    2011-09-01

    Full Text Available La tribu de roedores Oryzomyini es la más diversa dentro de la subfamilia Sigmodontinae. Está constituida por 120 especies y 31 géneros, de las cuales 83 son endémicas del continente sudamericano. Este grupo exhibe una extensa distribución que abarca toda la región Neotropical, caracterizada por la presencia de una mayor riqueza en la Amazonia con una disminución monotónica hacia el sur y norte de Sudamérica. Este es un patrón bastante conocido en la mayoría de los taxones, por lo que se han propuesto varios mecanismos causales. Sin embargo, se desconocen los mecanismos que dan cuenta de este gradiente latitudinal en la riqueza de especies de Oryzomyini. Debido a que estas especies son originarias de la Amazonia, y que a través de su historia colonizaron ambientes nuevos y más variables (sur y norte, se evaluó la hipótesis fuente-sumidero, mediada por procesos de colonización y extinción, como potencial explicación al patrón de riqueza observado. Para evaluar esta hipótesis se reunió una base de datos de distribución y riqueza de especies por grado de latitud para todo el continente sudamericano. Posteriormente se evaluó el grado de anidamiento mediante los índices de T (temperatura, BR (discrepancia y NODF. Nuestros resultados evidenciaron un grado de anidamiento significativo en la distribución de Oryzomyini, y un anidamiento significativo separadamente en filas y columnas de la matriz. Por lo tanto, se concluye que la dinámica fuente-sumidero afecta el patrón de distribución de la riqueza de roedores Oryzominos, a través de un proceso de colonización durante su expansión en Sudamérica que fue mediado por los rangos de tolerancia de las especies. Finalmente, las especies menos tolerantes se habrían extinguido, lo que determinaría un menor número de especies hacia el sur y norte de la Amazonia.The Oryzomyini rodent tribe is the most diverse taxon within the Sigmodontinae subfamily. This tribe includes 120 species and 31 genera, of which 83 are endemic to the South American continent. This tribe presents a wide distribution, covering the entire Neotropical biogeographic province, and is characterized by the presence of greater richness in the Amazonian area, with a monotonic decrease towards the south and north of South America. This pattern is well-known in many taxa, for which various causal mechanisms have been proposed. However, the mechanisms that explain this pattern of species richness along the latitudinal gradient in the Oryzomyini tribe are unknown. Given that these species are native to Amazonia, and that throughout their history they colonized new and more variable environments (towards the south and north, we evaluated the source-sink hypothesis, mediated by processes of colonization and extinction, as a potential explanation for the observed pattern of richness. To test this hypothesis we built a database of species' distribution and richness every one degree of latitude for the entire South American continent. Subsequently we assessed the degree of nestedness using the T (temperature, BR (discrepancy and NODF indices. Our results show a significant degree of nesting in the Oryzomyini distribution, and a significant degree of nesting of the rows and columns of the data matrix, separately. Therefore, we conclude that source-sink dynamics affect the pattern of richness distribution of Oryzomine rodents, through a process of colonization during its expansion in South America, which was conditioned by the range of tolerance of the species. This resulted in the extinction of the less tolerant species, which finally resulted in a lower number of species towards the south and north of Amazonia.

  3. Biodiversity of the Sierra del Divisor Zone Reserved (Peru: a view from small mammals

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    César E. Medina

    2015-10-01

    Full Text Available This study documents the small mammalian diversity in the Zona Reservada Sierra del Divisor (ZRSD. Six sites were evaluated between 2011 and 2013 with capture techniques (Victor snap traps, Tomahawk traps, Pitfall traps and mist nets. 67 species of small mammals were recorded (five marsupials, 10 rodents and 52 bats, 32 of which are new records for the ZRSD and two are species of the most rare and endemic rodents of Peru, the “Peruvian Aquatic Rat” Neusticomys peruviensis (Cricetidae: Ichthyomyini and “Ucayali´s Aquatic Mouse” Amphinectomys savamis (Cricetidae: Oryzomyini. On the other hand, the marsupial Marmosops bishopi; rodents Neacomys minutus, Euryoryzomys macconnelli, Scolomys melanops and Proechimys kulinae; and the bats Artibeus planirostris and Rhinophylla pumilio were the most plenty. Our finding showed the importance of the re-categorization of Reserved Zone to National Park like as a significant contribution to the conservation of the Peruvian mammals.

  4. LINE-1 distribution in six rodent genomes follow a species-specific pattern

    Indian Academy of Sciences (India)

    A. Vieira-Da-Silva; F. Adega; H. Guedes-Pinto; R. Chaves

    2016-03-01

    L1 distribution in mammal’s genomes is yet a huge riddle. However, these repetitive sequences were already found in all chromosomic regions, and in general, they seem to be nonrandomly distributed in the genome. It also seems that after insertionand when they are not deleterious, they are always involved in dynamic processes occurring on that particular chromosomic region. Furthermore, it seems that large-scale genome rearrangements and L1 activity and accumulation are somehow interconnected. In the present study, we analysed L1 genomic distribution in Tatera gambiana (Muridae, Gerbillinae), Acomys sp. (Muridae, Deomyinae), Cricetomys sp. (Nesomyidae, Cricetomyinae), Microtus arvalis (Cricetidae, Arvicolinae), Phodopus roborovskii and P. sungorus (Cricetidae, Cricetinae). All the species studied here seems to exhibit a species-specific pattern.Possible mechanisms, and processes involved in L1 distribution and preferential accumulation in certain regions are discussed.

  5. Placentation in Sigmodontinae: a rodent taxon native to South America

    DEFF Research Database (Denmark)

    Favaron, Phelipe O; Carter, Anthony Michael; Ambrosio, Carlos E;

    2011-01-01

    ABSTRACT: BACKGROUND: Sigmondontinae, known as "New World rats and mice," is a large subfamily of Cricetidae for which we herein provide the first comprehensive investigation of the placenta. METHODS: Placentas of various gestational ages ranging from early pregnancy to near term were obtained fo...... subfamily of South American rodents. We note, however, that some of these rodents can be captive bred and recommend that future studies focus on the study of time dated pregnancies....

  6. Spot-on Treatments of Diflubenzuron and Permethrin to Control a Guinea Pig Louse, Gliricola Porcelli (Phthiraptera: Gyropidae)

    Science.gov (United States)

    Guinea pigs (Cavia porcellus (L.)) (Rodentia: Caviidae) are pets and laboratory animals. They can be infested by a chewing louse, Gliricola porcelli (Schrank) (Phthiraptera: Gyropidae), which is fairly common in some animal rearing facilities, pet stores, and on wild guinea pigs. Infestation with G....

  7. Phylogenetic analyses of complete mitochondrial genome sequences suggest a basal divergence of the enigmatic rodent Anomalurus

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    Gissi Carmela

    2007-02-01

    Full Text Available Abstract Background Phylogenetic relationships between Lagomorpha, Rodentia and Primates and their allies (Euarchontoglires have long been debated. While it is now generally agreed that Rodentia constitutes a monophyletic sister-group of Lagomorpha and that this clade (Glires is sister to Primates and Dermoptera, higher-level relationships within Rodentia remain contentious. Results We have sequenced and performed extensive evolutionary analyses on the mitochondrial genome of the scaly-tailed flying squirrel Anomalurus sp., an enigmatic rodent whose phylogenetic affinities have been obscure and extensively debated. Our phylogenetic analyses of the coding regions of available complete mitochondrial genome sequences from Euarchontoglires suggest that Anomalurus is a sister taxon to the Hystricognathi, and that this clade represents the most basal divergence among sampled Rodentia. Bayesian dating methods incorporating a relaxed molecular clock provide divergence-time estimates which are consistently in agreement with the fossil record and which indicate a rapid radiation within Glires around 60 million years ago. Conclusion Taken together, the data presented provide a working hypothesis as to the phylogenetic placement of Anomalurus, underline the utility of mitochondrial sequences in the resolution of even relatively deep divergences and go some way to explaining the difficulty of conclusively resolving higher-level relationships within Glires with available data and methodologies.

  8. Valores hematológicos de capivaras (Hydrochoerus hydrochaeris Rodentia:Hydrochoeridae de vida livre na região de Campinas-SP Capybara's (Hydrochoerus hydrochaeris hematological values free ranging life from Campinas regions, São Paulo state, Brazil

    Directory of Open Access Journals (Sweden)

    Daniela Alves Madella

    2006-08-01

    Full Text Available O objetivo deste estudo foi determinar os valores hematológicos de 14 capivaras de vida livre capturadas nos municípios de Campinas, Monte Alegre do Sul e de São João da Boa Vista. Para a obtenção das amostras de sangue, os animais foram anestesiados via intramuscular, mediante associação de cloridrato de xilazina 2% e cloridrato de ketamina 1%, em doses de 4,5mg/kg/pv e 5,0mg/kg/pv, respectivamente. O sangue foi coletado em tubos contendo EDTA. Para a determinação dos números de eritrócitos e leucócitos, foi utilizada a metodologia tradicional da câmara de Neubauer. O hematócrito foi determinado pelo método de microhematócrito e a hemoglobina pelo método da cianometahemoglobina. Para a contagem diferencial de leucócitos, foi utilizada a técnica de Shilling. Os índices hematimétricos (VCM, HCM E CHCM foram determinados com os valores encontrados na série vermelha. Os resultados da série eritrocitária foram: 4,5 x10(6/miL ± 0,2; hemoglobina: 13.5g/dL ± 0,7; hematócrito: 40,4% ± 2; VCM: 90,2 fL ± 0,9; HCM: 30,1 pg ± 0,7; CHCM: 33,3g/dL ± 1. Na série leucocitária: 5,3 x10³/miL ± 2; bastonetes: 1 % ± 2,1; segmentados: 36,6 % ± 19,9; eosinófilos: 3,5 % ± 11,7; basófilos: 0%; linfócitos: 58,8 % ± 19,6; monócitos: 1,5% ± 2,1. Não foram encontrados os mielócitos e metamielócitos.The purpose of this study was to determine the hematological values of fourteen free life capybaras captured in three cities of São Paulo State, Brazil (Campinas, Monte Alegre do Sul and São João da Boa Vista. Blood samples were obtained with the animals anesthetized through association of 2% xilazine chloridrate and 1% ketamine chloridrate, in the doses of 4.5mg/kg/pv and 5.0mg/kg/pv respectively. The blood was collected using tubes containing EDTA. To determine the number of erythrocytes and leukocytes was used the traditional methodology of the Neubauer chamber. The hematocrit was determined by the microhematocrit method and the hemoglobin by the cianometahemoglobin. For leukocyte differential count the Shilling's method was used. The hematimetric (MCV, MCH and MCHC indexes were determined with the values found in the red serie. The results were: erythrocytes: 4.5 x10(6/mul ± 0.2; hemoglobin: 13.5g/dl ± 0.7; hematocrit: 40.4% ± 2; MCV: 90.2fl ± 0.9; MCH: 30.1pg ± 0.7; MCHC: 33.3g/dl ± 1. In the leukocytes series: 5.3 x10³/mul ± 2; band neutrophil:1 % ± 2.1; segmenter: 36.6 %± 19.9; eosinophils: 3.5% ± 11.7; basophiles: 0%; lymphocytes: 58.8% ± 19.6; monocytes: 1.5% ± 2.1. Myelocytes and metamyelocytes were not found.

  9. Allozyme Polymorphism and Genetic Differentiation Among Populations of Jaculus jaculus and J.orientalis (Rodentia:Dipodidae)in Tunisia%突尼斯非洲跳鼠(Jaculus jaculus)和埃及跳鼠(J.orientalis)群体的等位酶多态及遗传分化

    Institute of Scientific and Technical Information of China (English)

    Abderraouf Ben Faleh; Adel AB Shahin; Khaled Sai

    2009-01-01

    Genetic variability and divergence among natural populations of Jaculus jaculus and J.orientalis in Tunisia were examined by electrophoretic analysis of 16 enzymatic proteins encoded by 23 genetic loci.Low levels of genetic variability were found among populations Of both species in comparison to those of other rodent and mammal species of which data are available.In J.jaculus populations,the mean level of observed heterozygosity(Hobs)ranged from 0.08 to 0.19,while the mean percenmge of polymorphic loci(P)ranged from 26.2%to 45.2%and the mean number of alleles per locus(A)ranged from 1.1 to 1.4.Nevertheless,the mean values were 0.10 to 0.15,29.3%to 44.1%and 1.1 to 1.7.respectively,for J.onentalls.In addition,populations of the two species have revealed a lower degree of genetic differentiation (Fst=0.0017 fot J.jaculus and 0.0019 for J.orientalis).Moreover,Fst was 0.607,P<0.05 between populations of the two species,indicating that tbey were highly genetically diverged from each other.The present data assures the previous results on the validity of the present taxonomic situation of the two species and emphasis on the effect of geographic factors(environments type and bioclimatic stages)on the genetic structure of both species.%运用16种酶蛋白编码的23个遗传座位对突尼斯非洲跳鼠(Jaculus jaculus)和埃及跳鼠(J.orientalis)自然群体的遗传变异和分化进行了电泳分析.结果表明,与其他啮齿动物等哺乳动物的相关数据比较,发现这两个种群体的遗传变异水平较低.非洲跳鼠群体的观测杂合度(Hobs)为0.08-0.19,多态座位百分比(P)为26.2%-45.2%,每个座何的平均等位基因数(A)为1.1-1.4;埃及跳鼠的Hobs为0.10-0.15,P为29.3%-44.1%,A为1.1-1.7.两个种群体各自的遗传分化程度较低(非洲跳鼠和埃及跳鼠的Fst分别为0.0017和0.0019).而两个种群体间的Fst为0.607(P<0.05),表明两个种之间高度的遗传分化.本研究支持这两个种分类地位的合法性,并强调了地理因素(环境类犁和生物气候阶段)对两个种遗传结构的影响.

  10. Comparative genetics of longevity and cancer: insights from long-lived rodents

    Science.gov (United States)

    Gorbunova, Vera; Seluanov, Andrei; Zhang, Zhengdong; Gladyshev, Vadim N.; Vijg, Jan

    2015-01-01

    Mammals have evolved a dramatic diversity of aging rates. Within the single order of Rodentia maximum lifespans differ from four years in mice to 32 years in naked mole rats. Cancer rates also differ significantly, from cancer-prone mice to virtually cancer-proof naked and blind mole rats. Recent progress in rodent comparative biology, in combination with the emergence of whole genome sequence information, has opened opportunities for the discovery of genetic factors controlling longevity and cancer susceptibility. PMID:24981598

  11. Relaciones biogeográficas de los sistemas montañosos de la Península Ibérica: el caso de los micromamíferos

    OpenAIRE

    Vargas, J. M.; Olivero, J.; Márquez, A.L.; Guerrero, J. C.; Real, R.

    2003-01-01

    In the present paper we analyse the biogeographical relationship between the 12 mountain ranges surrounding the western Mediterranean basin, according to their micromammal fauna (70 species belonging to the orders Erinaceomorpha, Soricomorpha and Rodentia). Using an area classification analysis, we performed a biogeographical regionalization of the study area, and later we characterised the biotic boundaries detected. We also identified the interchanges of species that could have happened bet...

  12. Omega-3 fatty acids reduce the development of preneoplasic lesions

    OpenAIRE

    Henriques,Viviana Teixeira; Dias,Cristina Maria Ganns Chaves; Sylvia do Carmo Castro FRANCESCHINI; Sabarense,Céphora Maria; Neuza Maria Brunoro COSTA; Leite,Jacqueline Isaura Alvarez; Peluzio,Maria do Carmo Gouveia

    2009-01-01

    OBJECTIVE: The purpose of this study was to evaluate the anticancer potential of dietary omega-3 supplementation to reduce induced intestinal preneoplastic lesions in Wistar rats. METHODS: A total of 58 11-week-old male Wistar rats (Rattus norvergicus, albinus variety, Rodentia) were distributed into two groups: a control group (n=25) and an omega-3-treated group (n=28). Aberrant crypt foci were induced by 1,2-dimethylhydrazine. Tissue incorporation of the supplemented omega-3 fatty acids was...

  13. Omega-3 fatty acids reduce the development of preneoplasic lesions Ácidos graxos ômega-3 reduzem o desenvolvimento de lesões pré-neoplásicas

    OpenAIRE

    Viviana Teixeira Henriques; Cristina Maria Ganns Chaves Dias; Sylvia do Carmo Castro Franceschini; Céphora Maria Sabarense; Neuza Maria Brunoro Costa; Jacqueline Isaura Alvarez Leite; Maria do Carmo Gouveia Peluzio

    2009-01-01

    OBJECTIVE: The purpose of this study was to evaluate the anticancer potential of dietary omega-3 supplementation to reduce induced intestinal preneoplastic lesions in Wistar rats. METHODS: A total of 58 11-week-old male Wistar rats (Rattus norvergicus, albinus variety, Rodentia) were distributed into two groups: a control group (n=25) and an omega-3-treated group (n=28). Aberrant crypt foci were induced by 1,2-dimethylhydrazine. Tissue incorporation of the supplemented omega-3 fatty acids was...

  14. Rodent phylogeny revised: analysis of six nuclear genes from all major rodent clades

    Directory of Open Access Journals (Sweden)

    Pupko Tal

    2009-04-01

    Full Text Available Abstract Background Rodentia is the most diverse order of placental mammals, with extant rodent species representing about half of all placental diversity. In spite of many morphological and molecular studies, the family-level relationships among rodents and the location of the rodent root are still debated. Although various datasets have already been analyzed to solve rodent phylogeny at the family level, these are difficult to combine because they involve different taxa and genes. Results We present here the largest protein-coding dataset used to study rodent relationships. It comprises six nuclear genes, 41 rodent species, and eight outgroups. Our phylogenetic reconstructions strongly support the division of Rodentia into three clades: (1 a "squirrel-related clade", (2 a "mouse-related clade", and (3 Ctenohystrica. Almost all evolutionary relationships within these clades are also highly supported. The primary remaining uncertainty is the position of the root. The application of various models and techniques aimed to remove non-phylogenetic signal was unable to solve the basal rodent trifurcation. Conclusion Sequencing and analyzing a large sequence dataset enabled us to resolve most of the evolutionary relationships among Rodentia. Our findings suggest that the uncertainty regarding the position of the rodent root reflects the rapid rodent radiation that occurred in the Paleocene rather than the presence of conflicting phylogenetic and non-phylogenetic signals in the dataset.

  15. Genetic diversity between and within the arenavirus species indigenous to western Venezuela

    Science.gov (United States)

    Fulhorst, Charles F.; Cajimat, Maria N.B.; Milazzo, Mary Louise; Paredes, Hector; de Manzione, Nuris M. C.; Salas, Rosa A.; Rollin, Pierre E.; Ksiazek, Thomas G.

    2008-01-01

    The results of analyses of Z, RNA-dependent RNA polymerase, glycoprotein precursor, and nucleocapsid protein gene sequence data suggested that Guanarito virus was the most common cause of Venezuelan hemorrhagic fever in a 7-year period in the 1990’s and that the evolution of Pirital virus in association with Sigmodon alstoni (Alston’s cotton rat) has occurred at a significantly higher rate than the evolution of Guanarito virus in association with Zygodontomys brevicauda (short-tailed cane mouse) on the plains of western Venezuela. The results of analyses of the primary structures of the glycoproteins of the 8 strains of Guanarito virus isolated from humans suggested that these strains would be highly cross-reactive in neutralization assays. Thus, passive antibody therapy may prove beneficial in the treatment of human disease caused by strains of Guanarito virus that are enzootic in the region in which Venezuelan hemorrhagic fever is endemic. PMID:18586298

  16. Hantavirus infection and habitat associations among rodent populations in agroecosystems of Panama: implications for human disease risk.

    Science.gov (United States)

    Armién, Aníbal G; Armién, Blas; Koster, Frederick; Pascale, Juan M; Avila, Mario; Gonzalez, Publio; de la Cruz, Manuel; Zaldivar, Yamitzel; Mendoza, Yaxelis; Gracia, Fernando; Hjelle, Brian; Lee, Sang-Joon; Yates, Terry L; Salazar-Bravo, Jorge

    2009-07-01

    Hantavirus cardiopulmonary syndrome (HCPS), which is caused by infection with Choclo virus, is uncommon in Panama, yet seropositivity among rural residents is as high as 60%. To clarify the environmental risk factors favoring rodent-to-human transmission, we tested serum from 3,067 rodents captured over a five-year period for antibodies against recombinant N protein of hantavirus by enzyme immunoassay and strip immunoblot. Among 220 seropositive rodents, Oligoryzomys fulvescens, the reservoir of Choclo virus, had the highest overall seroprevalence (23.5%); more abundant rodents (Zygodontomys brevicauda and Sigmodon hirsutus) had lower seroprevalences. In the mixed (combined modern and traditional) productive agroecosystem, the highest seroprevalence was among O. fulvescens captured in residences and in crops grown within 40 meters of a residence, with significantly lower seroprevalence in adjacent pasture and non-productive vegetation. Thus, crop habitats may serve as refugia for invasion into adjacent human residences and suggests several interventions to reduce human infection.

  17. [Presence in a rodent of Chili of the nematode Inglamidinae (sub. fam. nov.) belonging to Amidostomatidae, a family known to be found in mammals of Australia].

    Science.gov (United States)

    Durette-Desset, M C; Denke, M A; Murua, R

    1976-01-01

    The Inglamidinae n. sub-fam., a new sub-family of Amidostomatidae from chilean Cricetidae is described with Inglamidum akodon gen. et sp. n. as the type genus and species. Out of the 23 Akodon captured in the same area, three samples of this nematode have been collected from two different species. These findings confirm that we are dealing with a well-adapted parasite and exclude the possibility of a fortuitous catch or an accidental transfer. This family displays two significant groups of taxonomic characters, including archaic characters such as cephalic structures which unite them to the Amidostomatidae, and on the other hand some more recently elaborated characters such as monodelphism and shape of synlophe and spicules which relate them to the Heligmosoms and more significantly to the line Viannaia-Viannella parasite of South-American Marsupials. We interpret this species as a "parasite of capture" and we assume that very similar species might occur in other endemic Mammals, mostly Marsupials. On a paleobiogeographical point of view this interpretation would make due allowance for postulating that the Amidostomatidae from Mammals have originated during the Secondary concurrently with the Marsupial expansion. These ancestral Nematodes would have given birth to the other Trichostrongyloidea through reduction of buccal cavity, and to the Ancylostomatoidea by further elaboration of buccal apparatus. Contrary to Inglis's hypothesis we are in favour of the genera Globocephaloides and Hypodontus to be assigned to the Globocephalinae and Uncinariinae (Ancylostomatidae) respectively, rather than to the Amidostomatidae. The occurrence of an Amidostomatidae in a South American Cricetidae is somewhat quite unexpected, mostly because this family is known to occur from australian Mammals only and also because the parasited Mammals are the most primitive of the group (Monotremes and Marsupials).

  18. Why can't rodents vomit? A comparative behavioral, anatomical, and physiological study.

    Science.gov (United States)

    Horn, Charles C; Kimball, Bruce A; Wang, Hong; Kaus, James; Dienel, Samuel; Nagy, Allysa; Gathright, Gordon R; Yates, Bill J; Andrews, Paul L R

    2013-01-01

    The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity-key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed.

  19. Clinical aspects of rodent dental anatomy.

    Science.gov (United States)

    Crossley, D A

    1995-12-01

    The order Rodentia is vast, encompassing a large number of species with significant anatomical variations developed during natural adaptation to differing habitats. Many veterinarians have little knowledge of the anatomy of species other than the commoner domestic large herbivores and small carnivores. Clinicians require a basic knowledge of the relevant anatomy of species they are likely to be asked to treat. This article provides sufficient working knowledge of the oral and dental anatomy of those rodents commonly kept as pets to enable veterinarians to interpret clinical and radiographic findings when investigating suspected dental disease.

  20. Lung and hearth nematodes in some Spanish mammals.

    Science.gov (United States)

    Alvarez, F; Iglesias, R; Bos, J; Rey, J; Sanmartin Durán, M L

    1991-01-01

    Thirteen host species belonging to the orders Rodentia, Insectivora and Carnivora from various localities in Galicia (NW Spain) were examined for heart and lung parasites. The following species were found: Parastrongylus dujardini (5.5%) in Apodemus sylvaticus, Crenosoma striatum in Erinaceus europaeus (83%), Angiostrongylus vasorum, Crenosoma vulpis and Eucoleus aerophilus in Vulpes vulpes (3, 3.46 and 0.50%, respectively), Crenosoma taiga in Putorius putorius (100%) and Crenosoma sp. in Meles meles (25%). In Crocidura russula nematode larvae were found (3.3%). Mus musculus, Rattus norvegicus, Rattus rattus, Talpa caeca, Sorex araneus, Genetta genetta and Canis lupus were not parasitized by lung or heart parasites.

  1. Anatomy and Disorders of the Oral Cavity of Rat-like and Squirrel-like Rodents.

    Science.gov (United States)

    Mancinelli, Elisabetta; Capello, Vittorio

    2016-09-01

    The order Rodentia comprises more than 2000 species divided into 3 groups based on anatomic and functional differences of the masseter muscle. Myomorph and sciuromorph species have elodont incisors and anelodont cheek teeth, unlike hystrichomorph species which have full anelodont dentition. Diseases of incisors and cheek teeth of rat-like and squirrel-like rodents result in a wide variety of symptoms and clinical signs. Appropriate diagnostic testing and imaging techniques are required to obtain a definitive diagnosis, formulate a prognosis, and develop a treatment plan. A thorough review of elodontoma, odontoma, and pseudo-odontoma is provided, including treatment of pseudo-odontomas in prairie dogs.

  2. Karyotype composition of some rodents and marsupials from Chapada Diamantina (Bahia, Brasil

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    LG. Pereira

    Full Text Available The Chapada Diamantina (CD is located in Bahia State, between 11-14° S and 41-43° W, being part of the Serra do Espinhaço. The occurrence of different habitats and transition areas permits an interesting mammal fauna composition, with species from different biomes living in sympatry. Species of Didelphimorphia and Rodentia are important members of mammal communities in almost all different habitats, and morphological and cytogenetic characters are important for a correct identification of most of these species. In this work 258 specimens of small mammals from the orders Didelphimorphia (six genera and six species and Rodentia (two families, five Sigmodontinae tribes, nine genera and 11 species were collected during the whole field work (44 nights with traps. Chromosome preparations were obtained from 145 specimens from the species: Marmosops incanus, Gracilinanus microtarsus, Monodelphis domestica, Akodon aff. cursor, Necromys lasiurus, Cerradomys sp., Oligoryzomys fornesi, O. nigripes, O. rupestris, Calomys expulsus, Rhipidomys macrurus, Wiedomys pyrrhorhinus and Thrichomys inermis. Didelphis albiventris, Micoureus demerarae, Thylamys karymii and Nectomys sp. were identified by morphological characters. Most analyzed specimens do not show karyotype variation. However, numerical chromosomic variation was found in two individuals of Akodon aff. cursor (2n = 15 and in one individual of Cerradomys sp. (2n = 51. Structural variation in karyotype was observed in seven individuals of Cerradomys sp., showing one additional pair of metacentric chromosomes.

  3. Seed predation by mammals in forest fragments in Monteverde, Costa Rica.

    Science.gov (United States)

    Chinchilla, Federico A

    2009-09-01

    Few studies have evaluated seed predation in fragmented landscapes, in which lower species diversity is expected to modifying ecological interactions. The rates of seed removal by mammals were investigated in a continuous forest and two fragmented patches of Premontane Tropical Moist Forest, in Monteverde, Costa Rica. The composition of mammalian seed-predators in each site was recorded during 16 months. The removal of four native tree species of experimental seeds: Ocotea valeriana and Ocotea whitei (Lauraceae), Panopsis costaricensis (Proteaceae) and Billia colombiana (Hippocastanaceae) in forest understories was followed during two annual fruiting seasons for each species. Results indicated similar species composition of seed-predators between continuous forest, the largest fragment (350 ha). However the smaller fragment (20 ha), had fewer seed predators. In this fragment, the specialized seed predator Heteromys desmarestianus (Rodentia) was more abundant. Unexpectedly, seed-predation in the two forest fragments and the continuous forest did not differ statistically for any of the seed species. Apparently, the higher abundance of small seed-predators in the fragments was compensated by the absence of medium and large seed-predators, like Agouti paca, Dasyprocta punctata (both Rodentia) and Pecari tajacu (Artiodactyla) recorded in continuous forest. Removal of experimentally-placed seeds was higher when the number of naturally occurring seeds in the sites was lower. This result could best be attributed to differential satiation of seed predators rather than differences in richness or abundance of seed predators.

  4. Discrepancy variation of dinucleotide microsatellite repeats in eukaryotic genomes.

    Science.gov (United States)

    Gao, Huan; Cai, Shengli; Yan, Binlun; Chen, Baiyao; Yu, Fei

    2009-01-01

    To address whether there are differences of variation among repeat motif types and among taxonomic groups, we present here an analysis of variation and correlation of dinucleotide microsatellite repeats in eukaryotic genomes. Ten taxonomic groups were compared, those being primates, mammalia (excluding primates and rodentia), rodentia, birds, fish, amphibians and reptiles, insects, molluscs, plants and fungi, respectively. The data used in the analysis is from the literature published in the Journal of Molecular Ecology Notes. Analysis of variation reveals that there are no significant differences between AC and AG repeat motif types. Moreover, the number of alleles correlates positively with the copy number in both AG and AC repeats. Similar conclusions can be obtained from each taxonomic group. These results strongly suggest that the increase of SSR variation is almost linear with the increase of the copy number of each repeat motif. As well, the results suggest that the variability of SSR in the genomes of low-ranking species seem to be more than that of high-ranking species, excluding primates and fungi.

  5. Species identification key of Korean mammal hair.

    Science.gov (United States)

    Lee, Eunok; Choi, Tae-Young; Woo, Donggul; Min, Mi-Sook; Sugita, Shoei; Lee, Hang

    2014-05-01

    The hair microstructures of Korean terrestrial mammals from 23 species (22 wild and one domestic) were analyzed using light and scanning electron microscopy (SEM) to construct a hair identification key. The hairs were examined using the medulla structures and cuticular scales of guard hairs from the dorsal regions of mature adult animals. All cuticular scale structures in the hair of Rodentia, Lagomorpha, Carnivora and Insectivora showed the petal pattern, and those of Artiodactyla and Chiroptera showed the wave pattern and coronal pattern, respectively. Rodentia, Lagomorpha and Carnivora showed multicellular, and Insectivora and Artiodactyla showed unicellular regular, mesh or columnar in the medulla structures, respectively. Chiroptera did not show the medulla structures in their hair. We found that it is possible to distinguish between species and order based on general appearance, medulla structures and cuticular scales. Thus, we constructed a hair identification key with morphological characteristics from each species. This study suggests that hair identification keys could be useful in fields, such as forensic science, food safety and foraging ecology.

  6. In vivo detection of human TRPV6-rich tumors with anti-cancer peptides derived from soricidin.

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    Chris V Bowen

    Full Text Available Soricidin is a 54-amino acid peptide found in the paralytic venom of the northern short-tailed shrew (Blarina brevicauda and has been found to inhibit the transient receptor potential of vallinoid type 6 (TRPV6 calcium channels. We report that two shorter peptides, SOR-C13 and SOR-C27, derived from the C-terminus of soricidin, are high-affinity antagonists of human TRPV6 channels that are up-regulated in a number of cancers. Herein, we report molecular imaging methods that demonstrate the in vivo diagnostic potential of SOR-C13 and SOR-C27 to target tumor sites in mice bearing ovarian or prostate tumors. Our results suggest that these novel peptides may provide an avenue to deliver diagnostic and therapeutic reagents directly to TRPV6-rich tumors and, as such, have potential applications for a range of carcinomas including ovarian, breast, thyroid, prostate and colon, as well as certain leukemia's and lymphomas.

  7. The Stephen H. Long Expedition (1819?1820), Titian R. Peale?s field illustrations, and the lost holotypes of the North American shrews Sorex brevicaudus Say and Sorex parvus Say (Mammalia: Soricidae) from the Philadelphia Museum

    Science.gov (United States)

    Woodman, N.

    2009-01-01

    While encamped for the winter of 1819?1820 at Engineer Cantonment along the Missouri River in present-day eastern Nebraska, members of Major Stephen Harriman Long?s Expedition to the Rocky Mountains collected a number of animals that were previously unknown. Among the mammals were two soricids that were subsequently described by Thomas Say as Sorex brevicaudus (Northern Short-tailed Shrew, Blarina brevicauda) and Sorex parvus (Least Shrew, Cryptotis parvus). The holotypes of these species were deposited and placed on public exhibit in the Philadelphia Museum, the predominant North American systematic collection of the early nineteenth century. Like most private museums of that era, the Philadelphia Museum eventually went out of business, and its collections were dispersed and, for the most part, lost. Fortunately, Titian R. Peale made a detailed field sketch of the two specimens soon after their capture and subsequently executed a watercolor based on that sketch. In addition, an engraving of the holotypes was published in the decade following the discovery of the two species. Illustrations of holotypes are taxonomically useful when they depict diagnostic characters of species. They take on added taxonomic significance in the absence of the holotypes. In the cases of Sorex brevicaudus and Sorex parvus, pictures provide strong confirmation of the taxonomic identities of these two species, as well as recording the early history of the specimens.

  8. Repeated Reticulate Evolution in North American Papilio machaon Group Swallowtail Butterflies.

    Science.gov (United States)

    Dupuis, Julian R; Sperling, Felix A H

    2015-01-01

    Hybridization between distinct populations or species is increasingly recognized as an important process for generating biodiversity. However, the interaction between hybridization and speciation is complex, and the diverse evolutionary outcomes of hybridization are difficult to differentiate. Here we characterize potential hybridization in a species group of swallowtail butterflies using microsatellites, DNA sequences, and morphology, and assess whether adaptive introgression or homoploid hybrid speciation was the primary process leading to each putative hybrid lineage. Four geographically separated hybrid populations were identified in the Papilio machaon species group. One distinct mitochondrial DNA clade from P. machaon was fixed in three hybrid taxa (P. brevicauda, P. joanae, and P. m. kahli), while one hybrid swarm (P. zelicaon x machaon) exhibited this hybrid mtDNA clade as well as widespread parental mtDNA haplotypes from both parental species. Microsatellite markers and morphology showed variable admixture and intermediacy, ranging from signatures of prolonged differential introgression from the paternal species (P. polyxenes/P. zelicaon) to current gene flow with both parental species. Divergences of the hybrid lineages dated to early- to mid-Pleistocene, suggesting that repeated glaciations and subsequent range shifts of parental species, particularly P. machaon hudsonianus, facilitated initial hybridization. Although each lineage is distinct, P. joanae is the only taxon with sufficient evidence (ecological separation from parental species) to define it as a homoploid hybrid species. The repetition of hybridization in this group provides a valuable foundation for future research on hybridization, and these results emphasize the potential for hybridization to drive speciation in diverse ways.

  9. Dieta de murciélagos filostómidos del valle de Kosñipata, San Pedro, Cusco - Perú

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    Rossana Maguiña

    2012-11-01

    Full Text Available En el presente estudio se evaluó la dieta de murciélagos filostómidos de los bosques montanos del valle de Kosñipata (San Pedro, Cusco. Las especies evaluadas pertenecieron a los géneros Carollia, Sturnira y Anoura. Se analizó la dieta en base a la presencia de polen y semillas en muestras fecales. Se realizó un análisis de la importancia de las plantas consumidas, la amplitud del nicho alimenticio y el nivel de superposición del nicho alimenticio. Los resultados mostraron que la dieta de los murciélagos está compuesta en su mayoría por frutos y néctar-polen de las plantas. Los principales recursos registrados pertenecieron a los géneros Piper (registrado en 23,08% de las muestras, Cecropia (en 21,15% y Abutilon (en 13,46%, los cuales fueron los recursos más importantes para la comunidad de murciélagos evaluada. La amplitud de nicho alimenticio para las 6 especies analizadas indicó que son especialistas en su dieta en el área de estudio. Por otro lado, los mayores niveles de superposición de nicho alimenticio ocurre entre las especies C. brevicauda, C. perspicillata y S. erythromos.

  10. A phylogenetic analysis using multidirectional chromosome painting of three species (Uroderma magnirostrum, U. bilobatum and Artibeus obscurus) of subfamily Stenodermatinae (Chiroptera-Phyllostomidae).

    Science.gov (United States)

    Pieczarka, J C; Gomes, A J B; Nagamachi, C Y; Rocha, D C C; Rissino, J D; O'Brien, P C M; Yang, F; Ferguson-Smith, M A

    2013-07-01

    The species of genera Uroderma and Artibeus are medium-sized bats belonging to the family Phyllostomidae and subfamily Stenodermatinae (Mammalia, Chiroptera) from South America. They have a wide distribution in the Neotropical region, with two currently recognized species in Uroderma and approximately 20 species in Artibeus. These two genera have different rates of chromosome evolution, with Artibeus probably having retained the ancestral karyotype for the subfamily. We used whole chromosome paint probe sets from Carollia brevicauda and Phyllostomus hastatus on Uroderma magnirostrum, Uroderma bilobatum, and Artibeus obscurus. With the aim of testing the previous phylogenies of these bats using cytogenetics, we compared these results with published painting maps on Phyllostomidae. The genome-wide comparative maps based on chromosome painting and chromosome banding reveal the chromosome forms that characterize each taxonomic level within the Phyllostomidae and show the chromosome evolution of this family. Based on this, we are able to suggest an ancestral karyotype for Phyllostomidae. Our cladistic analysis is an independent confirmation using multidirectional chromosome painting of the previous Phyllostomidae phylogenies.

  11. Maripa hantavirus in French Guiana: phylogenetic position and predicted spatial distribution of rodent hosts.

    Science.gov (United States)

    de Thoisy, Benoît; Matheus, Séverine; Catzeflis, François; Clément, Luc; Barrioz, Sébastien; Guidez, Amandine; Donato, Damien; Cornu, Jean-François; Brunaux, Olivier; Guitet, Stéphane; Lacoste, Vincent; Lavergne, Anne

    2014-06-01

    A molecular screening of wild-caught rodents was conducted in French Guiana, South America to identify hosts of the hantavirus Maripa described in 2008 in a hantavirus pulmonary syndrome (HPS) case. Over a 9-year period, 418 echimyids and murids were captured. Viral RNA was detected in two sigmodontine rodents, Oligoryzomys fulvescens and Zygodontomys brevicauda, trapped close to the house of a second HPS case that occurred in 2009 and an O. fulvescens close to the fourth HPS case identified in 2013. Sequences from the rodents had 96% and 97% nucleotide identity (fragment of S and M segments, respectively) with the sequence of the first human HPS case. Phylogenetic reconstructions based on the complete sequence of the S segment show that Maripa virus is closely related to Rio Mamore hantavirus. Using environmental descriptors of trapping sites, including vegetation, landscape units, rain, and human disturbance, a maximal entropy-based species distribution model allowed for identification of areas of higher predicted occurrence of the two rodents, where emergence risks of Maripa virus are expected to be higher.

  12. Phylogenetic Relationship of Necoclí Virus to Other South American Hantaviruses (Bunyaviridae: Hantavirus).

    Science.gov (United States)

    Montoya-Ruiz, Carolina; Cajimat, Maria N B; Milazzo, Mary Louise; Diaz, Francisco J; Rodas, Juan David; Valbuena, Gustavo; Fulhorst, Charles F

    2015-07-01

    The results of a previous study suggested that Cherrie's cane rat (Zygodontomys cherriei) is the principal host of Necoclí virus (family Bunyaviridae, genus Hantavirus) in Colombia. Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences in this study confirmed that Necoclí virus is phylogenetically closely related to Maporal virus, which is principally associated with the delicate pygmy rice rat (Oligoryzomys delicatus) in western Venezuela. In pairwise comparisons, nonidentities between the complete amino acid sequence of the nucleocapsid protein of Necoclí virus and the complete amino acid sequences of the nucleocapsid proteins of other hantaviruses were ≥8.7%. Likewise, nonidentities between the complete amino acid sequence of the glycoprotein precursor of Necoclí virus and the complete amino acid sequences of the glycoprotein precursors of other hantaviruses were ≥11.7%. Collectively, the unique association of Necoclí virus with Z. cherriei in Colombia, results of the Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences, and results of the pairwise comparisons of amino acid sequences strongly support the notion that Necoclí virus represents a novel species in the genus Hantavirus. Further work is needed to determine whether Calabazo virus (a hantavirus associated with Z. brevicauda cherriei in Panama) and Necoclí virus are conspecific.

  13. A review of Billaea Robineau-Desvoidy of the eastern Palearctic and Oriental regions (Diptera: Tachinidae).

    Science.gov (United States)

    Zhang, Chun-Tian; Shima, Hiroshi; Wang, Qiang; Tschorsnig, Hans-Peter

    2015-04-23

    The species of Billaea Robineau-Desvoidy (Diptera, Tachinidae) from the eastern Palearctic and Oriental regions are revised. Ten described species are recognized, viz. B. atkinsoni (Baranov) (new records for Japan, Laos, Malaysia, Pakistan and Thailand), B. ficorum (Townsend), B. fortis (Rondani), B. impigra Kolomiets (new record for China), B. kolomyetzi Mesnil, B. malayana Malloch, B. morosa Mesnil, B. robusta Malloch, B. steini (Brauer et Bergenstamm) and B. triangulifera (Zetterstedt) and nine species are described as new to science, B. brevicauda Zhang et Shima sp. nov. (China), B. carinata Zhang et Shima sp. nov. (China), B. chinensis Zhang et Shima sp. nov. (China and Vietnam), B. flava Zhang et Wang sp. nov. (China), B. kurahashii Zhang et Shima sp. nov. (Laos and Thailand), B. micronychia Zhang et Shima sp. nov. (China and Japan; previously misidentified from China as B. irrorata (Meigen)), B. papei Zhang et Shima sp. nov. (Malaysia), B. setigera Zhang et Shima sp. nov. (China) and B. verticalis Shima et Zhang sp. nov. (China). Billaea fasciata (Townsend, 1928) is treated as a junior synonym of B. ficorum (Townsend, 1916), syn. nov. Billaea irrorata is no longer recorded from the eastern Palearctic. A key to 19 species of Billaea from the eastern Palearctic and Oriental regions and 101 figures of male terminalia, bodies, heads and abdomens are given.

  14. Low genetic diversity in pygmy blue whales is due to climate-induced diversification rather than anthropogenic impacts.

    Science.gov (United States)

    Attard, Catherine R M; Beheregaray, Luciano B; Jenner, K Curt S; Gill, Peter C; Jenner, Micheline-Nicole M; Morrice, Margaret G; Teske, Peter R; Möller, Luciana M

    2015-05-01

    Unusually low genetic diversity can be a warning of an urgent need to mitigate causative anthropogenic activities. However, current low levels of genetic diversity in a population could also be due to natural historical events, including recent evolutionary divergence, or long-term persistence at a small population size. Here, we determine whether the relatively low genetic diversity of pygmy blue whales (Balaenoptera musculus brevicauda) in Australia is due to natural causes or overexploitation. We apply recently developed analytical approaches in the largest genetic dataset ever compiled to study blue whales (297 samples collected after whaling and representing lineages from Australia, Antarctica and Chile). We find that low levels of genetic diversity in Australia are due to a natural founder event from Antarctic blue whales (Balaenoptera musculus intermedia) that occurred around the Last Glacial Maximum, followed by evolutionary divergence. Historical climate change has therefore driven the evolution of blue whales into genetically, phenotypically and behaviourally distinct lineages that will likely be influenced by future climate change.

  15. A DNA-based method for identification of krill species and its application to analysing the diet of marine vertebrate predators.

    Science.gov (United States)

    Jarman, S N; Gales, N J; Tierney, M; Gill, P C; Elliott, N G

    2002-12-01

    Accurate identification of species that are consumed by vertebrate predators is necessary for understanding marine food webs. Morphological methods for identifying prey components after consumption often fail to make accurate identifications of invertebrates because prey morphology becomes damaged during capture, ingestion and digestion. Another disadvantage of morphological methods for prey identification is that they often involve sampling procedures that are disruptive for the predator, such as stomach flushing or lethal collection. We have developed a DNA-based method for identifying species of krill (Crustacea: Malacostraca), an enormously abundant group of invertebrates that are directly consumed by many groups of marine vertebrates. The DNA-based approach allows identification of krill species present in samples of vertebrate stomach contents, vomit, and, more importantly, faeces. Utilizing samples of faeces from vertebrate predators minimizes the impact of dietary studies on the subject animals. We demonstrate our method first on samples of Adelie penguin (Pygoscelis adeliae) stomach contents, where DNA-based species identification can be confirmed by prey morphology. We then apply the method to faeces of Adelie penguins and to faeces of the endangered pygmy blue whale (Balaenoptera musculus brevicauda). In each of these cases, krill species consumed by the predators could be identified from their DNA present in faeces or stomach contents.

  16. The identity of the enigmatic "Black Shrew" (Sorex niger Ord, 1815)

    Science.gov (United States)

    Woodman, Neal

    2013-01-01

    The scientific name Sorex niger Ord, 1815 (Mammalia, Soricidae) was originally applied to a North American species that George Ord called the “Black Shrew.” The origin of the name “Black Shrew,” however, was obscure, and Samuel Rhoads subsequently wrote that the species represented by this name could not be determined. The names Sorex niger Ord and Black Shrew have since been mostly forgotten. Two of Ord's contemporaries, however, noted that Ord's use of these names probably alluded to Benjamin Smith Barton's Black Shrew, whose discovery near Philadelphia was announced by Barton in 1806. Examination of two unpublished illustrations of the Black Shrew made by Barton indicates that the animal depicted is Blarina brevicauda (Say, 1822). Had the connection between Ord's and Barton's names been made more clearly, one of the most common mammals in eastern North America would bear a different scientific name today. This connection also would have affected the validity of Sorex niger Horsfield, 1851. While Sorex niger Ord remains a nomen nudum, the animal it referenced can now be identified.

  17. Discovery of hantaviruses in bats and insectivores and the evolution of the genus Hantavirus.

    Science.gov (United States)

    Zhang, Yong-Zhen

    2014-07-17

    Hantaviruses are among the most important zoonotic pathogens of humans, causing either hemorrhagic fever with renal syndrome (HFRS) or hantavirus pulmonary syndrome (HPS). From the period 1964-2006 almost all hantaviruses had been identified in rodents, with the exception of Thottapalayam virus (TPMV) isolated from shrews sampled in India. As a consequence, rodents were considered as the natural reservoir hosts. However, over the past seven years, most of the newly found hantavirus genotypes have been from either shrews or moles. Remarkably, in recent years divergent hantaviruses have also been identified in bats sampled from both Africa and Asia. All these data indicate that hantaviruses have a broad range of natural reservoir hosts. Phylogenetic analyses of the available sequences of hantaviruses suggest that hantaviruses might have first appeared in Chiroptera (bats) or Soricomorpha (moles and shrews), before emerging in rodent species. Although rodent hantaviruses cluster according to whether their hosts are members of the Murinae and Cricetidae, the phylogenetic histories of the viruses are not always congruent with those of their hosts, indicating that cross-species transmission events have occurred at all taxonomic levels. In sum, both cross-species transmission and co-divergence have produced the high genetic diversity of hantaviruses described to date.

  18. Morphological diversity and evolution of the spermatozoon in the mouse-related clade of rodents.

    Science.gov (United States)

    Breed, William G; Leigh, Chris M; Aplin, Ken P; Shahin, Adel A B; Avenant, Nico L

    2014-05-01

    Most species in the three highly speciose families of the mouse-related clade of rodents, the Muridae, Cricetidae, and Nesomyidae (superfamily Muroidea), have a highly complex sperm head in which there is an apical hook but there are few data available for the other related families of these rodents. In the current study, using light and electron microscopies, we investigated the structure of the spermatozoon in representative species of four other families within the mouse-related clade, the Dipodidae, Spalacidae, Pedetidae, and Heteromyidae, that diverged at or near the base of the muroid lineage. Our results indicate that a diverse array of sperm head shapes and tail lengths occurs but none of the species in the families Spalacidae, Dipodidae, or Pedetidae has a sperm head with an apical hook. By contrast, a rostrally extending apical hook is present in spermatozoa of members of the Family Heteromyidae which also invariably have comparatively long sperm tails. These findings suggest that the hook-shaped sperm head in the murid, cricetid, and nesomyid rodents evolved after divergence of this lineage from its common ancestor with the other families of the mouse-related clade, and that separate, and independent, convergent evolution of a similar sperm head form, and long sperm tail, occurred in the Heteromyidae.

  19. Pneumocystis and Histoplasma infections in wild animals from the Amazon region of Brazil.

    Science.gov (United States)

    Lainson, R; Shaw, J J

    1975-01-01

    Routine examination of tissues from wild forest rodents from Amapá, north Brazil, revealed Pneumocystis carinii in lung smears from a newly captured Oryzomys capito (Cricetidae). Acute, fatal infections with this parasite are also recorded in a number of captive "coatimundis", Nasua narica (Carnivora: Procyonidae) and a sloth, Bradypus tridactylus (Edentata). Pneumocystis was also encountered in lung smears from a newly captured and apparently healthy sloth, Choloepus didactylus. The presence of infection in newly captured animals leads us to believe that the fatal, fulminating pneumocystosis seen in the captive Nasua and Bradypus was due to exacerbation of pre-existant infections acquired in their natural forest environment. Pneumocystis carinii is a well known cause of fatal, interstitial plasma-cell pneumonia in human infants and sometimes the weakened adult: the keeping of exotic pets such as the coatimundi is, therefore, not without some hazard in this respect. Histoplasma, another well known pathogen for man, was isolated from 4 rodents, Proechimys guyanensis (Echimyidae), all from virgin forest along the newly opened Trans Amazon Highway, Pará State, and from a single sloth, Choloepus didactylus, from near Belém, Pará. All these animals showed no symptoms of infection: isolation of the parasite was made by the inoculation of laboratory hamsters with saline suspensions of triturated liver and spleen.

  20. Rodents for comparative aging studies: from mice to beavers.

    Science.gov (United States)

    Gorbunova, Vera; Bozzella, Michael J; Seluanov, Andrei

    2008-09-01

    After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents.

  1. El Aragoniense Medio y Superior en el Suroeste de Madrid: Los nuevos yacimientos de Micromamíferos del Mioceno Medio de Villaviciosa de Odón y Leganés

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    Sesé, C.

    2014-06-01

    Full Text Available This paper discloses two new sites in the southwestern area of Madrid, Villaviciosa de Odón and Leganés, which have provided two rich micromammals associations of different ages. The micromammal association of the Villaviciosa de Odón site determined in this work is composed by the following taxa: Lagomorpha: Lagopsis peñai; Erinaceomorpha: Galerix cf. exilis; Soricomorpha: Miosorex cf. grivensis; Rodentia: Atlantoxerus sp., Microdyromys sp., Armantomys tricristatus, Megacricetodon collongensis and Democricetodon sp. This association, mainly by the evolutionary stage of Megacricetodon collongensis, corresponds to the E local biozone after Daams & Freudenthal (1988a from the end of the Middle Aragonian which is correlated with the end of the MN 5 Unit of Mein (1975. The micromammal association of the Leganés site consists of the following taxa: Lagomorpha: Lagopsis verus; Erinaceomorpha: Galerix cf. exilis; Rodentia: Heteroxerus cf. rubricati, Armantomys sp., Megacricetodon collongensis-crusafonti and cf. Democricetodon sp. Mainly by the evolutionary stage of Megacricetodon collongensis-crusafonti this association corresponds to the G1 local biozone after Daams et al. (1999 a y b which is correlated with the MN 6 Unit of Mein (1975. It is the only site known in Madrid of this age. Both micromammals associations suggest an open environment dominated by hard vegetation of steppe kind, and a dry and relatively warm climate.En este trabajo se dan a conocer dos nuevos yacimientos de la zona suroeste de Madrid, Villaviciosa de Odón y Leganés, que han proporcionado dos ricas asociaciones de micromamíferos de edades diferentes. La asociación de micromamíferos del yacimiento de Villaviciosa de Odón determinada en este trabajo está compuesta por los siguientes taxones: Lagomorpha: Lagopsis peñai; Erinaceomorpha: Galerix cf. exilis; Soricomorpha: Miosorex cf. grivensis; Rodentia: Atlantoxerus sp., Microdyromys sp., Armantomys tricristatus

  2. La fauna a micromammiferi del comprensorio di Muro Lucano (Potenza, Italia

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    Giuseppina Cerone

    1994-05-01

    Full Text Available Abstract Small mammal fauna of the Muro Lucano area (Potenza, Italy - Data of small mammals trapped (255 specimens and preyed by Barn owl (289 specimens in NW Lucania (southern Italy are reported. In the studied area, 7 species of Insectivora (Erinaceus europaeus, Talpa romana, Sorex araneus ve1 samniticus, S. minutus, Suncus etruscus, Crocidura suaveolens, C. leucodon and 8 of Rodentia (Muscardinus avellanarius, Myoxus glis, Clethrionomys glareolus, Microtus savii, Rattus rattus, Apodemus sylvaticus, A . flavicollis, Mus domesticus are recorded, together with ecological and biological remarks.

  3. Complete mitochondrial genome sequence of the Chinese scrub vole (Neodon irene).

    Science.gov (United States)

    Fan, Longqing; Fan, Zhenxin; Yue, Hao; Zhang, Xiuyue; Liu, Yang; Sun, Zhiyu; Liu, Shaoying; Yue, Bisong

    2011-06-01

    The Chinese scrub vole (Neodon irene) belongs to the subfamily Arvicolinae, which is restricted to mountain areas at high altitudes (2800-4000). In this study, we sequenced the complete mitochondrial genome of N. irene. It was determined to be 16,367 bases. The nucleotide sequence data of 12 heavy-strand protein-coding genes of N. irene and other 22 rodents were used for phylogenetic analysis. Bayesian inference (BI) and maximum likelihood (ML) were used. Both the BI and ML trees demonstrated that Microtus rossiaemeridionalis and Microtus kikuchii did not cluster together with each other. On the contrary, M. rossiaemeridionalis showed close relationship with N. irene. In the present study, only one sequence from Neodon and two sequences from Microtus were included in the phylogenetic analysis which should contribute to the unusual relationship. Therefore, in order to better understand the phylogenetic relationship within Rodentia, more rodents' complete mitochondrial genomes are required.

  4. Trois espèces nouvelles du genre Medwayella Traub, 1972 (Insecta : Siphonaptera : Pygiopsyllidae de Sabah (Malaisie Orientale, Île de Bornéo

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    Beaucournu J.C.

    2004-12-01

    Full Text Available Medwayella traubiana n. sp., M. pfeifferi n. sp. et M. sabahae n. sp. (Pygiopsyllidae sont décrites de Sabah (nord de l'île de Bornéo; les deux premières sur Tupaia tana (Scandentia, la troisième sur Sundasciurus lowii (Rodentia. Seuls les mâles peuvent être séparés, ces puces ayant été récoltées en sympatrie, voire en syntopie. Leur détermination est basée sur le segment IX et l'aedeagus ; si les deux premières sont affiliées à des espèces déjà connues, M. sabahae est nettement séparée des autres Medwayella

  5. El yacimiento plioceno del Pozo de Piedrabuena (Campo de Calatrava, provincia de Ciudad Real. geología, paleontología y análisis paleoambiental

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    Mazo, A. V.

    1991-12-01

    Full Text Available This paper deals with a sedimentological palaeontological and paleontological analysis of the Piedrabuena Water Well paleontological site (Ciudad Real, Campo de Calatrava, Castilla-La Mancha, Spain. The fossil mammal remains were accumulated by means of a low efficiency transport fan system, with mass transport mechanisms, which filled the whole of the Piedrabuena Depression: a circular shaped basin sorrounded by Paleozoic rocks (quartzites and shales. Neogene sedimentation evolved towards expansive palustrine carbonate sediments towards the top of the unit. The faunal assemblage composed of Rodentia indet., cf. Oryctolagus sp., Felis cf. issiodorensis, Hyaena sp., Dicerorhinus cf. etruscus, Sus minor, Cervidae indet (big sized, Cervidae Indet. (small sized, Gazella borbonica> and Hippotraginae indet. This fauna is characteristic of the Ruscinian-Villafranchian transition.En este trabajo se analizan las características geológicas y paleontológicas del yacimiento del Pozo de Piedrabuena, Ciudad Real (Castilla-La Mancha, España. Este yacimiento se localiza en materiales transportados por abanicos aluviales de pequeño desarrollo, que colmatan la Depresión de Piedrabuena, rodeada por rocas paleozoicas (cuarcitas y pizarras. A techo de los depósitos hay una expansión de carbonatos palustres. La fauna encontrada ha sido la siguiente: Rodentia indet., cf. Oryctolagus sp., Felix cf. issiodorensis, Hyaena sp., Dicerorhinus cf. etruscus, Cervidae indet. (talla grande, Cervidae indet. (talla pequeña, Gazella borbonica, Hippotraginae indet., que permite situar el yacimiento en el tránsito Rusciniense-Villafranquiense. El análisis paleoambiental muestra la coexistencia de especies de bosque y de zonas abiertas, lo que coincide bien con la estratificación de la vegetación de la zona: rala en las áreas centrales palustres y mucho más desarrollada sobre los abanicos aluviales áridos de los bordes.

  6. The role of wild mammals in the maintenance of Rift Valley fever virus.

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    Olive, Marie-Marie; Goodman, Steven M; Reynes, Jean-Marc

    2012-04-01

    Rift Valley fever virus (RVFV) is a zoonotic arbovirus affecting primarily domestic ruminants and humans. Numerous vector species are known or implicated in the transmission of RVFV. The role of mammals in the maintenance of RVFV, and the existence of a wild mammal reservoir in the epidemiologic cycle of RVFV, remain largely unknown. Our objective is to present a detailed review of studies undertaken on RVFV, often associated with wild mammals, with the aim of focusing future research on potential reservoirs of the virus. Natural and experimental infections related to RVFV in several mammalian orders, including Artiodactyla, Chiroptera, Rodentia, Primata (nonhuman), Perissodactyla, Carnivora, Proboscidea, Erinaceomorpha, and Lagomorpha, are reviewed; the first four orders have received the greatest attention. The possible role of wild ruminants, especially African buffalo (Syncerus caffer), is also discussed. Conflicting results have been published concerning rodents but, based on the literature, the likely candidate species include the African genera Arvicanthis and Micaelamys and the widely introduced roof rat (Rattus rattus). Members of the orders Chiroptera and Rodentia should receive greater attention associated with new research programs. For the other orders mentioned above, few data are available. We are unaware of any investigation concerning the orders Afrosoricida and Soricomorpha, which are represented in the geographic area of RVFV and can be abundant. As a first step to resolve the question of wild mammals as a reservoir of RVFV, serologic and virologic surveys should be promoted during epizootic periods to document infected wild animals and, in the case of positive results, extended to interepidemic periods to explore the role of wild animals as possible reservoirs.

  7. A Checklist of the Mammals of small Italian islands

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    Francesco Angelici

    2009-11-01

    Full Text Available Abstract Present knowledge on mammals of small Italian islands consists mainly of episodic records. In this paper we collect all available information about the distribution of wild mammals on 47 small Italian islands. A total of 37-38 species was found, including: 1 Erinaceomorpha, 4 Soricomorpha, 16-17 Chiroptera, 3 Lagomorpha, 7 Rodentia, 2 Carnivora and 4 Artiodactyla. The subspecific level has been identified whenever possible. The mammal fauna of the Isle of Elba (Tuscan Archipelago is the richest, with 24 species, while the most common species are Rattus rattus present on 47 islands Oryctolagus cuniculus (34, and Mus musculus (33. With the exception of Crocidura sicula, the current mammal fauna on small Italian islands originated from introductions.
    Riassunto Checklist dei mammiferi delle piccole isole italiane Lo stato attuale delle conoscenze sui mammiferi delle piccole isole del territorio italiano è frutto, perlopiù, di segnalazioni episodiche. Abbiamo raccolto le informazioni disponibili riguardo i mammiferi selvatici. Sono state prese in esame 47 isole, sulle quali è stata segnalata la presenza di un totale di 37-38 specie così ripartite: 1 Erinaceomorpha, 4 Soricomorpha, 16-17 Chiroptera, 3 Lagomorpha, 7 Rodentia, 2 Carnivora e 4 Artiodactyla. Quando possibile è stato identificato anche il livello subspecifico. In base ai dati finora disponibili, la teriofauna dell’Isola d’Elba (Arcipelago Toscano risulta quella più diversificata (24 specie, mentre le specie più diffuse sono Rattus rattus, presente su 47 isole, Oryctolagus cuniculus (34 e Mus musculus (33. Con l’eccezione di Crocidura sicula, i popolamenti attuali di mammiferi selvatici nelle piccole isole italiane sono originati da introduzioni operate dall’uomo.

  8. Small terrestrial mammals of Albania: annotated list and distribution

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    Ferdinand Bego

    2009-02-01

    Full Text Available Abstract: Abstract We report for Albania new records of small terrestrial mammals (Erinaceomorpha, Soricomorpha, Rodentia and outline previously published data. Twenty-four species (one hedgehog, six soricomorhps and 17 rodents have been collected in 161 localities surveyed throughout the country. Nine species (Neomys anomalus, Crocidura leucodon, Talpa stankovici, Dryomys nitedula, Muscardinus avellanarius, Micromys minutus, Mus macedonicus, Myodes glareolus, and Microtus thomasi are recorded for Albania for the first time. The present list is far from being complete and presence of a further 11 species has to be confirmed. Riassunto I Micromammiferi dell'Albania: status e distribuzione Viene presentato un quadro della distribuzione dei micromammiferi in Albania, evidenziando le specie di recente scoperta così come alcuni dati già pubblicati. L'esame di 161 località distribuite sull'intero territorio nazionale ha permesso di raccogliere informazioni sulla presenza di 24 specie di micromammiferi (1 Erinaceomorpha, 6 Soricomorpha e 17 Rodentia. Nove specie  (Neomys anomalus, Crocidura leucodon, Talpa stankovici, Dryomys nitedula, Muscardinus avellanarius, Micromys minutus, Mus macedonicus, Myodes glareolus, e Microtus thomasi vengono segnalate per la prima volta. L'elenco qui presentato non può essere considerato definitivo. Ulteriori ricerche potrebbero accertare la presenza di altre 11 specie.

  9. Schistosoma mansoni Sambon, 1907: comparative morphologica studies of some Brazilian strains Schistosoma mansoni Sambon, 1907: estudos comparativos da morfologia de algumas cepas brasileiras

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    José Roberto Machado-Silva

    1995-10-01

    Full Text Available The morphology of Schistosoma mansoni adult male worms from three strains which have been maintained in albino mice for several generations, was compared to a strain that has been isolated from the natural host Nectomys squamipes (Rodentia: Muridae captured in Sumidouro (Rio de Janeiro State and have been maintained in the same sylvatic rodent under laboratory conditions. Total length of specimens, distance between suckers, the number of testes and extention of testes grouping were the taxonomic characters analysed. The worms recovered from N. squamipes showed expressive differences (pA morfologia de vermes adultos machos de tres cepas de Schistosoma mansoni, mantidas por várias gerações em camundongos albinos, foi comparada com uma cepa isolada do hospedeiro natural Nectomys squamipes (Rodentia: Muridae e mantida, em laboratório, neste mesmo roedor silvestre. Como caracteres taxonômicos foram analisados o comprimento total, o numero de testículos, a distância entre as ventosas e a distância ocupada pelos testículos nos espécimes. Os vermes recuperados de N. squamipes apresentaram diferenças significativas (p<0,01 em relação às outras cepas para quaisquer caracteres morfológicos estudados. As cepas mantidas em camundongos apresentaram diferença estatística em vários caracteres (p<0,01. Alguns vermes adultos além da disposição normal dos testículos, apresentavam também uma localização atípica destas glândulas sexuais. Conclui-se que a morfologia dos vermes adultos pode ser utilizada para caracterizar cepas de S. mansoni e que as passagens sucessivas de uma cepa em camundongos não induzem a alterações morfológicas nos vermes adultos.

  10. Flying lemurs – The 'flying tree shrews'? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade

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    Volobouev Vitaly

    2008-05-01

    Full Text Available Abstract Background Flying lemurs or Colugos (order Dermoptera represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires, the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous. Results To search for cytogenetic signatures that could help to clarify the evolutionary affinities within this superordinal group, we have established a genome-wide comparative map between human and the Malayan flying lemur (Galeopterus variegatus by reciprocal chromosome painting using both human and G. variegatus chromosome-specific probes. The 22 human autosomal paints and the X chromosome paint defined 44 homologous segments in the G. variegatus genome. A putative inversion on GVA 11 was revealed by the hybridization patterns of human chromosome probes 16 and 19. Fifteen associations of human chromosome segments (HSA were detected in the G. variegatus genome: HSA1/3, 1/10, 2/21, 3/21, 4/8, 4/18, 7/15, 7/16, 7/19, 10/16, 12/22 (twice, 14/15, 16/19 (twice. Reverse painting of G. variegatus chromosome-specific paints onto human chromosomes confirmed the above results, and defined the origin of the homologous human chromosomal segments in these associations. In total, G. variegatus paints revealed 49 homologous chromosomal segments in the HSA genome. Conclusion Comparative analysis of our map with published maps from representative species of other placental orders, including Scandentia, Primates, Lagomorpha and Rodentia, suggests a signature rearrangement (HSA2q/21 association that links Scandentia and Dermoptera to one sister clade. Our results thus provide new evidence for the hypothesis that Scandentia and Dermoptera have a closer phylogenetic relationship to each other than either of them has to Primates.

  11. The hip adductor muscle group in caviomorph rodents: anatomy and homology.

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    García-Esponda, César M; Candela, Adriana M

    2015-06-01

    Anatomical comparative studies including myological data of caviomorph rodents are relatively scarce, leading to a lack of use of muscular features in cladistic and morphofunctional analyses. In rodents, the hip adductor muscles constitute an important group of the hindlimb musculature, having an important function during the beginning of the stance phase. These muscles are subdivided in several distinct ways in the different clades of rodents, making the identification of their homologies hard to establish. In this contribution we provide a detailed description of the anatomical variation of the hip adductor muscle group of different genera of caviomorph rodents and identify the homologies of these muscles in the context of Rodentia. On this basis, we identify the characteristic pattern of the hip adductor muscles in Caviomorpha. Our results indicate that caviomorphs present a singular pattern of the hip adductor musculature that distinguishes them from other groups of rodents. They are characterized by having a single m. adductor brevis that includes solely its genicular part. This muscle, together with the m. gracilis, composes a muscular sheet that is medial to all other muscles of the hip adductor group. Both muscles probably have a synergistic action during locomotion, where the m. adductor brevis reinforces the multiple functions of the m. gracilis in caviomorphs. Mapping of analyzed myological characters in the context of Rodentia indicates that several features are recovered as potential synapomorphies of caviomorphs. Thus, analysis of the myological data described here adds to the current knowledge of caviomorph rodents from anatomical and functional points of view, indicating that this group has features that clearly differentiate them from other rodents.

  12. Histopatologia da infecção por Yersinia pestis em roedores de focos de peste do Nordeste brasileiro Histopathology of Yersinia pestis infection in rodents from plague foci of Brazilian Northeast

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    Eridan M. Coutinho

    1982-06-01

    Full Text Available O presente trabalho mostra a histopatologia da infecção pela Yersinia pestis, entre as diferentes espécies de roedores silvestres e comensais (cricetídeos, equimídeos, murídeos e cavídeos que ocorrem na zona endêmica de peste do Nordeste do Brasil. Estes roedores foram encontrados naturalmente infectados nos campos ou inoculados experimentalmente no laboratório (vias percutânea, subcutânea ou picada de pulgas com cepas locais e/ou estrangeiras de Yersiniapestis. Quase todos os animais, exceto alguns dos cavídeos, desenvolveram a forma bubosepticêmica da peste. Entre as lesões encontradas, a necrose coagulativa multifocal do fígado, a pneumonite intersticial aguda difusa e a atrofia linfoide do baço, podem, por sua constância, ser consideradas como os principais indicadores histológicos da infecção pestosa, embora estas lesões não sejam exclusivas da peste. A diversidade e a intensidade das lesões entre os Zygodontomys lasiurus pixuna, podem explicar a mortalidade elevada desta espécie e a disseminação da peste nos focos naturais do Nordeste brasileiro. Cricetídeos e murídeos mostraram alterações histopatológicas qualitativamente semelhantes. A resistência dos cavídeos à infecção pestosa foi evidenciada pela sobrevida desses roedores à fase aguda da infecção e pelo desenvolvimento de uma reação histiocitária interna, delimitando as áreas abscedadas. è possível que estas lesões crônicas abriguem bacilos virulentos, que permitirão a reinfecção periódica das pulgas e conseqüente reativação do processo epizoótico.In this paper, the histopathological aspects of plague infection in different species of wild and domestic rodents (cricetidae, echymidae, muridae and cavidae are described. All of them had been trapped in endemic plague areas and harboured natural infection, while others were laboratory infected by different routes (percutaneous, subcutaneous rout, fleas bite. Several national and

  13. Seasonal and geographic variation of southern blue whale subspecies in the Indian Ocean.

    Science.gov (United States)

    Samaran, Flore; Stafford, Kathleen M; Branch, Trevor A; Gedamke, Jason; Royer, Jean-Yves; Dziak, Robert P; Guinet, Christophe

    2013-01-01

    Understanding the seasonal movements and distribution patterns of migratory species over ocean basin scales is vital for appropriate conservation and management measures. However, assessing populations over remote regions is challenging, particularly if they are rare. Blue whales (Balaenoptera musculus spp) are an endangered species found in the Southern and Indian Oceans. Here two recognized subspecies of blue whales and, based on passive acoustic monitoring, four "acoustic populations" occur. Three of these are pygmy blue whale (B.m. brevicauda) populations while the fourth is the Antarctic blue whale (B.m. intermedia). Past whaling catches have dramatically reduced their numbers but recent acoustic recordings show that these oceans are still important habitat for blue whales. Presently little is known about the seasonal movements and degree of overlap of these four populations, particularly in the central Indian Ocean. We examined the geographic and seasonal occurrence of different blue whale acoustic populations using one year of passive acoustic recording from three sites located at different latitudes in the Indian Ocean. The vocalizations of the different blue whale subspecies and acoustic populations were recorded seasonally in different regions. For some call types and locations, there was spatial and temporal overlap, particularly between Antarctic and different pygmy blue whale acoustic populations. Except on the southernmost hydrophone, all three pygmy blue whale acoustic populations were found at different sites or during different seasons, which further suggests that these populations are generally geographically distinct. This unusual blue whale diversity in sub-Antarctic and sub-tropical waters indicates the importance of the area for blue whales in these former whaling grounds.

  14. Repeated Reticulate Evolution in North American Papilio machaon Group Swallowtail Butterflies.

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    Julian R Dupuis

    Full Text Available Hybridization between distinct populations or species is increasingly recognized as an important process for generating biodiversity. However, the interaction between hybridization and speciation is complex, and the diverse evolutionary outcomes of hybridization are difficult to differentiate. Here we characterize potential hybridization in a species group of swallowtail butterflies using microsatellites, DNA sequences, and morphology, and assess whether adaptive introgression or homoploid hybrid speciation was the primary process leading to each putative hybrid lineage. Four geographically separated hybrid populations were identified in the Papilio machaon species group. One distinct mitochondrial DNA clade from P. machaon was fixed in three hybrid taxa (P. brevicauda, P. joanae, and P. m. kahli, while one hybrid swarm (P. zelicaon x machaon exhibited this hybrid mtDNA clade as well as widespread parental mtDNA haplotypes from both parental species. Microsatellite markers and morphology showed variable admixture and intermediacy, ranging from signatures of prolonged differential introgression from the paternal species (P. polyxenes/P. zelicaon to current gene flow with both parental species. Divergences of the hybrid lineages dated to early- to mid-Pleistocene, suggesting that repeated glaciations and subsequent range shifts of parental species, particularly P. machaon hudsonianus, facilitated initial hybridization. Although each lineage is distinct, P. joanae is the only taxon with sufficient evidence (ecological separation from parental species to define it as a homoploid hybrid species. The repetition of hybridization in this group provides a valuable foundation for future research on hybridization, and these results emphasize the potential for hybridization to drive speciation in diverse ways.

  15. Risk assessment of land-applied biosolids-borne triclocarban (TCC).

    Science.gov (United States)

    Snyder, Elizabeth Hodges; O'Connor, George A

    2013-01-01

    Triclocarban (TCC) is monitored under the USEPA High Production Volume (HPV) chemical program and is predominantly used as the active ingredient in select antibacterial bar soaps and other personal care products. The compound commonly occurs at parts-per-million concentrations in processed wastewater treatment residuals (i.e. biosolids), which are frequently land-applied as fertilizers and soil conditioners. Human and ecological risk assessment parameters measured by the authors in previous studies were integrated with existing data to perform a two-tiered human health and ecological risk assessment of land-applied biosolids-borne TCC. The 14 exposure pathways identified in the Part 503 Biosolids Rule were expanded, and conservative screening-level hazard quotients (HQ values) were first calculated to estimate risk to humans and a variety of terrestrial and aquatic organisms (Tier 1). The majority of biosolids-borne TCC exposure pathways resulted in no screening-level HQ values indicative of significant risks to exposed organisms (including humans), even under worst-case land application scenarios. The two pathways for which the conservative screening-level HQ values exceeded one (i.e. Pathway 10: biosolids➔soil➔soil organism➔predator, and Pathway 16: biosolids➔soil➔surface water➔aquatic organism) were then reexamined using modified parameters and scenarios (Tier 2). Adjusted HQ values remained greater than one for Exposure Pathway 10, with the exception of the final adjusted HQ values under a one-time 5 Mg ha(-1) (agronomic) biosolids loading rate scenario for the American woodcock (Scolopax minor) and short-tailed shrew (Blarina brevicauda). Results were used to prioritize recommendations for future biosolids-borne TCC research, which include additional measurements of toxicological effects and TCC concentrations in environmental matrices at the field level.

  16. Species Diversity in the Parasitoid Genus Asobara (Hymenoptera: Braconidae from the Native Area of the Fruit Fly Pest Drosophila suzukii (Diptera: Drosophilidae.

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    Emilio Guerrieri

    Full Text Available Drosophila suzukii (Matsumura, commonly known as Spotted Wing Drosophila (SWD, is a worldwide serious economic threat to the production of berries and stone fruits. The chemical control widely used against this pest is often not able to preventing yield losses because wild flora offers an abundance of fruits to D. suzukii where the pest is able to reproduce and from where it recolonizes neighbouring cultivated fields. Alternatively, within Integrated Pest Management protocols for D. suzukii, biological control could play a key role by reducing its populations particularly in non-cultivated habitats, thus increasing the effectiveness and reducing the side negative effects of other management strategies. Because of the scarcity and of the low efficiency of autochthonous parasitoids in the new invaded territories, in the last few years, a number of surveys started in the native area of D. suzukii to find parasitoid species to be evaluated in quarantine structures and eventually released in the field, following a classical biological control approach. This paper reports the results of these surveys carried out in South Korea and for the first time in China. Among the parasitoids collected, those belonging to the genus Asobara Foerster resulted dominant both by number and species diversity. By combining morphological characters and the mitochondrial COI gene as a molecular marker, we identified seven species of Asobara, of which two associated with D. suzukii, namely A. japonica and A leveri, and five new to science, namely Asobara brevicauda, A. elongata, A mesocauda, A unicolorata, A. triangulata. Our findings offer new opportunity to find effective parasitoids to be introduced in classical biological control programmes in the territories recently invaded by D. suzukii.

  17. Caracterización preliminar de las comunidades de murciélagos asociados a seis cavernas en Charalá y Ocamonte (Santander, Colombia

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    Rodríguez P. Miguel E.

    2005-12-01

    Full Text Available Las cavernas se constituyen como refugios empleados por algunas especies de murciélagos y como ecosistemas que albergan comunidades bióticas singulares. En este trabajo se describe la presencia y riqueza de especies de murciélagos asociados a cavernas. Con este fin, se realizó una salida de campo de siete días a seis cavernas ubicadas en los municipios de Charalá y Ocamonte (Santander, Colombia. Se estimó la riqueza de especies de murciélagos y otras variables como:
    ubicación respecto a la intensidad de luz, tipo de agrupación y tipo de refugio empleado. Igualmente, se determinaron variables físicas de las cuevas como longitud y ancho  promedio, número de entradas y complejidad interior. Se sugiere la existencia de relaciones entre las variables de la
    comunidad y las características físicas evaluadas en estas cavernas. Se registran seis especies de murciélagos pertenecientes a las familias Vespertilionidae y Phyllostomidae con un promedio de 2,2 especies por caverna. Algunas especies presentan preferencias por un tipo de refugio específico dentro de las cuevas. Las especies registradas fueron: Phyllostomus discolor, Anoura geoffroyi, Carollia
    brevicauda, Plathyrrhinus dorsalis, Desmodus rotundus y Myotis keaysi, dos de éstas se consideran nuevos registros de especies asociadas a los sistemas cársticos del país.

  18. The Community Structure and Vertical Distribution of Small Mammal in Baicaoling Mt., Yunnan Province,China%云南白草岭鼠形小兽群落结构及垂直分布

    Institute of Scientific and Technical Information of China (English)

    张云智; 龚正达; 冯锡光; 段兴德; 吴厚永; 翁学; 吕元

    2002-01-01

    对云南白草岭鼠形小兽群落结构、垂直分布及动物区系进行了调查.结果共捕获小兽21种1 028只,隶属于啮齿目(Rodenria)鼠科(Muridae)10种,仓鼠科(Cricetidae)2种,松鼠科(Sciuridae)2种;食虫目(Insectivora)NFDA3NFDA4科(Soricdae)6种,鼹科(Talpidae)1种.其中东洋界15种,占71.43%,古北界4种,占19.04%,广布种2种,占9.53%.各个垂直带鼠形小兽群落物种多样性指数分别为,Ⅰ .云南松林及山坡耕作地带(2 000~2 650 m)1.381 4;Ⅱ .温凉性针阔叶混交林带(2 650~3 150 m)1.612 6;Ⅲ.苍山冷杉林带(3 150~3 500 m)1.348 8;Ⅳ.亚高山灌丛草甸带(3 500~3 657 m)1.508 5.云南白草岭优势种主要由齐氏姬鼠(Apodemus chevieri)、中华姬鼠(A. draco)、大耳姬鼠(A. latronum)、大绒鼠(Eothenomys miletus)和昭通绒鼠(E.olitor)5种组成.

  19. Dieta de Leopardus colocolo (Carnivora: Felidae en la Reserva Nacional de Junín, Junín, Perú

    Directory of Open Access Journals (Sweden)

    Ursula Fajardo

    2014-05-01

    Full Text Available Este estudio caracteriza la dieta de Leopardus colocolo en los alrededores del lago Junín, en el centro del Perú, a partir de los restos de las presas presentes en 43 heces. El origen de las heces del predador se determinó a partir del ADN mitocondrial de las células epiteliales intestinales adheridas a la superficie de las heces, utilizando como marcador la región de control. Los restos de las presas fueron identificados utilizando literatura especializada y la comparación con especímenes de colección, identificando un total of 14 ítems alimenticios pertenecientes a mamíferos de las familias Cricetidae (6, Chinchillidae (1 y Caviidae (1 y aves de las familias Anatidae (3 y Rallidae (2, y un grupo de aves no identificadas (1. Los roedores fueron el principal componente de la dieta de L. colocolo, en frecuencia y biomasa, seguido por las aves. Entre los ítems alimenticios consumidos, el roedor cricétido pequeño Calomys sp. fue el más frecuente; sin embargo, el mayor aporte de biomasa relativa fue proporcionado por el roedor mediano Cavia tschudii. La amplitud de nicho obtenida fue baja (Bsta= 0.17, indicando una dieta especializada. Nuestros resultados confirman que, como ocurre con la mayoría de felinos pequeños neotropicales, L. colocolo es un predador especializado en la captura de vertebrados, principalmente mamíferos pequeños. No se registró variación estacional en la dieta y el análisis de las clases de edad de los roedores cricétidos mostró que los adultos fueron los más consumidos. Se infiere que L. colocolo tiene un patrón de actividad diurno y nocturno.

  20. Hosts, distribution and genetic divergence (16S rDNA) of Amblyomma dubitatum (Acari: Ixodidae).

    Science.gov (United States)

    Nava, Santiago; Venzal, José M; Labruna, Marcelo B; Mastropaolo, Mariano; González, Enrique M; Mangold, Atilio J; Guglielmone, Alberto A

    2010-08-01

    We supply information about hosts and distribution of Amblyomma dubitatum. In addition, we carry out an analysis of genetic divergence among specimens of A. dubitatum from different localities and with respect to other Neotropical Amblyomma species, using sequences of 16S rDNA gene. Although specimens of A. dubitatum were collected on several mammal species as cattle horse, Tapirus terrestris, Mazama gouazoubira, Tayassu pecari, Sus scrofa, Cerdocyon thous, Myocastor coypus, Allouata caraya, Glossophaga soricina and man, most records of immature and adult stages of A. dubitatum were made on Hydrochoerus hydrochaeris, making this rodent the principal host for all parasitic stages of this ticks. Cricetidae rodents (Lundomys molitor, Scapteromys tumidus), opossums (Didelphis albiventris) and vizcacha (Lagostomus maximus) also were recorded as hosts for immature stages. All findings of A. dubitatum correspond to localities of Argentina, Brazil, Paraguay and Uruguay, and they were concentrated in the Biogeographical provinces of Pampa, Chaco, Cerrado, Brazilian Atlantic Forest, Parana Forest and Araucaria angustifolia Forest. The distribution of A. dubitatum is narrower than that of its principal host, therefore environmental variables rather than hosts determine the distributional ranges of this tick. The intraspecific genetic divergence among 16S rDNA sequences of A. dubitatum ticks collected in different localities from Argentina, Brazil and Uruguay was in all cases lower than 0.8%, whereas the differences with the remaining Amblyomma species included in the analysis were always bigger than 6.8%. Thus, the taxonomic status of A. dubitatum along its distribution appears to be certain at the specific level.

  1. Infecção natural do rato, Oryzomys nigripes (Desmarest. 1819 pelo T. cruzi

    Directory of Open Access Journals (Sweden)

    Rosa Domingues Ribeiro

    1972-02-01

    Full Text Available Os autores, após uma revisão dos achados de roedores da família Cricetidae e do gênero Oryzomys infectados pelo T. cruzi, assinalam a infecção de um exemplar do rato, Oryzomys nigripes (Desmarest, 1819, capturado no Bairro da Ilha, município de Salto de Pirapora, Estado de São Paulo, Brasil, e cuja amostra de T. cruzi foi isolada através do xenodiagnóstico. O tripanossomo em estudo mostrou-se patogênico para ratos Wistar e camundongos brancos jovens, infectando 100,0% dos animais inoculados. As formas sanguícolas nos camundongos têm 24,25μ. de comprimento total médio e 1,27μ, de índice nuclear médio. Nos animais sacrificados durante a fase aguda da infecção ninhos de leishmânias foram observados, em fibras cardíacas. A infecção experimental de camundongos inoculados com sangue parasitado é leve, com período prepatente relativamente longo (média de 7,1 dias, com baixa parasitemia, e duração da fase aguda variando de 55 a 64 dias. Provas de proteção mostraram que a amostra em estudo confere aos camundongos que sobreviveram alto grau de resistência contra reinfecções pela amostra Y. O tripanossomo cultiva-se bem em meio de Mac Neal - Novy e em meio líquido de Warren. Infecta regularmente triatomíneos, dando os seguintes índices de infecção: P. megistus - 100,0%, T. infestans - 76,7%, T. sórdida - 86,7%o e R. neglectus - 100,0%.

  2. Sexual selection and the adaptive evolution of PKDREJ protein in primates and rodents.

    Science.gov (United States)

    Vicens, Alberto; Gómez Montoto, Laura; Couso-Ferrer, Francisco; Sutton, Keith A; Roldan, Eduardo R S

    2015-02-01

    PKDREJ is a testis-specific protein thought to be located on the sperm surface. Functional studies in the mouse revealed that loss of PKDREJ has effects on sperm transport and the ability to undergo an induced acrosome reaction. Thus, PKDREJ has been considered a potential target of post-copulatory sexual selection in the form of sperm competition. Proteins involved in reproductive processes often show accelerated evolution. In many cases, this rapid divergence is promoted by positive selection which may be driven, at least in part, by post-copulatory sexual selection. We analysed the evolution of the PKDREJ protein in primates and rodents and assessed whether PKDREJ divergence is associated with testes mass relative to body mass, which is a reliable proxy of sperm competition levels. Evidence of an association between the evolutionary rate of the PKDREJ gene and testes mass relative to body mass was not found in primates. Among rodents, evidence of positive selection was detected in the Pkdrej gene in the family Cricetidae but not in Muridae. We then assessed whether Pkdrej divergence is associated with episodes of sperm competition in these families. We detected a positive significant correlation between the evolutionary rates of Pkdrej and testes mass relative to body mass in cricetids. These findings constitute the first evidence of post-copulatory sexual selection influencing the evolution of a protein that participates in the mechanisms regulating sperm transport and the acrosome reaction, strongly suggesting that positive selection may act on these fertilization steps, leading to advantages in situations of sperm competition.

  3. ROEDORES PEQUEÑOS EN UN SISTEMA DE PRODUCCIÓN DE GANADO LECHERO

    Directory of Open Access Journals (Sweden)

    Rodolfo WingChing-Jones

    2009-01-01

    Full Text Available Con el objetivo de identificar las especies de roedores pequeños asocia das a un sistema de producción de ganado de leche ubicado en Turria lba, Ca rtago, Costa Ri ca, se muestreó durante los meses de mayo del 2007 a abril del 2008 un área de potrero con cobertura permanente de pasto estrella africana (Cynodon nlemfuensis, una área de instalaciones y un bosque secundario de 15 años. Los muestreos fueron mensuales durante dos períodos consecutivos de 24 horas, se utilizaron trampas de golpe Victor®, instaladas entre las 7:00 y 8:00 horas, con observaciones a la misma hora, durante los dos días siguie ntes. Se utilizó como cebo atrayente, una mezcla de avena, alimento balanceado y banano maduro, en proporciones similares. En el hábitat de potrero se usaron 30 trampas distancia das entre sí por 10 m, en las instalaciones se colocaron 14 estaciones de muestreo distribuidas en área de cuido de terneras (4, bodega de alimento (3, bodega de herramie ntas (3 y área de producción de abono orgánico (4. En el bosque se utilizaron 10 trampas en un arreglo de 10 x 5 m entre trampa (largo x ancho. Se capturaron tres especie s de roedores pequeños, un ejemplar de Liomys salvini (Heteromyidae en el bosque, ocho ejemplares de Melanomys caliginosus (Cricetidae en área de potrero y de bosque y ocho ejemplares de Rattus rattus (Muridae en área de instalaciones.

  4. CACERÍA DE SUBSISTENCIA DE MAMÍFEROS EN EL SECTOR ORIENTAL DE LA RESERVA DE BIÓSFERA EL TUPARRO – VICHADA

    Directory of Open Access Journals (Sweden)

    Mónica del Pilar Martínez Salas

    2015-11-01

    Full Text Available RESUMENLa cacería de subsistencia ha sido una actividad de vital importancia para las comunidades indígenas como fuente de proteína y venta. Se caracterizó la cacería de subsistencia realizada por comunidades de las etnias Piaroa y Curripaco presentes en la Reserva de Biosfera el Tuparro, por medio de registros de caza durante nueve meses de estudio. Se encontró que no hay diferencias significativas en cuanto a especies y número de individuos cazados entre las dos etnias, siendo Artiodactyla y Rodentia los órdenes con mayor aporte respecto al número de individuos, biomasa y riqueza de especies, lo cual fue similar a otros estudios realizados en el Neotrópico. Los Piaroa cazan más frecuentemente cuando los estudiantes llegan de la ciudad al resguardo, mientras que los Curripaco lo hacen para las reuniones evangélicas. El arte de caza más usado por las comunidades de las dos etnias fue la escopeta. Las etnias estudiadas tienen sus zonas de caza en la Reserva de Biósfera El Tuparro, y en ellas, los Curripaco están aprovechando directamente los recursos de su zona núcleo del Parque Nacional Natural El Tuparro.ABSTRACTSubsistence hunting has been an activity of vital importance to indigenous communities as a source of protein and sale. We characterized subsistence hunting by Curripaco and Piaroa ethnic groups present in the Tuparro Biosphere Reserve, through hunting records over nine months of study. We found no significant differences in species and number of individuals hunted by the two ethnic groups. The orders Rodentia and Artiodactyla contributed the most in terms of number of individuals, biomass and species richness, which was similar to studies to the Neotropics. The Piaroa hunt more frequently when students return to the community lands from the city, while the Curripaco do so for religious gatherings. The hunting method used most often by both ethnic groups was the shotgun. The hunting areas used by ethnic groups are within

  5. Relaciones biogeográficas de los sistemas montañosos de la Península Ibérica: el caso de los micromamíferos

    Directory of Open Access Journals (Sweden)

    Vargas, J. M.

    2003-12-01

    Full Text Available In the present paper we analyse the biogeographical relationship between the 12 mountain ranges surrounding the western Mediterranean basin, according to their micromammal fauna (70 species belonging to the orders Erinaceomorpha, Soricomorpha and Rodentia. Using an area classification analysis, we performed a biogeographical regionalization of the study area, and later we characterised the biotic boundaries detected. We also identified the interchanges of species that could have happened between the mountain ranges considered. A strong boundary exists between the European and African faunas, which is characterised by a higher energy availability in the south. For non-rodents micromammals there is also a week boundary between the exclusively-Iberian mountain ranges and the northern ones, which is characterised by a higher simultaneous availability of water and energy in the north. Finally, we suggest the existence of a main interchange of species between Europe and the Iberian Peninsula.

    En el presente artículo se analiza la relación biogeográfica de los 12 sistemas montañosos que circundan la parte más occidental de la cuenca mediterránea, en función de su fauna de micromamíferos (70 especies pertenecientes a los órdenes Erinaceomorpha, Soricomorpha y Rodentia. Se ha llevado a cabo una regionalización biogeográfica del área de estudio, mediante un análisis de clasificación de áreas, y posteriormente se han caracterizado ambientalmente las fronteras bióticas detectadas. Por último, se han identificado los posibles intercambios de especies que han tenido lugar entre los sistemas montañosos considerados. Existe una frontera fuerte entre las faunas europea y africana, caracterizada en términos ambientales por una mayor disponibilidad de energía en el sur. Además, para los micromamíferos no roedores, se detecta una frontera débil que separa los sistemas montañosos exclusivamente ibéricos del resto, caracterizada por

  6. An explanation of the relationship between mass, metabolic rate and characteristic length for placental mammals

    Directory of Open Access Journals (Sweden)

    Charles C. Frasier

    2015-09-01

    Full Text Available The Mass, Metabolism and Length Explanation (MMLE was advanced in 1984 to explain the relationship between metabolic rate and body mass for birds and mammals. This paper reports on a modernized version of MMLE. MMLE deterministically computes the absolute value of Basal Metabolic Rate (BMR and body mass for individual animals. MMLE is thus distinct from other examinations of these topics that use species-averaged data to estimate the parameters in a statistically best fit power law relationship such as BMR = a(bodymassb. Beginning with the proposition that BMR is proportional to the number of mitochondria in an animal, two primary equations are derived that compute BMR and body mass as functions of an individual animal’s characteristic length and sturdiness factor. The characteristic length is a measureable skeletal length associated with an animal’s means of propulsion. The sturdiness factor expresses how sturdy or gracile an animal is. Eight other parameters occur in the equations that vary little among animals in the same phylogenetic group. The present paper modernizes MMLE by explicitly treating Froude and Strouhal dynamic similarity of mammals’ skeletal musculature, revising the treatment of BMR and using new data to estimate numerical values for the parameters that occur in the equations. A mass and length data set with 575 entries from the orders Rodentia, Chiroptera, Artiodactyla, Carnivora, Perissodactyla and Proboscidea is used. A BMR and mass data set with 436 entries from the orders Rodentia, Chiroptera, Artiodactyla and Carnivora is also used. With the estimated parameter values MMLE can calculate characteristic length and sturdiness factor values so that every BMR and mass datum from the BMR and mass data set can be computed exactly. Furthermore MMLE can calculate characteristic length and sturdiness factor values so that every body mass and length datum from the mass and length data set can be computed exactly. Whether or

  7. Parasitic helminths of small mammals in Elba Island

    Directory of Open Access Journals (Sweden)

    Alexis Ribas

    2003-10-01

    Full Text Available We investigated the helminth fauna of small mammals (Rodentia and Insectivora in the mediterranean island of Elba (Italy. We first performed a survey of the parasitic helminths of Rattus rattus (L., 1758, Mus domesticus (Schwarz & Schwarz, 1943 (Rodentia, Murinae, Crocidura suaveolens (Pallas, 1811 (Insectivora, Soricidae and Erinaceus europaeus L., 1758 (Insectivora, Erinaceidae. An expedition was undertaken in January 2002 making an helminth faunistic study of: 14 R. rattus; 11 M. domesticus; 2 C. suaveolens and 1 E. europaeus. A total of 28 animals were trapped at seven stations and nine helminth species were detected: Corrigia vitta Dujardin, 1845 (Dicrocoelidae, Brachylaima erinacei Blanchard, 1847 (Brachylaimidae [Digenea]; Hymenolepis diminuta (Rudolphi, 1819; H. tiara (Dujardin, 1845 (Cestoda, Hymenolepididae; Aonchotheca erinacei Rudolphi, 1819; Capillaria hepatica Bancroft, 1893 (Trichuridae; Mastophorus muris (Gmelin, 1790 (Spirocercidae; Paracrenosoma kontrimavinchusi Guenov, 1978 (Metastrongylidae; Syphacia muris (Yamaguti, 1935 (Oxyuridae [Nematoda]. The house mice were not infected by helminths. In the black rat, five species were detected: C. vitta, H. diminuta, C. hepaticum, M. muris and S. muris. Insectivores hosts were parasitised by B. erinacei, A. erinacei (E. europaeus, H. tiara and P. kontrimavinchusi (C. suaveolens. All species were identified by morphological characteristics and in the cases of H. diminuta and M. muris isozyme electrophoresis were used to compare with continental and insular samples. Helminths found in these hosts in Elba Island (apart of P. kontrimavinchusi are the best colonisers of mediterranean islands. These species were

  8. An explanation of the relationship between mass, metabolic rate and characteristic length for placental mammals

    Science.gov (United States)

    2015-01-01

    The Mass, Metabolism and Length Explanation (MMLE) was advanced in 1984 to explain the relationship between metabolic rate and body mass for birds and mammals. This paper reports on a modernized version of MMLE. MMLE deterministically computes the absolute value of Basal Metabolic Rate (BMR) and body mass for individual animals. MMLE is thus distinct from other examinations of these topics that use species-averaged data to estimate the parameters in a statistically best fit power law relationship such as BMR = a(bodymass)b. Beginning with the proposition that BMR is proportional to the number of mitochondria in an animal, two primary equations are derived that compute BMR and body mass as functions of an individual animal’s characteristic length and sturdiness factor. The characteristic length is a measureable skeletal length associated with an animal’s means of propulsion. The sturdiness factor expresses how sturdy or gracile an animal is. Eight other parameters occur in the equations that vary little among animals in the same phylogenetic group. The present paper modernizes MMLE by explicitly treating Froude and Strouhal dynamic similarity of mammals’ skeletal musculature, revising the treatment of BMR and using new data to estimate numerical values for the parameters that occur in the equations. A mass and length data set with 575 entries from the orders Rodentia, Chiroptera, Artiodactyla, Carnivora, Perissodactyla and Proboscidea is used. A BMR and mass data set with 436 entries from the orders Rodentia, Chiroptera, Artiodactyla and Carnivora is also used. With the estimated parameter values MMLE can calculate characteristic length and sturdiness factor values so that every BMR and mass datum from the BMR and mass data set can be computed exactly. Furthermore MMLE can calculate characteristic length and sturdiness factor values so that every body mass and length datum from the mass and length data set can be computed exactly. Whether or not MMLE can

  9. The ecology of the Trypanosoma cruzi transmission cycle: Dispersion of zymodeme 3 (Z3) in wild hosts from Brazilian biomes.

    Science.gov (United States)

    Lisboa, Cristiane Varella; Xavier, Samanta Cristina das Chagas; Herrera, Heitor Miraglia; Jansen, Ana Maria

    2009-10-28

    Two main genotypes in Trypanosoma cruzi subpopulations can be distinguished by PCR amplification of sequences from the mini-exon gene non-transcribed spacer, respectively, T. cruzi I (TCI) and T. cruzi II (TCII). This technique is also capable of distinguishing a third assemblage of subpopulations that do not fit in these genotypes and that remain known as zymodeme Z3 (Z3). The distribution pattern as well as the mammalian host range of this latter T. cruzi sublineage still remains unclear. Thus, the intention of our study was to increase the information regarding these aspects. The mini-exon analysis of T. cruzi isolates obtained from sylvatic animals in the Amazon Forest, Atlantic Rainforest, Caatinga and Pantanal showed that prevalence of the Z3 subpopulation in nature was low (15 out of 225 isolates, corresponding to 7%). A higher prevalence of Z3 was observed in the Caatinga (15%) and the Pantanal (12%). Infection by Z3 was observed in mammalian hosts included in Carnivora, Chiroptera, Didelphimorphia, Rodentia and Xernathra. The T. cruzi Z3 subpopulation was observed also in mixed infections (33%) with TCI (n=2) and TCII (n=3). These results demonstrate that T. cruzi Z3 displays a wider distribution and host range than formerly understood as it has been demonstrated to be able infect species included in five orders of mammalian host species dispersed through all forest strata of the four Brazilian biomes evaluated.

  10. SPECIES DIVERSITY AND COMMUNITY STRUCTURE OF SUCKING LICE IN YUNNAN, CHINA

    Institute of Scientific and Technical Information of China (English)

    Xian-guoGuo; Ti-junQian; Li-junGuo; JingWang; Wen-geDong; LiZhang; Zhi-minMa; andWeiLi

    2004-01-01

    On the basis of investigating 9 counties (towns) in Yunnan Province of China, the species diversity and community structure of sucking lice on the body surface of small mammal hosts are studied in the paper. Species richness (S) is used to stand for the species diversity. The calculation of community diversity index and evenness are based on Shannon-Wiener's method. 2745 small mammals captured from the investigated sites belong to 10 families, 25 genera and 41 species in 5 orders (Rodentia, Insectivora, Scandentia, Logomorpha and Carnivora) while 18165 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 4 families, 6 genera and 22 species. The species of sucking lice are much less than the species of their hosts. Most species of small mammals have their fixed sucking lice on their body surface. One species of small mammals usually have few species of sucking lice (1 to 4 species). The close species of the hosts in the taxonomy are found to have the same or similar dominant species of sucking lice on their body surface. The results reveal that the species diversity of sucking lice on small mammals is very low with a very simple community structure. The results also imply there may be a close co-evolution relationship between the lice and the hosts.

  11. The power of social structure: how we became an intelligent lineage

    Science.gov (United States)

    de Sousa António, Marina Resendes; Schulze-Makuch, Dirk

    2011-01-01

    New findings pertinent to the human lineage origin (Ardipithecus ramidus) prompt a new analysis of the extrapolation of the social behavior of our closest relatives, the great apes, into human ‘natural social behavior’. With the new findings it becomes clear that human ancestors had very divergent social arrangements from the ones we observe today in our closest genetic relatives. The social structure of chimpanzees and gorillas is characterized by male competition. Aggression and the instigation of fear are common place. The morphology of A. ramidus points in the direction of a social system characterized by female-choice instead of male-male competition. This system tends to be characterized by reduced aggression levels, leading to more stable arrangements. It is postulated here that the social stability with accompanying group cohesion propitiated by this setting is favorable to the investment in more complex behaviors, the development of innovative approaches to solve familiar problems, an increase in exploratory behavior, and eventually higher intelligence and the use of sophisticated tools and technology. The concentration of research efforts into the study of social animals with similar social systems (e.g., New World social monkeys (Callitrichidae), social canids (Canidae) and social rodents (Rodentia)) are likely to provide new insights into the understanding of what factors determined our evolution into an intelligent species capable of advanced technology.

  12. A Revised Checklist of Chigger Mites (Acari: Trombiculidae) From Thailand, with the Description of Three New Species.

    Science.gov (United States)

    Chaisiri, Kittipong; Stekolnikov, Alexandr A; Makepeace, Benjamin L; Morand, Serge

    2016-03-01

    Chigger mites of Thailand were studied on the basis of larvae collected from 19 small mammal species (17 species of Rodentia, 1 species of Erinaceomorpha, and 1 species of Scandentia) and revision of published data. Samples of 38 trombiculid species were collected from 11 provinces. Three new species were described: Trombiculindus kosapani sp. nov., Helenicula naresuani sp. nov., and Walchia chavali sp. nov. Ten species were recorded in Thailand for the first time: Leptotrombidium sialkotense Vercammen-Grandjean and Langston, 1976; Leptotrombidium subangulare Wen and Xiang, 1984; Leptotrombidium tenompaki Stekolnikov, 2013; Leptotrombidium turdicola Vercammen-Grandjean and Langston, 1976; Leptotrombidium yunlingense Yu, Yang, Zhang and Hu, 1981; Lorillatum hekouensis Yu, Chen and Lin, 1996; Helenicula pilosa (Abonnenc and Taufflieb, 1957); Gahrliepia xiaowoi Wen and Xiang, 1984; Walchia minuscuta Chen, 1978; and Walchia ventralis (Womersley, 1952). In all, 99 chigger mite species were considered; the presence of 93 species was established in Thailand by original data or properly documented records in the scientific literature. Evidence for 64 species records of 147 from a previous checklist of Thai chiggers (Tanskul 1993) remains unknown. Distribution of chigger species by geographical regions of Thailand is discussed.

  13. New Aspidoderidae species parasite of Didelphis aurita (Mammalia: Didelphidae): a light and scanning electron microscopy approach.

    Science.gov (United States)

    Chagas-Moutinho, V A; Sant'anna, V; Oliveira-Menezes, A; De Souza, W

    2014-02-01

    Nematodes of the family Aspidoderidae (Nematoda: Heterakoidea) Skrjabin and Schikobalova, 1947, are widely distributed in the Americas. The family Aspidoderidae includes the subfamilies Aspidoderinae Skrjabin and Schikobalova, 1947, and Lauroiinae Skrjabin and Schikobalova, 1951. These two subfamilies are delineated by the presence or absence of cephalic cordons at the anterior region. The nematodes in the subfamily Aspidoderinae, which includes the genus AspidoderaRailliet and Henry, 1912, are represented by nematodes with anterior cephalic cordons at the anterior end. The nematodes of the genus AspidoderaRailliet and Henry, 1912, are found in the cecum and large intestine of mammals of the orders Edentata, Marsupialia and Rodentia. Species within this genus have many morphological similarities. The use of scanning electron microscopy allows the specific characterization of the species within this genus. In the present work, we describe a new species of Aspidodera parasite of the large intestine of Didelphis aurita (Mammalia: Didelphidae) Wied-Neuwied, 1826, collected from Cachoeiras de Macacu, Rio de Janeiro. The combination of light and scanning electron microscopy allowed us a detailed analysis of this nematode.

  14. Physiologic reference ranges for captive black-tailed prairie dogs (Cynomys ludovicianus).

    Science.gov (United States)

    Keckler, M Shannon; Gallardo-Romero, Nadia F; Langham, Gregory L; Damon, Inger K; Karem, Kevin L; Carroll, Darin S

    2010-05-01

    The black-tailed prairie dog (Cynomys ludovicianus) is a member of the order Rodentia and the family Sciuridae. Ecologically, prairie dogs are a keystone species in prairie ecology. This species is used as an animal model for human gallbladder disease and diseases caused by infection with Clostridium difficile, Yersinia pestis, Francisella tularensis, and most recently, Orthopoxvirus. Despite increasing numbers of prairie dogs used in research and kept as pets, few data are available on their baseline physiology in animal facility housing conditions. To establish baseline physiologic reference ranges, we designed a study using 18 wild-caught black-tailed prairie dogs. Telemetry data were analyzed to establish circadian rhythms for activity and temperature. In addition, hematologic and serum chemistry analyses were performed. Baseline measurements were used to establish the mean for each animal, which then were compiled and analyzed to determine the reference ranges. Here we present physiologic data on serum chemistry and hematology profiles, as well as weight, core body temperature, and daily activity patterns for black-tailed prairie dogs. These results reflect the use of multiple measurements from species- and age-matched prairie dogs and likely will be useful to ecologists, scientists interested in using this animal model in research, and veterinarians caring for pet prairie dogs.

  15. The Eurasian eagle-owl (Bubo bubo diet in the Trøndelag region (Central Norway

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    Obuch Ján

    2016-12-01

    Full Text Available Between 2008 and 2015 we collected pellets of the Eurasian eagle-owl (Bubo bubo in the Trøndelag region of central Norway and identified the food remains in these samples. We collected material at 45 sites with samples from a total of 76 nests. Some of the samples were from older and already abandoned nests, but at several sites we also found and collected fresh B. bubo pellets. In total 40,766 items of prey were identified from the osteological material. The most dominant food components were mammals (Mammalia, 25 species, 63.5%. The species representation of birds was very diverse (Aves, more than 150 species, 19.4%. Of amphibians (Amphibia, 1 6.8%, the well-represented species were Rana temporaria. Fish (Pisces, 0.3% were represented rarely, while invertebrates were represented only sporadically (Invertebrata, 0.05%. A special composition was found in the diet spectra of the mammals and birds in the mountainous areas at altitudes between 220-780 m above sea level. The highest proportion of frogs was found in areas in the proximity of the mainland shore. On the northern islands located near the coast a significant proportion of the B. bubo diet consisted of rodents (Rodentia. On the more isolated southern islands of Frøya, Hitra and Storfosna the main prey was sea birds, and of the mammals there were also hedgehogs and rats.

  16. The faunal composition and distribution of small mammals in Erlang Mountains%二郎山小型兽类区系及分布格局

    Institute of Scientific and Technical Information of China (English)

    孙治宇; 刘少英; 郭延蜀; 刘洋; 廖锐; 郭振伟

    2013-01-01

    From June to July in 2006 and May in 2011,the faunas and distribution of small mammals (Insectivora,Rodentia and Ochotonidae) in the Erlang Mountains was surveyed.We sampled small mammals using kill traps at five sites at elevations varying from 1 800 to 3 437 m,Within each site,we sampled along separate quadrates in different vegetation.In 4 550 trap nights,we captured 300 individuals representing 28 species,15 genera,6 families and 3 orders.There were 19 species on the east slope,all of which belonged to the Oriental realm.There were 17 species on the west slope,2 of which belonged to the Palaearctic realm,14 of which belonged to the Oriental realm,and 1 of which is widely distributed.The Himalayan-Hengduan mountains type is preponderant on both the east and the west slopes.The small mammals' species and quantity are the most in mountainside both the east and the west slope.The small mammals' combination and dominant species are different at different elevations and in different vegetation.

  17. Hystricognathy vs Sciurognathy in the Rodent Jaw: A New Morphometric Assessment of Hystricognathy Applied to the Living Fossil Laonastes (Diatomyidae)

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    Hautier, Lionel; Lebrun, Renaud; Saksiri, Soonchan; Michaux, Jacques; Vianey-Liaud, Monique; Marivaux, Laurent

    2011-01-01

    While exceptional for an intense diversification of lineages, the evolutionary history of the order Rodentia comprises only a limited number of morphological morphotypes for the mandible. This situation could partly explain the intense debates about the taxonomic position of the latest described member of this clade, the Laotian rock rat Laonastes aenigmamus (Diatomyidae). This discovery has re-launched the debate on the definition of the Hystricognathi suborder identified using the angle of the jaw relative to the plane of the incisors. Our study aims to end this ambiguity. For clarity, it became necessary to revisit the entire morphological diversity of the mandible in extant and extinct rodents. However, current and past rodent diversity brings out the limitations of the qualitative descriptive approach and highlights the need for a quantitative approach. Here, we present the first descriptive comparison of the masticatory apparatus within the Ctenohystrica clade, in combining classic comparative anatomy with morphometrical methods. First, we quantified the shape of the mandible in rodents using 3D landmarks. Then, the analysis of osteological features was compared to myological features in order to understand the biomechanical origin of this morphological diversity. Among the morphological variation observed, the mandible of Laonastes aenigmamus displays an intermediate association of features that could be considered neither as sciurognathous nor as hystricognathous. PMID:21490933

  18. Hystricognathy vs sciurognathy in the rodent jaw: a new morphometric assessment of hystricognathy applied to the living fossil Laonastes (Diatomyidae.

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    Lionel Hautier

    Full Text Available While exceptional for an intense diversification of lineages, the evolutionary history of the order Rodentia comprises only a limited number of morphological morphotypes for the mandible. This situation could partly explain the intense debates about the taxonomic position of the latest described member of this clade, the Laotian rock rat Laonastes aenigmamus (Diatomyidae. This discovery has re-launched the debate on the definition of the Hystricognathi suborder identified using the angle of the jaw relative to the plane of the incisors. Our study aims to end this ambiguity. For clarity, it became necessary to revisit the entire morphological diversity of the mandible in extant and extinct rodents. However, current and past rodent diversity brings out the limitations of the qualitative descriptive approach and highlights the need for a quantitative approach. Here, we present the first descriptive comparison of the masticatory apparatus within the Ctenohystrica clade, in combining classic comparative anatomy with morphometrical methods. First, we quantified the shape of the mandible in rodents using 3D landmarks. Then, the analysis of osteological features was compared to myological features in order to understand the biomechanical origin of this morphological diversity. Among the morphological variation observed, the mandible of Laonastes aenigmamus displays an intermediate association of features that could be considered neither as sciurognathous nor as hystricognathous.

  19. Ecological diversity of Trypanosoma cruzi transmission in the Amazon basin. The main scenaries in the Brazilian Amazon.

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    Coura, J R; Junqueira, A C V

    2015-11-01

    The ecological diversity of Trypanosoma cruzi transmission in the Brazilian Amazon region is directly interlinked with the parasite's extensive reservoir, composed of 33 species of wild mammals within the following orders: Marsupialia, Chiroptera, Rodentia, Xenarthra, Carnivora and Primates; and of 16 species of wild triatomines, of which ten may be infected with T. cruzi. Four scenarios for the diversity of T. cruzi transmission in the Brazilian Amazon region are evident: (i) T. cruzi transmission between vectors and wild mammals, which is characterized as a wild enzooty encompassing the entire Amazon basin; (ii) accidental T. cruzi transmission from vectors and wild mammals to humans, when they invade the wild ecotope or when these vectors and wild mammals invade human homes; (iii) occupational Chagas disease among piassava (Leopoldinia piassaba) palm fiber gatherers, transmitted by the vector Rhodnius brethesi, for which these palm trees are the specific ecotope; (IV) oral T. cruzi transmission to humans through food contamination, particularly in juices from plants such as assai, which today is considered to be endemic in the Brazilian Amazon region, with more than 1500 cases notified.

  20. Evolution of genome organizations of squirrels (Sciuridae) revealed by cross-species chromosome painting.

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    Li, Tangliang; O'Brien, Patricia C M; Biltueva, Larisa; Fu, Beiyuan; Wang, Jinhuan; Nie, Wenhui; Ferguson-Smith, Malcolm A; Graphodatsky, Alexander S; Yang, Fengtang

    2004-01-01

    With complete sets of chromosome-specific painting probes derived from flow-sorted chromosomes of human and grey squirrel (Sciurus carolinensis), the whole genome homologies between human and representatives of tree squirrels (Sciurus carolinensis, Callosciurus erythraeus), flying squirrels (Petaurista albiventer) and chipmunks (Tamias sibiricus) have been defined by cross-species chromosome painting. The results show that, unlike the highly rearranged karyotypes of mouse and rat, the karyotypes of squirrels are highly conserved. Two methods have been used to reconstruct the genome phylogeny of squirrels with the laboratory rabbit (Oryctolagus cuniculus) as the out-group: (1) phylogenetic analysis by parsimony using chromosomal characters identified by comparative cytogenetic approaches; (2) mapping the genome rearrangements onto recently published sequence-based molecular trees. Our chromosome painting results, in combination with molecular data, show that flying squirrels are phylogenetically close to New World tree squirrels. Chromosome painting and G-banding comparisons place chipmunks (Tamias sibiricus ), with a derived karyotype, outside the clade comprising tree and flying squirrels. The superorder Glires (orde Rodentia + order Lagomorpha) is firmly supported by two conserved syntenic associations between human chromosomes 1 and 10p homologues, and between 9 and 11 homologues.

  1. Guerrerostrongylus marginalis n. sp. (Trichostrongyloidea: Heligmonellidae from the Guianan arboreal mouse (Oecomys auyantepui from French Guiana

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    Weirich Jessica M.

    2016-01-01

    Full Text Available Based on the number and arrangement of cuticular ridges and configuration of the dorsal ray, nematode specimens collected from the small intestine of eight Guianan arboreal mice, Oecomys auyantepui (Rodentia: Sigmodontinae, in French Guiana are herein described and characterized. Guerrerostrongylus marginalis n. sp. (Heligmosomoidea: Heligmonellidae shows a synlophe consisting of more than 40 ridges and a unique bursal arrangement with ray 8 (externo-dorsal extending to the edge of the bursal margin, and appearing more prominent than the dorsal ray. This bursal arrangement is common in members of Hassalstrongylus Durette-Desset, 1971, but uncommon in the other four species in Guerrerostrongylus Sutton & Durette-Desset, 1991. The placement of the new species in Guerrerostrongylus is based on the number and nature of cuticular ridges and the ray arrangement and symmetry of the caudal bursa. Diagnostic characteristics of Guerrerostrongylus marginalis n. sp. include the length of ray 8 relative to bursal margin, the relative size of the spicules and vestibule, and the number of eggs in the uterus. We propose an amendment to the generic diagnosis of Guerrerostrongylus to modify the characters of the long rays 6 (postero-lateral, rays 8 (externo-dorsal, and dorsal ray as diagnostic, since at least ray 6 appears to be short in two different species in the genus, namely G. ulysi Digiani, Notarnicola & Navone, 2012 and G. marginalis n. sp.

  2. Nuevos datos paleontológicos del Pleistoceno en el Valle del Manzanares (Madrid, España: Los micromamíferos del yacimiento del Arenero de Arriaga

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    Sesé, Carmen

    2013-12-01

    Full Text Available The micromammals from the archaeological site of the Arenero de Arriaga from the Manzanares Valley are here described. They are the Soricomorpha: Crocidura sp. and Talpa sp., the Rodentia: Eliomys quercinus quercinus, Apodemus sp., Microtus brecciensis, Microtus arvalis, Microtus duodecimcostatus and Arvicola aff. sapidus, and the Lagomorpha: Oryctolagus cuniculus. The faunal association and the evolutionary state of Microtus brecciensis and Arvicola aff. sapidus, suggest an age of the end of the Middle Pleistocene. It also indicates the existence of different biotopes: riparian, moist and dry meadows, and forest, and a temperate climate similar to the present-day climate of the Meseta.Se describe la asociación de micromamíferos del yacimiento achelense del Arenero de Arriaga del valle del Manzanares constituida por los soricomorfos: Crocidura sp. y Talpa sp., los roedores: Eliomys quercinus quercinus, Apodemus sp., Microtus brecciensis, Microtus arvalis, Microtus duodecimcostatus y Arvicola aff. sapidus, y el lagomorfo: Oryctolagus cuniculus. La asociación faunística y el estadio evolutivo de Microtus brecciensis y Arvicola aff. sapidus, indican una edad del final del Pleistoceno Medio. La asociación de micromamíferos sugiere la existencia de varios biotopos representados: ripícola, praderas húmedas y secas, y bosque, y un clima templado similar al actual de la Meseta.

  3. Molecular and paleontological evidence for a post-Cretaceous origin of rodents.

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    Shaoyuan Wu

    Full Text Available The timing of the origin and diversification of rodents remains controversial, due to conflicting results from molecular clocks and paleontological data. The fossil record tends to support an early Cenozoic origin of crown-group rodents. In contrast, most molecular studies place the origin and initial diversification of crown-Rodentia deep in the Cretaceous, although some molecular analyses have recovered estimated divergence times that are more compatible with the fossil record. Here we attempt to resolve this conflict by carrying out a molecular clock investigation based on a nine-gene sequence dataset and a novel set of seven fossil constraints, including two new rodent records (the earliest known representatives of Cardiocraniinae and Dipodinae. Our results indicate that rodents originated around 61.7-62.4 Ma, shortly after the Cretaceous/Paleogene (K/Pg boundary, and diversified at the intraordinal level around 57.7-58.9 Ma. These estimates are broadly consistent with the paleontological record, but challenge previous molecular studies that place the origin and early diversification of rodents in the Cretaceous. This study demonstrates that, with reliable fossil constraints, the incompatibility between paleontological and molecular estimates of rodent divergence times can be eliminated using currently available tools and genetic markers. Similar conflicts between molecular and paleontological evidence bedevil attempts to establish the origination times of other placental groups. The example of the present study suggests that more reliable fossil calibration points may represent the key to resolving these controversies.

  4. Bartonella infection in small mammals and their ectoparasites in Lithuania.

    Science.gov (United States)

    Lipatova, Indre; Paulauskas, Algimantas; Puraite, Irma; Radzijevskaja, Jana; Balciauskas, Linas; Gedminas, Vaclovas

    2015-01-01

    The Bartonella pathogen is an emerging zoonotic agent. Epidemiological studies worldwide have demonstrated that small mammals are reservoir hosts of Bartonella spp. and their ectoparasites are potential vectors. The aim of this study was to investigate the prevalence of Bartonella infections in small mammals (Rodentia, Insectivora) and their ectoparasites (fleas and ticks) in Lithuania. A total of 430 small mammals representing nine species were captured with live-traps in Lithuania during 2013-2014. A total of 151 fleas representing eight species were collected from 109 (25.8%) small mammals. Five hundred and seventy ticks (Ixodes ricinus) were collected from 68 (16.1%) small mammals. Bartonella DNA was detected in 102 (23.7%) small mammals, 44 (29.1%) fleas and five (3.7%) pooled tick samples. Sequence analysis of 16S-23S rRNA ITS region showed that sequences were identical or similar to Bartonella grahamii, Bartonella taylorii and Bartonella rochalimae. This study is the first investigating the distribution and diversity of Bartonella species in small mammals and their ectoparasites in Lithuania. B. grahamii, B. taylorii, and B. rochalimae were detected in small mammals and their fleas, and B. grahamii in ticks obtained from small mammals.

  5. PREVALENCE AND DIVERSITY OF BARTONELLA SPECIES IN WILD SMALL MAMMALS IN ASIA.

    Science.gov (United States)

    Kim, Kyeong Soon; Inoue, Kai; Kabeya, Hidenori; Sato, Shingo; Takada, Tomoe; Pangjai, Decha; Chiu, Shih-Hui; Fujita, Hiromi; Kawabata, Hiroki; Takada, Nobuhiro; Kariwa, Hiroaki; Maruyama, Soichi

    2016-01-01

    We collected 641 small mammals belonging to 17 species of Rodentia and four species of Soricomorpha in Japan, Korea, Russia, Taiwan, and Thailand and investigated the prevalence and genetic diversity of Bartonella species. Apodemus (field mice) and Rattus (rats) were the most-common genera captured, making up 56.0% and 23.1% of the total specimens, respectively. Bartonellae were isolated from 54.6% of the collected animals, and the prevalence varied depending on the host species and the country of origin. The isolates were identified to the species level based on gltA and rpoB sequences. Although most Bartonella species were shared by more than two host species, the distribution patterns of Bartonella species clearly differed among the four most-common host genera: Apodemus, Rattus, Myodes (voles), and Suncus (shrews). The predominant Bartonella species were Bartonella grahamii in Apodemus, Bartonella tribocorum in Rattus, B. grahamii and Bartonella taylorii in Myodes, and an unclassified Bartonella sp. in Suncus.

  6. Fluctuating Asymmetry of Craniological Features of Small Mammals as a Reflection of Heterogeneity of Natural Populations

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    Elena Shadrina

    2016-11-01

    Full Text Available Fluctuating asymmetry (FA in nine species of small mammals (Insectivora and Rodentia was estimated using 10 cranial features (foramina for nerves and blood vessels. The main criterion was the occurrence of the fluctuating asymmetry manifestations (OFAM. A total of 2300 skulls collected in the taiga and forest-tundra of Yakutia (Northeast Asia were examined. The examined species are characterized by comparable OFAM values in the vast territories of the taiga zone; on the ecological periphery of the range an increased FA level is registered. Asymmetric manifestations in analyzed features are equally likely to occur in males and females. OFAM values in juveniles are higher than in adults; this difference is more pronounced on the periphery of the geographic range. Among juveniles, lower FA levels are observed in individuals that have bred. It can be surmised that the risk of elimination of individuals with high FA levels increases in stressful periods (active reproduction and winter. In conditions that are close to optimal, populations demonstrate relatively homogeneous FA levels, while on the periphery of the area an increase in occurrence of disturbances in developmental stability is observed, which leads, on one hand, to higher average FA for the population and, on the other hand, to heterogeneity of the population in this parameter.

  7. Microsatellite-encoded domain in rodent Sry functions as a genetic capacitor to enable the rapid evolution of biological novelty.

    Science.gov (United States)

    Chen, Yen-Shan; Racca, Joseph D; Sequeira, Paul W; Phillips, Nelson B; Weiss, Michael A

    2013-08-13

    The male program of therian mammals is determined by Sry, a transcription factor encoded by the Y chromosome. Specific DNA binding is mediated by a high mobility group (HMG) box. Expression of Sry in the gonadal ridge activates a Sox9-dependent gene regulatory network leading to testis formation. A subset of Sry alleles in superfamily Muroidea (order Rodentia) is remarkable for insertion of an unstable DNA microsatellite, most commonly encoding (as in mice) a CAG repeat-associated glutamine-rich domain. We provide evidence, based on an embryonic pre-Sertoli cell line, that this domain functions at a threshold length as a genetic capacitor to facilitate accumulation of variation elsewhere in the protein, including the HMG box. The glutamine-rich domain compensates for otherwise deleterious substitutions in the box and absence of nonbox phosphorylation sites to ensure occupancy of DNA target sites. Such compensation enables activation of a male transcriptional program despite perturbations to the box. Whereas human SRY requires nucleocytoplasmic shuttling and coupled phosphorylation, mouse Sry contains a defective nuclear export signal analogous to a variant human SRY associated with inherited sex reversal. We propose that the rodent glutamine-rich domain has (i) fostered accumulation of cryptic intragenic variation and (ii) enabled unmasking of such variation due to DNA replicative slippage. This model highlights genomic contingency as a source of protein novelty at the edge of developmental ambiguity and may underlie emergence of non-Sry-dependent sex determination in the radiation of Muroidea.

  8. Rodent Species Distribution and Hantavirus Seroprevalence in Residential and Forested areas of Sarawak, Malaysia.

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    Hamdan, Nur Elfieyra Syazana; Ng, Yee Ling; Lee, Wei Bin; Tan, Cheng Siang; Khan, Faisal Ali Anwarali; Chong, Yee Ling

    2017-01-01

    Rodents belong to the order Rodentia, which consists of three families in Borneo (i.e., Muridae, Sciuridae and Hystricidae). These include rats, mice, squirrels, and porcupines. They are widespread throughout the world and considered pests that harm humans and livestock. Some rodent species are natural reservoirs of hantaviruses (Family: Bunyaviridae) that can cause zoonotic diseases in humans. Although hantavirus seropositive human sera were reported in Peninsular Malaysia in the early 1980s, information on their infection in rodent species in Malaysia is still lacking. The rodent populations in residential and forested areas in Sarawak were sampled. A total of 108 individuals from 15 species of rodents were collected in residential (n = 44) and forested ( n = 64) areas. The species diversity of rodents in forested areas was significantly higher (H = 2.2342) compared to rodents in residential areas (H = 0.64715) (p rodent populations in Sarawak, East Malaysia. The results suggested that hantavirus was not circulating in the studied rodent populations in Sarawak, or it was otherwise at a low prevalence that is below the detection threshold. It is important to remain vigilant because of the zoonotic potential of this virus and its severe disease outcome. Further studies, such as molecular detection of viral genetic materials, are needed to fully assess the risk of hantavirus infection in rodents and humans in this region of Malaysia.

  9. REVISED AND COMMENTED CHECKLIST OF MAMMAL SPECIES OF THE ROMANIAN FAUNA

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    Dumitru Murariu

    2015-12-01

    Full Text Available Due to the permanent influences of different factors (habitat degradation and fragmentation, deforestation, infrastructure and urbanization, natural extension or decreasing of some species’ distribution, increasing number of alien species etc., from time to time the faunistic structure of a certain area is changing. As a result of the permanent and increasing anthropic and invasive species’ pressure, our previous checklist of recent mammals from Romania (since 1984 became out of date. A number of 108 taxa are mentioned in this checklist, representing 7 orders of mammals: Insectivora (10 species, Chiroptera (30 sp., Lagomorpha (2 sp., Rodentia (35 sp., Cetacea (3 sp., Carnivora (19 sp., Artiodactyla (8 sp.. In this list are mentioned the scientific and vernacular names (in Romanian and English languages, species distribution and conservation status, according to the Romanian regulations. Thus, only 21 species have stable populations while 76 have populations in decline or in drastic decline. Other categories are not evaluated or even present an increase in their population.

  10. Analyzing the impact of conflictive dental characters on the phylogeny of octodontoid rodents

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    Adriana M. Candela

    2016-06-01

    Full Text Available Systematics of fossil octodontoids (Rodentia, Caviomorpha is in great part based on insights into the knowledge of teeth, making the step of dental characterization certainly relevant for the evolutionary reconstruction of these rodents. Different homology hypotheses were proposed for the same tooth structures, a fact that indicates the importance of knowing on which criteria the dental characters supporting the classifications were based. In this line, I evaluate the step of characterization of certain conflictive molar characters previously used, and their impact on phylogeny of octodontoids. I explore which the criteria followed to propose the hypotheses of correspondences for these characters are in light of the anatomical evidence. Based on the outcome of phylogenetic trees obtained previously, I analyze if the evolutionary transformations are compatible with character states observed in the terminals. New cladistic analyses based on recoded molar characters indicate that, unlike results recently obtained, the unorthodox position of Sallamys, Protadelphomys, and Willidewu as basal ctenomyines is not recovered. The position of Caviocricetus, Acarechimys–Neophanomysas as Octodontinae is not maintained. These results indicate that reanalyses of conflictive dental characters, scrutinizing data matrices, are particularly necessary to evaluate the current controversy on the phylogeny of octodontoids. Lower molar character definition and character states delimitation in octodontoids, being relevant to phylogenetic reconstruction, should be founded on anatomical examination, following explicit criteria of homology. Alternative hypotheses of “primary homology” proposed for the same molar traits in octodontoids indicate that each main group of caviomorphs requires its own anatomical study.

  11. KEANEKARAGAMAN FAUNA PARASIT PADA MAMALIA KECIL DI KAWASAN TESSO-NILO, PROPINSI RIAU

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    Achmad Saim

    2012-11-01

    Full Text Available A total of 1712 specimens (17 species of parasites were found on 25 specimens (six species small mammals in Tesso-Nilo areas, Riau Province, i.e.: two Amblyomma testudinarium on Maxomys surifer, eight Dermacentor spp. on Maxomys surifer, Maxomys whiteheadi, Sundomys muelleri, three Haemaphysalis sp on Tupaia glis, two Ixodes sp on Maxomys surifer, 81 Demodex sp on Maxomys rajah, Maxomys surifer, Maxomys whiteheadi, 42 Echinolaelaps echidninus on Maxomys rajah, Maxomys surifer, Maxomys whiteheadi, 1.430 Laelaps spp (two species on Maxomys rajah, Maxomys surifer, Maxomys whiteheadi, S. muelleri, 131  specimens (two species trombiculids on Maxomys surifer, Maxomys whiteheadi, S. muelleri, T. glis, one louse of Polyplax sp. on Maxomys surifer, four fleas (two Ceratophyllus sp on T. glis and Xenopsylla cheopis on Maxomys whiteheadi; two batflies of Nycteribiidae on Balionycteris maculata, two Hydatigera taeniaeformis in Maxomys rajah, two Hymenolepis sp on S. muelleri, and two Moniliformis sp in Maxomys rajah. It was found that  25 hosts were infected out of 26 collected hosts (96.15%, the pattern of endo and ectoparasites were 1-5 species ectoparasites or 1-2 species endoparasites in each host, while Shannon Wiener Index was 1.92 for ectoparasites and 1.58 for endoparasites. Other hosts, distribution and  potency in ecosystem of each species were discussed.  Keywords: Acarina, Insecta, Helminthes, Rodentia, Scandentia, Chiroptera, Parasites.

  12. Evolution of recombination in eutherian mammals: insights into mechanisms that affect recombination rates and crossover interference.

    Science.gov (United States)

    Segura, Joana; Ferretti, Luca; Ramos-Onsins, Sebastián; Capilla, Laia; Farré, Marta; Reis, Fernanda; Oliver-Bonet, Maria; Fernández-Bellón, Hugo; Garcia, Francisca; Garcia-Caldés, Montserrat; Robinson, Terence J; Ruiz-Herrera, Aurora

    2013-11-22

    Recombination allows faithful chromosomal segregation during meiosis and contributes to the production of new heritable allelic variants that are essential for the maintenance of genetic diversity. Therefore, an appreciation of how this variation is created and maintained is of critical importance to our understanding of biodiversity and evolutionary change. Here, we analysed the recombination features from species representing the major eutherian taxonomic groups Afrotheria, Rodentia, Primates and Carnivora to better understand the dynamics of mammalian recombination. Our results suggest a phylogenetic component in recombination rates (RRs), which appears to be directional, strongly punctuated and subject to selection. Species that diversified earlier in the evolutionary tree have lower RRs than those from more derived phylogenetic branches. Furthermore, chromosome-specific recombination maps in distantly related taxa show that crossover interference is especially weak in the species with highest RRs detected thus far, the tiger. This is the first example of a mammalian species exhibiting such low levels of crossover interference, highlighting the uniqueness of this species and its relevance for the study of the mechanisms controlling crossover formation, distribution and resolution.

  13. Frequent expansions of the bitter taste receptor gene repertoire during evolution of mammals in the Euarchontoglires clade.

    Science.gov (United States)

    Hayakawa, Takashi; Suzuki-Hashido, Nami; Matsui, Atsushi; Go, Yasuhiro

    2014-08-01

    Genome studies of mammals in the superorder Euarchontoglires (a clade that comprises the orders Primates, Dermoptera, Scandentia, Rodentia, and Lagomorpha) are important for understanding the biological features of humans, particularly studies of medical model animals such as macaques and mice. Furthermore, the dynamic ecoevolutionary signatures of Euarchontoglires genomes may be discovered because many species in this clade are characterized by their successful adaptive radiation to various ecological niches. In this study, we investigated the evolutionary trajectory of bitter taste receptor genes (TAS2Rs) in 28 Euarchontoglires species based on homology searches of 39 whole-genome assemblies. The Euarchontoglires species possessed variable numbers of intact TAS2Rs, which ranged from 16 to 40, and their last common ancestor had at least 26 intact TAS2Rs. The gene tree showed that there have been at least seven lineage-specific events involving massive gene duplications. Gene duplications were particularly evident in the ancestral branches of anthropoids (the anthropoid cluster), which may have promoted the adaptive evolution of anthropoid characteristics, such as a trade-off between olfaction and other senses and the development of herbivorous characteristics. Subsequent whole-gene deletions of anthropoid cluster TAS2Rs in hominoid species suggest ongoing ectopic homologous recombination in the anthropoid cluster. These findings provide insights into the roles of adaptive sensory evolution in various ecological niches and important clues related to the molecular mechanisms that underlie taste diversity in Euarchontoglires mammalian species, including humans.

  14. Checklist of helminths found in Patagonian wild mammals.

    Science.gov (United States)

    Fugassa, Martin H

    2015-09-03

    Using available reports, a checklist of the recorded helminth parasites of wild mammals from Patagonia was generated. Records of parasites found in Patagonia were included, together with records from mammals in áreas outside of Patagonia but whose range extends into Patagonia. Information about the host, localities, and references were also included. A total of 1323 records (224 Cestoda, 167 Trematoda, 894 Nematoda, 34 Acanthocephala, and 4 Pentastomida) belonging to 452 helminth species (77 Cestoda, 76 Trematoda, 277 Nematoda, 21 Acanthocephala, and 1 Pentastomida) found in 57 native mammals (22 Rodentia, 4 Didelphimorphia 1 Microbiotheria, 7 Chiroptera, 5 Cingulata, and 13 Carnivora) were listed. However, only 10.6 % of the reports were conducted on samples from Patagonia and corresponded to 25% of mammals in the region. In addition, many studies were made on a few species and, for example, 52% corresponded to studies made on Lama guanicoe. This suggests the need to increase efforts to know the parasitic fauna in a peculiar region as is the Patagonia. This is the first compilation of the helminth parasites of mammals in Argentine Patagonia and is important for parasitological and paleoparasitological studies.

  15. Abrocomaphthirus hoplai, a new genus and species of sucking louse from Chile and its relevance to zoogeography.

    Science.gov (United States)

    Durden, L A; Webb, J P

    1999-10-01

    Both sexes of Abrocomaphthirus hoplai, new genus and new species (Anoplura: Polyplacidae), are described and illustrated. The endemic Chilean chinchilla rat Abrocoma bennetti Waterhouse (Rodentia: Abrocomidae) is the type host. The definition of the family Polyplacidae is amended to accommodate the new genus. Polyplax longa (Werneck), also referred to in the literature as Neohaematopinus longus Werneck, is reassigned to Abrocomaphthirus. The host of A. longus comb.n., is Abrocoma cinerea Thomas, another chinchilla rat, which inhabits parts of Argentina, Bolivia, Chile and Peru. The erection of Abrocomaphthirus as a distinct genus has important zoogeographical and evolutionary implications. The tenuous anomaly of P. longa being the sole native representative of the genus Polyplax in South America, possibly with African affinities, is now refuted. Instead, partial colonization of the neotropics by native species of both Polyplax and Neohaematopinus appears to have been relatively recent and from North America. The phylogenetic affinities of Abrocomaphthirus are unknown, but it appears to be closely related to other, more ancient, native South American polyplacid louse genera, such as Cuyana, Eulinognathus, Galeophthirus, and Lagidiophthirus. Arguments are presented in support of an ancestral zoogeographical link to Africa for these louse genera.

  16. The wildlife research & rescue programme for mammals at Hulu Terengganu Hydroelectric Project (HTHEP), Terengganu, Peninsular Malaysia

    Science.gov (United States)

    Nur-Syuhada, N.; Magintan, D.; Siti-Hajar, A. R.; Aisah, M. S.; Shukor, M. N.

    2016-11-01

    During the inundation of the Hulu Terengganu Hydroelectric Project in October 2014, a wildlife rescue programme was conducted to rescue animals found trapped within the expanding 61.6 km2 reservoir. A total of 244 mammals from 30 species, representing 12 families were rescued by various methods included baited live trapping, catchpoles, hoop nets and by hand. The order Rodentia recorded the highest amount of rescued individuals at 20.9%, followed by Primate (18.9), Dermoptera (11.1), Carnivora (0.8) and Pholidota (0.4). The genus Rattus recorded the highest individuals rescued (51 individuals) probably due to the rapid clear-cut logging of the forest prior to inundation. Notable mammals of high conservational value rescued included Manis javanicus (Pangolin), Presbytis melalophos siamensis (Mitred Leaf Monkey), Trachypithecus obscurus (Dusky Leaf Monkey), Hylobates lar (White Handed Gibbon), Nycticebus coucang (Slow Loris), Galeopterus variegatus (Sunda Colugo), Callosciurus nigrovittatus (Sunda Black-banded Squirrel), Ratufa spp. (Giant Squirrels), and Sundasciurus hippurus (Horse-tailed Squirrel). Various data and biological samples were collected from the mammals rescued prior to their release at the nearest forest reserves. Rescue operation enabled the inventory and comprehensive data collection of various arboreal and rare mammal species that are hard to capture using the traditional survey method.

  17. More Novel Hantaviruses and Diversifying Reservoir Hosts — Time for Development of Reservoir-Derived Cell Culture Models?

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    Isabella Eckerle

    2014-02-01

    Full Text Available Due to novel, improved and high-throughput detection methods, there is a plethora of newly identified viruses within the genus Hantavirus. Furthermore, reservoir host species are increasingly recognized besides representatives of the order Rodentia, now including members of the mammalian orders Soricomorpha/Eulipotyphla and Chiroptera. Despite the great interest created by emerging zoonotic viruses, there is still a gross lack of in vitro models, which reflect the exclusive host adaptation of most zoonotic viruses. The usually narrow host range and genetic diversity of hantaviruses make them an exciting candidate for studying virus-host interactions on a cellular level. To do so, well-characterized reservoir cell lines covering a wide range of bat, insectivore and rodent species are essential. Most currently available cell culture models display a heterologous virus-host relationship and are therefore only of limited value. Here, we review the recently established approaches to generate reservoir-derived cell culture models for the in vitro study of virus-host interactions. These successfully used model systems almost exclusively originate from bats and bat-borne viruses other than hantaviruses. Therefore we propose a parallel approach for research on rodent- and insectivore-borne hantaviruses, taking the generation of novel rodent and insectivore cell lines from wildlife species into account. These cell lines would be also valuable for studies on further rodent-borne viruses, such as orthopox- and arenaviruses.

  18. Distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan, China

    Institute of Scientific and Technical Information of China (English)

    XU Xiang; GUAN Ya-yi; TIAN Tian; WU Wei-ping; WANG Qian; HUANG Yan; LI Guang-qing; WANG Li-ying

    2011-01-01

    Background The rodentia and lagomorpha animals are the intermediate hosts of Echinococcus multilocularis, their distribution and infection of this parasite may facilitate the infection of definitive hosts such as dogs. The aim of this study was to determine the distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan, China.Methods A systematic sampling method was used to investigate the density of burrows of rodents and lagomorphs at 97 pasture sites in winter and summer pastureland and remote sensing (RS) technology was used to correlate their densities to the distribution of these animals in different landscape types.Results Based on the densities of Ochotona curzoniae, Microtus fuscus (dependent variable) and their burrow densities (independent variable) in survey points, regression equations were fitted respectively (Ochotona curzoniae, P<0.0001, R2=0.8705; Microtus fuscus, P <0.0001, R2=0.9736). Their burrow density in summer pastureland was higher than in winter pastureland (F=36.65, P <0.0001). The burrow densities of Ochotona curzoniae and Microtus fuscus in bareland and half-bareland are higher than in grassland (F=7.73, P <0.001).Conclusions The regression relationship between the densities of Ochotona curzoniae and Microtus fuscus and their burrow densities indicate that the burrow densities could reflect the animal densities and that the burrow density was greater in summer pastureland than in winter pastureland. The main distribution areas of the intermediate hosts were in bareland and half-bareland.

  19. Coordinated scaling of cortical and cerebellar numbers of neurons

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    Suzana Herculano-Houzel

    2010-03-01

    Full Text Available While larger brains possess concertedly larger cerebral cortices and cerebella, the relative size of the cerebral cortex increases with brain size, but relative cerebellar size does not. In the absence of data on numbers of neurons in these structures, this discrepancy has been used to dispute the hypothesis that the cerebral cortex and cerebellum function and have evolved in concert and to support a trend towards neocorticalization in evolution. However, the rationale for interpreting changes in absolute and relative size of the cerebral cortex and cerebellum relies on the assumption that they reflect absolute and relative numbers of neurons in these structures across all species – an assumption that our recent studies have shown to be flawed. Here I show for the first time that the numbers of neurons in the cerebral cortex and cerebellum are directly correlated across 19 mammalian species of 4 different orders, including humans, and increase concertedly in a similar fashion both within and across the orders Eulipotyphla (Insectivora, Rodentia, Scandentia and Primata, such that on average a ratio of 3.6 neurons in the cerebellum to every neuron in the cerebral cortex is maintained across species. This coordinated scaling of cortical and cerebellar numbers of neurons provides direct evidence in favor of concerted function, scaling and evolution of these brain structures, and suggests that the common notion that equates cognitive advancement with neocortical expansion should be revisited to consider in its stead the coordinated scaling of neocortex and cerebellum as a functional ensemble.

  20. Epidemiology of leptospirosis at Sorocaba Zoo, São Paulo state, Southeastern Brazil

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    Leila S. Ullmann

    2012-11-01

    Full Text Available Leptospirosis is considered a worldwide distributed zoonosis, caused by the bacteria Leptospira spp. Since several species of wildlife animals are reportedly reservoirs, the aim of the present study was to know the epidemiology of leptospirosis at the Sorocaba Zoo, Southern Brazil. Serum samples of wild mammals from Artiodactyla, Carnivora, Didelphimorphia, Diprotodontia, Perissodactyla, Pilosa, Primates, Proboscidea and Rodentia orders, kept in captivity as well as from zoological staff were assayed by microscopic agglutination test (MAT. Whole blood, urine and tissue samples from wild mammals and synanthropic animals were assayed by polymerase chain reaction (PCR. An epidemiological survey was applied to evaluate the risk factors for animal infection and staff level of knowledge on leptospirosis. A total of 13/229 (5.68%; CI95% 3.37-9.47% serum samples from wild mammals were reagent on MAT. Serology from synanthropic animals, zoo staff and molecular analysis of animal samples were all negative. Leptospirosis knowledge of zoo park staff was considered medium. In conclusion, leptospiral infection occurs at the studied zoo but due to the low occurrence found, the lowest reported in literature, wild captive mammals do not act as source of infection of leptospirosis to other animals and human beings.

  1. Molecular and paleontological evidence for a post-Cretaceous origin of rodents.

    Science.gov (United States)

    Wu, Shaoyuan; Wu, Wenyu; Zhang, Fuchun; Ye, Jie; Ni, Xijun; Sun, Jimin; Edwards, Scott V; Meng, Jin; Organ, Chris L

    2012-01-01

    The timing of the origin and diversification of rodents remains controversial, due to conflicting results from molecular clocks and paleontological data. The fossil record tends to support an early Cenozoic origin of crown-group rodents. In contrast, most molecular studies place the origin and initial diversification of crown-Rodentia deep in the Cretaceous, although some molecular analyses have recovered estimated divergence times that are more compatible with the fossil record. Here we attempt to resolve this conflict by carrying out a molecular clock investigation based on a nine-gene sequence dataset and a novel set of seven fossil constraints, including two new rodent records (the earliest known representatives of Cardiocraniinae and Dipodinae). Our results indicate that rodents originated around 61.7-62.4 Ma, shortly after the Cretaceous/Paleogene (K/Pg) boundary, and diversified at the intraordinal level around 57.7-58.9 Ma. These estimates are broadly consistent with the paleontological record, but challenge previous molecular studies that place the origin and early diversification of rodents in the Cretaceous. This study demonstrates that, with reliable fossil constraints, the incompatibility between paleontological and molecular estimates of rodent divergence times can be eliminated using currently available tools and genetic markers. Similar conflicts between molecular and paleontological evidence bedevil attempts to establish the origination times of other placental groups. The example of the present study suggests that more reliable fossil calibration points may represent the key to resolving these controversies.

  2. Jumping and gliding rodents: mitogenomic affinities of Pedetidae and Anomaluridae deduced from an RNA-Seq approach.

    Science.gov (United States)

    Fabre, Pierre-Henri; Jønsson, Knud A; Douzery, Emmanuel J P

    2013-12-01

    An RNA-Seq strategy was used to obtain the complete set of protein-coding mitochondrial genes from two rodent taxa. Thanks to the next generation sequencing (NGS) 454 approach, we determined the complete mitochondrial DNA genome from Graphiurus kelleni (Mammalia: Rodentia: Gliridae) and partial mitogenome from Pedetes capensis (Pedetidae), and compared them with published rodent and outgroup mitogenomes. We finished the mitogenome sequencing by a series of amplicons using conserved PCR primers to fill the gaps corresponding to tRNA, rRNA and control regions. Phylogenetic analyses of the mitogenomes suggest a well-supported rodent phylogeny in agreement with nuclear gene trees. Pedetes groups with Anomalurus into the clade Anomaluromorpha, while Graphiurus branches within the squirrel-related clade. Moreover, Pedetes+Anomalurus branch with Castor into the mouse-related clade. Our study demonstrates the utility of NGS for obtaining new mitochondrial genomes as well as the importance of choosing adequate models of sequence evolution to infer the phylogeny of rodents.

  3. Environmental Survey Report for ORNL: Small Mammal Abundance and Distribution Survey Oak Ridge National Environmental Research Park 2009 - 2010

    Energy Technology Data Exchange (ETDEWEB)

    Giffen, Neil R [ORNL; Reasor, R. Scott [Oak Ridge Institute for Science and Education (ORISE); Campbell, Claire L. [Oak Ridge Institute for Science and Education (ORISE)

    2009-12-01

    Sherman and pitfall traps. In total 227 small mammals representing nine species were captured during the course of the study. The most common species found in the study was the white-footed mouse (Peromyscus leucopus). The least common species found were the deer mouse (Peromyscus maniculatus), meadow jumping mouse (Zapus hudsonius), woodland vole (Microtus pinetorum), and northern short-tailed shrew (Blarina brevicauda).

  4. Diversidad y composición de murciélagos en los bosques montanos del Santuario Nacional Pampa Hermosa, Junín, Perú

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    Edith Arias

    2016-08-01

    Full Text Available El Santuario Nacional Pampa Hermosa (SNPH es un área protegida importante debido a que protege los relictos de los bosques montanos de las Yungas centrales del Perú, donde los estudios de la diversidad de murciélagos son escasos. Nuestro objetivo fue documentar la diversidad y composición de los murciélagos del SNPH y compararlo con otros bosques de las Yungas peruanas en el rango de 1200 – 2000 m. Se evaluaron cuatro localidades: Podocarpus (1900 m, Los Cedros (1600 m, Santa Isabel (1450 m y Nueva Italia (1370 m. Se registraron 36 especies de murciélagos en las familias Phyllostomidae (30 spp., Vespertilionidae (5 spp. y Molossidae (1 sp. con un esfuerzo de 560 redes-noche. Los estimadores Chao 1 y Chao 2 indicaron que se cubrió el 77% y 42% de las especies en la zona de estudio, respectivamente. Las curvas de rango-abundancia muestran a Carollia brevicauda como la más abundante en todas las localidades; se resalta la abundancia de Vampyressa melissa en las localidades de Los Cedros y Podocarpus. Se muestra una relación inversa significativa entre la riqueza de especies y la elevación (r = -0.90, P= 0.014. En rangos de 1200-1600 m, la riqueza del SNPH (35 spp. fue mayor que en las otras Yungas presentando una mayor similitud con el Manu (Ij = 0.59; por otro lado, en rangos de 1600 – 2000 la riqueza del SNPH (14 spp. fue la segunda más alta después del Manu (21 spp., presentando una mayor similitud con San Ramón (Ij = 0.30. Los valores de complementariedad fueron altos entre el SNPH y los bosques de Yungas, entre 55-76% (1200-1600 m y entre 70-83% en (1600-2000 m. Estos resultados indican que la diversidad β de los murciélagos en las Yungas peruanas es alta; sin embargo, debemos tomar en cuenta los esfuerzos dispares entre las localidades comparadas y que se requiere más trabajo de campo en zonas de vida y elevaciones aun no exploradas del SNPH para resultados más precisos.

  5. Nuclear Ribosomal RNA Small Subunit (18S rRNA) Nucleotide Sequen Nuclear Ribosomal RNA Small Subunit (18S rRNA) Nucleotide Sequen cing and Characterization of Sailonggu(Whole Bone of Myospalax baileyi Thomas)cing%塞隆骨原动物高原鼢鼠核基因18S rRNA序列测定与分析

    Institute of Scientific and Technical Information of China (English)

    曹晖; 刘玉萍; 张绍来; 周开亚

    2001-01-01

    目的:测定仓鼠科动物高原鼢鼠Myospalax b aileyi的核rDNA基因序列,为塞隆骨正品基原检定提供分子依据。方法:采用PCR直接测序技术测定高原鼢鼠18S rRNA基因核苷酸序列并作序列特征分析。[ HT5”H〗结果:高原鼢鼠的18S rRNA序列长度为1 851 bp。根据排序比较,高原鼢鼠与2种鼠科动物间的DNA序列同源性 为72.04%~72.18%。结论:通过基因序列分析,DNA测序技术可成为 塞隆骨正品基原检定的准确有效手段。%Objective: Sequencing the nuclear ribosomal RNA small subunit (18S r RNA) gene of Myospalax baileyi (Cricetidae) to develop an ultimate and defi nitive means for origin identification of genuine Sailonggu. Methods: The total DNA wa s prepared from dried tail tissues. The nuclear 18S rRNA gene region was amplifi ed by PCR using a consensus primer set and its nucleotide sequence was determine d by PCR direct sequencing. The characteristic analysis of 18S rRNA sequences wa s generated usin software program Genetyx-SV/R Version 10.1. Results: The entire 18S rRNA gene region of M. baileyi spanned 1851 bp in length. Althou gh m ultiple alignment of sequence indicates that there are only lower homology (72.0 4%~72.18%)comparing with its two alias Mus musculus (GenBank Accession numb er X 00686)and Rattus norvegicus (M11188)(Muridae), their highly conservative dom ain i s located in 1020~1509 nt. There are many variable sites from upstream of 5'-e nd , which coud provide a novel information for molecular recognition of Sailonggu. Conclusion:DNA sequencing could be a useful and reliable tool in the origin identification of genuine Sailonggu.

  6. Видовой состав и численность мелких млекопитающих природного парка «Ергаки»

    OpenAIRE

    АЛЕХИН Е.А.

    2016-01-01

    Материал собирался в природном парке «Ергаки». Использовались стандартные методы отлова мелких млекопитающих. Сбор материала проводился в июле 2016 года. Целю работы являлось выявление различий в видовом составе и численности мелких млекопитающих в зависимости от степени антропогенной нагрузки. Задача выявить видовое разнообразие и относительную численность мелких млекопитающих. Выявлено десять видов мелких млекопитающих четырёх семейств Soricidae, Sciuridae, Muridae, Cricetidae. Видовое разн...

  7. Articoli teriologici nelle principali riviste pubblicate in Italia (1980-2003: analisi e tendenze

    Directory of Open Access Journals (Sweden)

    Luca Canova

    2004-06-01

    Full Text Available Abstract Papers on mammalogy published on the main Italian journals from 1980 to 2003: trends and analysis We analysed articles on mammalogy published from 1980 to 2003 in the main journals published in Italy: Italian Journal of Zoology (IJZ, Ethology Ecology & Evolution (EEE and Hystrix. The number of articles increased throughout the study period as well as the average number of authors. The observed frequency of paper on Carnivora Rodentia and Arctiodactyla is higher than expected on the basis of their richness, here assumed as a index of their availability for researchers. This data could be interpreted as the effect of an increased availability of funds provided by Local Administration for game management (Arctiodactyla, the attractiveness of predators and the possibility to do research at community level with small grants (Rodentia. The hypothesis is supported by a very low research effort devoted to Cetacea and Chiroptera. We observed a decreasing trend in frequency of paper concerning "traditional" approaches, a stabilisation of paper concerning mammal zoogeography and eco-ethology and a linear increase in emerging subject such as game management, conservation biology and ecotoxicology. From a quantitative point of view, Hystrix is comparable to IJZ and EEE; however, printing punctuality must be considerably improved. Riassunto È stata analizzata, sotto il profilo quali-quantitativo, la produzione di articoli teriologici pubblicata su Italian Journal of Zoology, Ethology Ecology & Evolution e Hystrix fra il 1980 e il 2003. La quantità di articoli tende ad aumentare nel tempo, al pari del numero medio di autori per articolo. La frequenza di articoli inerenti Carnivori, Roditori e Artiodattili è maggiore di quanto atteso sulla base della ricchezza di specie in Italia, assunta come indice della disponibilità di specie nella

  8. Approach to the Lower Pliocene marine-continental correlation from southern Spain. The micrommamal site of Alhaurín el Grande-1 (Málaga Basin, Betic Cordillera, Spain

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    Guerra-Merchán, A.

    2013-06-01

    Full Text Available A new micromammal site at Alhaurín el Grande (Málaga, southern Spain located above early Pliocene marine deposits allows an approach to the marine-continental correlation for this age. The early Pliocene marine filling throughout the Málaga Basin is developed in three transgressive-regressive sequences (Pl-1, Pl-2, and Pl-3 units bounded by discontinuities. At the top of the intermediate sequence Pl-2, peaty sediments have yielded fossils of Rodentia, Lagomorpha, Insectivora, and Crocodylia. The presence of Cricetus barrieri Mein & Michaux, 1970 in combination with murids, both of primitive morphology, such as Apodemus gudrunae Van de Weerd, 1976, something clearer (i.e. Occitanomys brailloni Michaux, 1969 and Stephanomys donnezani cordii Ruiz Bustos, 1986, points to an early Ruscinian age(MN14 biozone. Based on the planktonic foraminifers, the biostratigraphic data indicate that marine sediments just below the micromammal beds belong to the the MPl-2 biozone of the early Zanclean. Available paleomagnetic data from the marine sediments show that the micromammal bed must be located between the normal geomagnetic subchron C3n3n (4.89-4.80 Ma and the subchron C3n2n (4.63-4.49 Ma, limiting the age of this site to the late part of the early Zanclean.Un nuevo yacimiento de micromamíferos en Alhaurín el Grande (Málaga, Sur de España situado sobre depósitos marinos del Plioceno inferior permite una aproximación a la correlación marino-continental para esa época. El relleno sedimentario marino del Plioceno inferior en el conjunto de la cuenca de Málaga comprende tres secuencias transgresivas-regresivas (unidades Pl-1, Pl-2 y Pl-3 limitadas por discordancias. A techo de la secuencia intermedia Pl-2, sedimentos turbosos han liberado restos de Rodentia, Lagomorpha, Insectivora y Crocodylia. La presencia de Cricetus barrieri Mein & Michaux, 1970 en asociación con dos múridos, uno con morfología primitiva (Apodemus gudrunae Van de Weerd, 1976 y

  9. A survey of recent mammal collections in italy

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    Anna Maria De Marinis

    2008-02-01

    Full Text Available Abstract A survey was designed to assess the status of the collections of recent mammals in Italy through 79 questionnaires mailed to the main University institutions, municipal, provincial or regional museums and other institutions (including some private collections. We received 58 questionnaires (return rate of 73%. The minimum number of specimens in recent mammal collections in Italy is 161,268 (70% are in Italian collections and 30% in exotic ones. Most of these specimens are concentrated in a quarter of the collections. Taxidermy is the main preservation technique, above all in exotic collections (84%. 82% of the exotic collections date back to the 19th century, while specimens collected after 1950 form 91% of the Italian ones. During the 20th century the Italian collections progressively increased in number and spread through the peninsula and in Sicily. Insectivora, Rodentia, Carnivora, Lagomorpha, Artiodactyla and Primates are represented in more than 80% of the collections. Research results the primary goal both in Italian (70% and exotic (57% collections.

    Appendix
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    Riassunto Le collezioni di mammiferi attuali in Italia. Per delineare lo status delle collezioni museali di mammiferi attuali in Italia è stata condotta un’indagine mediante 79 questionari inviati a istituzioni universitarie, musei civici, provinciali e regionali ed altre istituzioni (comprese alcune collezioni private. Abbiamo ricevuto 58 questionari (73%. In Italia il numero minimo di esemplari di mammiferi attuali presenti nelle collezioni è risultato 161.268 (il 70% in collezioni italiane, il rimanente 30% in collezioni esotiche. La maggior parte degli

  10. Atropelamentos de vertebrados na Floresta Nacional de Carajás, Pará, Brasil Roadkills of vertebrates in Carajas National Forest, Para, Brazil

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    Fabiano Gumier-Costa

    2009-01-01

    Full Text Available Vários pesquisadores têm avaliado impactos de estradas. Estes podem envolver aspectos paisagísticos, degradação do solo, poluição do ar e impactos sobre a fauna, como atropelamentos. Na estrada Raimundo Mascarenhas, que atravessa a Floresta Nacional de Carajás (ca. 400 mil hectares, há intenso tráfego de veículos automotores. O objetivo deste trabalho foi testar se há diferenças entre trechos da estrada, em três escalas espaciais; se há alteração ao longo dos anos; se alguns táxons são mais freqüentemente atropelados, e se a freqüência de atropelamentos aumenta com a precipitação mensal. Analisamos a freqüência de atropelamentos de vertebrados de abril/2003 até outubro/2006 ao longo dos 25 km iniciais da estrada. Registramos 155 atropelamentos. O número de atropelamentos diminui ao longo dos anos (P=0,01, e com a distância do início da estrada (P=0,0002. Serpentes (Ophidia e gambás Didelphis marsupialis foram mais atropelados (7,5/ano, seguidos de aves, raposas Cerdocyon thous, quatis Nasua nasua, roedores (Rodentia, e não identificados (4,9/ano; cuíca Marmosops sp., tapeti Sylvilagus brasiliensis, guariba Alouatta sp., irara Eira barbara, jabuti Geochelone sp., lagartos (Lacertilia e macaco prego Cebus apella (1/ano. Não houve relação significativa entre o número mensal de atropelamentos e a precipitação mensal.Several researchers have evaluated impacts of highways. These can involve landscape aspects, soil degradation, air pollution, and impacts upon wildlife, such as roadkills. At the Raimundo Mascarenhas highway, that crosses the Carajás National Forest (ca. 400.000 ha, there is intense traffic of automotive vehicles. The aim of this work was to test if there were differences among higway sections on three spatial scales; if there was alteration along the years; if some taxa suffered more frequently roadkills; and if roadkill frequency increased with monthly precipitation. We analysed roadkill

  11. Caracterización biogeográfica de la Faja Volcánica Transmexicana y análisis de los patrones de distribución de su mastofauna Biogeographic characterization of the Transmexican Volcanic Belt and analysis of the distributional patterns of the mammal fauna

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    Niza Gámez

    2012-03-01

    Full Text Available La provincia de la Faja Volcánica Transmexicana (FVT está reconocida como centro de diversificación, endemismo y transición biogeográfica. Debido a su heterogeneidad ambiental, origen geológico complejo e intrincados patrones de distribución, aún no existe acuerdo en cuanto a su delimitación geográfica y la diferenciación ecológica y biogeográfica de su biota. Para realizar la caracterización de la provincia y de las unidades que la conforman y analizar los patrones de distribución de su mastofauna, a partir de los límites geográficos y lista de especies, se realizó un análisis espacial de su geología, altitud, clima y tipo de vegetación. Asimismo, se analizaron los patrones de riqueza y endemismo asociados con diferentes variables ambientales; esto último, a partir de modelos de nicho ecológico. Se caracteriza la FVT como una unidad biogeográfica con 2 distritos (este y oeste, donde la vegetación y la altitud son las variables que mejor explican la distribución de riqueza y endemismo de su mastofauna y la porción más relevante el bosque de pino-encino de los 2 000 a los 3 000 metros. La mayor riqueza de especies se presenta en los órdenes Rodentia y Chiroptera; 12 de los 13 géneros de mamíferos endémicos de México tienen representación en la FVT y se registran 14 especies endémicas de la provincia, en su mayoría roedores.The Transmexican Volcanic Belt (TVB is recognized as a center of diversification, endemism and biogeographic transition. Due to its environmental heterogeneity, complex geological origin and intricate distributional patterns, there is no consensus on its geographic delimitation and the ecological and biogeographic differentiation of its biota. We undertook a spatial analysis of the geology, altitude, climate and vegetation types, and the richness and endemicity patterns associated, with the aim of characterizing the province and the units within it. We also analyzed the distributional

  12. Micromamiferos andinos holocenicos del sitio arqueologico Inca Cueva 5, Ju Juy, Argentina: tafonomia, zoogeografia y reconstruccion paleoambiental

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    Ortiz, P. E.

    2002-08-01

    Full Text Available A micromammal archaeological sequence (2120 f 120 to 780 f 100 years BP from Inca Cueva 5 site (23" 05' S - 65" 27' W; 3700 m.a.s.l., Jujuy Province, Argentina was studied. The following mammalian taxa were recorded: Order Didelphimorphia, Family Didelphidae, Thylamys cf. T. pallidior; Order Rodentia, Family Muridae, Akodon cf. A. albiventer, Andinomys edax, Auliscomys sublimis, Calomys lepidus, Neotomys ebriosus, Phyllotis sp.; Family Caviidae, Cavia cf. C. tschudii, Galea musteloides; Family Abrocomidae, Abrocoma cinerea; Family Chinchillidae, Lagidium viscacia; Family Octodontidae, Octodontomys gliroides. The taphonomy indicates that the sequence is an owl pellet accumulation inside the cave. The general landscape corresponds to the oriental border of the Puna steppe, with scattered shrub and low brush vegetation. Near the site there are small tree groups of Polylepis australis as well as small streams covered with grass and ciperaceous vegetation known as «vegas». Al1 the recorded taxa at Inca Cueva 5 exist today in Puna and Prepuna environments from Jujuy and Salta Provinces and southem Bolivia, excepting Cavia cf. C. tschudii. The modem records of this species in northem Argentina and southern Bolivia come from localities with high montane bunchgrass prairies and forests of the humid Yungas phytogeographical region. The presence of this species in the sequence suggests wetter climatic conditions on this region when the archaeological site was originated. Later drier conditions, caused probably by anthropic influence in the last 500 years, produced the retraction of Cavia tschudii to the moist eastern side of the Andes and its disappeareance of the Puna areas.El sitio arqueológico Inca Cueva 5 se encuentra en la provincia de Jujuy, Argentina, en el borde oriental de la región de la Puna (23" 05' S - 65" 27' W; 3700 m s n m y está fechado entre 2120 f 120 y 780 f 100 años radiocarbónicos AP. El estudio de una pequeña muestra de

  13. Micromamíferos del Pleistoceno Medio y Pleistoceno Superior en el Valle del Jarama: yacimientos de Valdocarros y HAT (Madrid, España

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    Sesé, C.

    2011-06-01

    Full Text Available We study the micromammals from the sites of Valdocarros and HAT, located in the lithostratigraphic unit of Arganda II and IV respectively, within the Arganda Complex Terrace, in the Jarama Valley (Madrid, Spain. The micromammal associations of these sites consist of the following taxa: in Valdocarros: Erinaceomorpha: Erinaceus europaeus; Soricomorpha: Crocidura aff. russula; Rodentia: Eliomys quercinus, Castor fiber, Apodemus sp., Cricetulus (Allocricetus bursae, Arvicola aff. sapidus and Microtus brecciensis; and Lagomorpha: Oryctolagus cuniculus; and in HAT: Soricomorpha: Soricidae indet.; Rodentia: Eliomys quercinus, Apodemus sp., Arvicola aff. sapidus and Microtus cf. cabrerae; and Lagomorpha: cf. Oryctolagus sp. The micromammal assemblage of the Valdocarros site can be placed in the advanced Middle Pleistocene, but not in its end, because of the faunal association and the evolved state of Microtus brecciensis. However, in HAT, the presence of Microtus cf. cabrerae suggests that this site belongs to the Late Pleistocene. Both micromammal assemblages indicate a temperate climate and a well developed vegetation cover, consisting of some forest and also open areas, with shrub-like vegetation and also meadow and riverside vegetation.

    Se realiza el estudio de los micromamíferos del yacimiento de Valdocarros, que se localiza en la uni dad de Arganda II de la Terraza Compleja de Arganda, en el valle del Jarama (Madrid, y del yacimiento de HAT, que está en la unidad de Arganda IV. Las asociaciones de micromamíferos determinadas en este trabajo en dichos yacimientos son las siguientes: en Valdocarros: erinaceomorfos: Erinaceus europaeus; soricomorfos: Crocidura aff. russula; roedores: Eliomys quercinus, Castor fiber, Apodemus sp., Cricetulus (Allocricetus bursae, Arvicola aff. sapidus y Microtus brecciensis; y lagomorfos:

  14. Development of rapidly evolving intron markers to estimate multilocus species trees of rodents.

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    Ana Rodríguez-Prieto

    Full Text Available One of the major challenges in the analysis of closely related species, speciation and phylogeography is the identification of variable sequence markers that allow the determination of genealogical relationships in multiple genomic regions using coalescent and species tree approaches. Rodent species represent nearly half of the mammalian diversity, but so far no systematic study has been carried out to detect suitable informative markers for this group. Here, we used a bioinformatic pipeline to extract intron sequences from rodent genomes available in databases and applied a series of filters that allowed the identification of 208 introns that adequately fulfilled several criteria for these studies. The main required characteristics of the introns were that they had the maximum possible mutation rates, that they were part of single-copy genes, that they had an appropriate sequence length for amplification, and that they were flanked by exons with suitable regions for primer design. In addition, in order to determine the validity of this approach, we chose ten of these introns for primer design and tested them in a panel of eleven rodent species belonging to different representative families. We show that all these introns can be amplified in the majority of species and that, overall, 79% of the amplifications worked with minimum optimization of the annealing temperature. In addition, we confirmed for a pair of sister species the relatively high level of sequence divergence of these introns. Therefore, we provide here a set of adequate intron markers that can be applied to different species of Rodentia for their use in studies that require significant sequence variability.

  15. Evolution and function of fossoriality in the carnivora: implications for group-living

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    Michael James Noonan

    2015-10-01

    Full Text Available The societies of group-living carnivores that neither hunt nor interact cooperatively may arise due to ecological drivers and/or constraints. In this study we evaluate whether group-living may be intrinsically associated with fossoriality; a link that is well supported in other taxa, but hitherto under-evaluated in the Carnivora. We make two over-arching predictions: i that fossoriality will be associated with carnivoran sociality; and ii that this association will be most evident in those species making extended use of subterranean dens. From a meta-analysis of key behavioural, ecological, ontological, and trophic traits, we demonstrate that three quarters of carnivore species exhibit some reliance on underground dens. Congruence between life-history traits and metrics of fossoriality evidenced that: 1 there are phylogenetic, and morphological constraints on wholly fossorial life-histories; 2 fossoriality correlated positively with the extent of offspring altriciality, linked to the use of natal dens; 3 burrow use increased with latitude; and 4 insectivorous carnivores were more fossorial than predatory carnivores. Corroborating work in the Rodentia, fossorial traits associated strongly with carnivoran group-living tendencies, where species utilising subterranean natal dens are 2.5 times more likely to form groups than those that do not. Furthermore, using comparative analyses, we evidence support for an evolutionary relationship between diet, fossoriality and sociality. We propose that fossorial dens act as a safe haven, promoting fitness benefits, territorial inheritance and cooperative breeding. We conclude that, among smaller (<15kg den-using carnivores, and especially for omnivorous/ insectivorous species for which food resource dispersion is favorable, continued cohabitation at natal dens can promote cohabitation among adults; that is, philopatric benefits leading to (not necessarily cooperative spatial groups.

  16. Faster speciation and reduced extinction in the tropics contribute to the Mammalian latitudinal diversity gradient.

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    Jonathan Rolland

    2014-01-01

    Full Text Available The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha, high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha, or both (Chiroptera and Rodentia. Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the "out of the tropics" hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern.

  17. Dung beetles (Coleoptera: Scarabaeidae) attracted to dung of the largest herbivorous rodent on earth: a comparison with human feces.

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    Puker, Anderson; Correa, César M A; Korasaki, Vanesca; Ferreira, Kleyton R; Oliveira, Naiara G

    2013-12-01

    The capybara, Hydrochoerus hydrochaeris (L.) (Rodentia: Caviidae), is the largest herbivorous rodent on Earth and abundant in the Neotropical region, which can provide a stable food source of dung for dung beetle communities (Coleoptera: Scarabaeidae: Scarabaeinae). However, the use of capybara dung by dung beetles is poorly known. Here, we present data on the structure of the dung beetle community attracted to capybara dung and compare with the community attracted to human feces. Dung beetles were captured with pitfall traps baited with fresh capybara dung and human feces in pastures with exotic grass (Brachiaria spp.), patches of Brazilian savanna (Cerrado), and points of degraded riparian vegetation along the Aquidauana river in Anastácio and Aquidauana, Mato Grosso do Sul, Brazil. In traps baited with human feces, 13,809 individuals of 31 species were captured, and in those baited with capybara dung 1,027 individuals belonging to 26 species were captured. The average number of individuals and species captured by the traps baited with human feces was greater than for capybara dung in all habitats studied. Composition of the communities attracted to human feces and capybara dung formed distinct groups in all habitats. Despite the smaller number of species and individuals captured in capybara dung when compared with human feces, capybara dung was attractive to dung beetles. In Brazil, the legalization of hunting these rodents has been debated, which would potentially affect the community and consequently the ecological functions performed by dung beetles that use the feces of these animals as a resource. In addition, the knowledge of the communities associated with capybaras may be important in predicting the consequences of future management of their populations.

  18. New Insights into the Phylogeny and Gene Context Analysis of Binder of Sperm Proteins (BSPs.

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    Edith Serrano

    Full Text Available Seminal plasma (SP proteins support the survival of spermatozoa acting not only at the plasma membrane but also by inhibition of capacitation, resulting in higher fertilizing ability. Among SP proteins, BSP (binder of sperm proteins are the most studied, since they may be useful for the improvement of semen diluents, storage and subsequent fertilization results. However, an updated and detailed phylogenetic analysis of the BSP protein superfamily has not been carried out with all the sequences described in the main databases. The update view shows for the first time an equally distributed number of sequences between the three families: BSP, and their homologs 1 (BSPH1 and 2 (BSPH2. The BSP family is divided in four subfamilies, BSP1 subfamily being the predominant, followed by subfamilies BSP3, BSP5 and BSP2. BSPH proteins were found among placental mammals (Eutheria belonging to the orders Proboscidea, Primates, Lagomorpha, Rodentia, Chiroptera, Perissodactyla and Cetartiodactyla. However, BSPH2 proteins were also found in the Scandentia order and Metatheria clade. This phylogenetic analysis, when combined with a gene context analysis, showed a completely new evolutionary scenario for the BSP superfamily of proteins with three defined different gene patterns, one for BSPs, one for BSPH1/BSPH2/ELSPBP1 and another one for BSPH1/BSPH2 without ELSPBP1. In addition, the study has permitted to define concise conserved blocks for each family (BSP, BSPH1 and BSPH2, which could be used for a more reliable assignment for the incoming sequences, for data curation of current databases, and for cloning new BSPs, as the one described in this paper, ram seminal vesicle 20 kDa protein (RSVP20, Ovis aries BSP5b.

  19. Mammalian Herbivores in the Boreal Forests: Their Numerical Fluctuations and Use by Man

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    Kjell Danell

    1998-12-01

    Full Text Available Within the boreal zone, there are about 50 native mammalian herbivore species that belong to the orders Artiodactyla, Rodentia, and Lagomorpha. Of these species, 31 occur in the Nearctic and 24 in the Palaearctic. Only six species occur in both regions. Species of the family Cervidae have probably been, and still are, the most important group for man, as they provide both meat and hides. Pelts from squirrels, muskrats, and hares were commercially harvested at the beginning of the century, but have less value today. The semi-domestic reindeer in the Palaearctic produces meat and hides on a commercial basis. It is also used for milking, to a limited extent, as is the semi-domestic moose in Russia. The Siberian musk deer is used for its musk and is raised in captivity in China. All species heavier than 1 kg are utilized by man, those with a body mass in the range 1 kg - 1 hg are sometimes used, and species lighter than 1 hg are rarely used. Here, we review the numerical fluctuations in terms of periodicity and amplitude, based on an extensive data set found in the literature, especially from the former Soviet Union. Current understanding of the underlying factors behind the population fluctuations is briefly reviewed. Management and conservation aspects of the mammalian herbivores in the boreal zone are also discussed. We conclude that there is a challenge to manage the forests for the mammalian herbivores, but there is also a challenge to manage the populations of mammalian herbivores for the forests.

  20. Small mammal communities of the "Monte Rufeno" Natural Reserve (Latium, Italy: data from Barn Owl Tyto alba pellets / I popolamenti di micromammiferi della Riserva Naturale "Monte Rufeno" (Lazio: dati da borre di barbagianni Tyto alba

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    Gaetano Aloise

    1990-07-01

    Full Text Available Abstract A high number of preys (7,147 specimens from barn owl pellets were collected in 15 sites of Monte Rufeno Natural Reserve. The 97.42% were small mammals, belonging to at least 6 species of Insectivora, 3 species of Chiroptera and 8 of Rodentia. The use of adequate indexes showed as expected, a high faunistic and biocenotic affinity among all sites of the Natural Reserve. Moreover, the values of trophic leve1 are analogous to the mean values found by others in the province of Rome. The biotic diversity is low and this result can be explained with predation of the barn owls over the most anthropizated areas out of the Natural Reserve. Faunistic and biocenotic indexes were utilized to compare the study area with other localities of Centra1 Italy characterized by typical mediterranean or temperate bioclimate. In one of the sites studied (Podernovo, seasonal changes of predation were analyzed. Riassunto In 15 siti posti all'interno della Riserva Naturale "Monte Rufeno" sono state raccolte numerose borre di Barbagianni Tyto alba in cui sono state rinvenute 7147 prede di cui il 97.42% costituito da micromammiferi. Alcuni indici ecologici (affinità biocenotica e faunistica, diversità biotica, termoxerofilia, antropizzazione, livello trofico sono stati applicati ai dati relativi ai micromammiferi terragnoli. Un confronto faunistico e biocenotico è stato effettuato tra i siti del comprensorio ed alcune località dell'Italia centrale caratteristiche di ambienti a bioclima mediterraneo o temperato. In uno dei siti studiati (Podernovo è stato possibile analizzare l'andamento stagionale della predazione.

  1. A survey of hemoparasite infections in free-ranging mammals and reptiles in French Guiana.

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    de Thoisy, B; Michel, J C; Vogel, I; Vié, J C

    2000-10-01

    Blood smears of 1,353 free-ranging mammals (35 species) and 112 reptiles (31 species) from French Guiana were examined for hemoparasites. Parasites from 3 major groups were recorded: Apicomplexa (including hemogregarines, piroplasms, and Plasmodium spp.), Trypanosomatidae, and Filaroidea. Fifty percent of the individuals (86% of the species) were infected by parasites from at least 1 group. Hemogregarines, identified as Hepatozoon sp., infected numerous snakes with high prevalences (30-100%); infection is reported for the first time in 5 host genera of snakes: Clelia, Oxybelis, Pseustes, Rhinobotryum, and Bothriopsis. Infections were also observed in 4 marsupial species and 1 rodent. Hepatozoon spp. recorded in Didelphis albiventris (Marsupialia) and Coendou prehensilis (Rodentia) may be new species. Plasmodium sp. were observed in 2 snake species, Dipsas indica (Colubridae) and Bothrops atrox (Viperidae). Plasmodium brasilianum was recorded in all 5 primate species examined. Piroplasms were observed in all mammal orders except primates. Large terrestrial rodents were the main hosts of members of the Babesidae; 42% of Myoprocta acouchy, 36% of Dasyprocta agouti, and 44% of Agouti paca were infected. Trypanosomes were common in mammals and were recorded in 70% of the examined genera. Trypanosoma cruzi-like infections were reported in 21 mammal species, including sloths, rodents, carnivores, and primates. Microfilariae were also widespread, with higher prevalences in sloths, anteaters, and porcupines (>40% of the individuals infected) and in tamarins (95% infected). This survey highlights some potential anthropozoonotic risks due to the recent further evidence of Plasmodium brasilianum and P. malariae as a single species and to the increased diversity of hosts for Trypanosoma cruzi.

  2. A First Generation Comparative Chromosome Map between Guinea Pig (Cavia porcellus) and Humans.

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    Romanenko, Svetlana A; Perelman, Polina L; Trifonov, Vladimir A; Serdyukova, Natalia A; Li, Tangliang; Fu, Beiyuan; O'Brien, Patricia C M; Ng, Bee L; Nie, Wenhui; Liehr, Thomas; Stanyon, Roscoe; Graphodatsky, Alexander S; Yang, Fengtang

    2015-01-01

    The domesticated guinea pig, Cavia porcellus (Hystricomorpha, Rodentia), is an important laboratory species and a model for a number of human diseases. Nevertheless, genomic tools for this species are lacking; even its karyotype is poorly characterized. The guinea pig belongs to Hystricomorpha, a widespread and important group of rodents; so far the chromosomes of guinea pigs have not been compared with that of other hystricomorph species or with any other mammals. We generated full sets of chromosome-specific painting probes for the guinea pig by flow sorting and microdissection, and for the first time, mapped the chromosomal homologies between guinea pig and human by reciprocal chromosome painting. Our data demonstrate that the guinea pig karyotype has undergone extensive rearrangements: 78 synteny-conserved human autosomal segments were delimited in the guinea pig genome. The high rate of genome evolution in the guinea pig may explain why the HSA7/16 and HSA16/19 associations presumed ancestral for eutherians and the three syntenic associations (HSA1/10, 3/19, and 9/11) considered ancestral for rodents were not found in C. porcellus. The comparative chromosome map presented here is a starting point for further development of physical and genetic maps of the guinea pig as well as an aid for genome assembly assignment to specific chromosomes. Furthermore, the comparative mapping will allow a transfer of gene map data from other species. The probes developed here provide a genomic toolkit, which will make the guinea pig a key species to unravel the evolutionary biology of the Hystricomorph rodents.

  3. Evolution of C, D and S-type cystatins in mammals: an extensive gene duplication in primates.

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    de Sousa-Pereira, Patrícia; Abrantes, Joana; Pinheiro, Ana; Colaço, Bruno; Vitorino, Rui; Esteves, Pedro J

    2014-01-01

    Cystatins are a family of inhibitors of cysteine peptidases that comprises the salivary cystatins (D and S-type cystatins) and cystatin C. These cystatins are encoded by a multigene family (CST3, CST5, CST4, CST1 and CST2) organized in tandem in the human genome. Their presence and functional importance in human saliva has been reported, however the distribution of these proteins in other mammals is still unclear. Here, we performed a proteomic analysis of the saliva of several mammals and studied the evolution of this multigene family. The proteomic analysis detected S-type cystatins (S, SA, and SN) in human saliva and cystatin D in rat saliva. The evolutionary analysis showed that the cystatin C encoding gene is present in species of the most representative mammalian groups, i.e. Artiodactyla, Rodentia, Lagomorpha, Carnivora and Primates. On the other hand, D and S-type cystatins are mainly retrieved from Primates, and especially the evolution of S-type cystatins seems to be a dynamic process as seen in Pongo abelii genome where several copies of CST1-like gene (cystatin SN) were found. In Rodents, a group of cystatins previously identified as D and S has also evolved. Despite the high divergence of the amino acid sequence, their position in the phylogenetic tree and their genome organization suggests a common origin with those of the Primates. These results suggest that the D and S type cystatins have emerged before the mammalian radiation and were retained only in Primates and Rodents. Although the mechanisms driving the evolution of cystatins are unknown, it seems to be a dynamic process with several gene duplications evolving according to the birth-and-death model of evolution. The factors that led to the appearance of a group of saliva-specific cystatins in Primates and its rapid evolution remain undetermined, but may be associated with an adaptive advantage.

  4. Next-generation sequencing for rodent barcoding: species identification from fresh, degraded and environmental samples.

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    Galan, Maxime; Pagès, Marie; Cosson, Jean-François

    2012-01-01

    Rodentia is the most diverse order among mammals, with more than 2,000 species currently described. Most of the time, species assignation is so difficult based on morphological data solely that identifying rodents at the specific level corresponds to a real challenge. In this study, we compared the applicability of 100 bp mini-barcodes from cytochrome b and cytochrome c oxidase 1 genes to enable rodent species identification. Based on GenBank sequence datasets of 115 rodent species, a 136 bp fragment of cytochrome b was selected as the most discriminatory mini-barcode, and rodent universal primers surrounding this fragment were designed. The efficacy of this new molecular tool was assessed on 946 samples including rodent tissues, feces, museum samples and feces/pellets from predators known to ingest rodents. Utilizing next-generation sequencing technologies able to sequence mixes of DNA, 1,140 amplicons were tagged, multiplexed and sequenced together in one single 454 GS-FLX run. Our method was initially validated on a reference sample set including 265 clearly identified rodent tissues, corresponding to 103 different species. Following validation, 85.6% of 555 rodent samples from Europe, Asia and Africa whose species identity was unknown were able to be identified using the BLASTN program and GenBank reference sequences. In addition, our method proved effective even on degraded rodent DNA samples: 91.8% and 75.9% of samples from feces and museum specimens respectively were correctly identified. Finally, we succeeded in determining the diet of 66.7% of the investigated carnivores from their feces and 81.8% of owls from their pellets. Non-rodent species were also identified, suggesting that our method is sensitive enough to investigate complete predator diets. This study demonstrates how this molecular identification method combined with high-throughput sequencing can open new realms of possibilities in achieving fast, accurate and inexpensive species identification.

  5. Expensive brains: ‘brainy’ rodents have higher metabolic rate

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    Raúl eSobrero

    2011-07-01

    Full Text Available Brains are the centers of the nervous system of animals, controlling the organ systems of the body and coordinating responses to changes in the ecological and social environment. The evolution traits that correlate with cognitive ability, such as relative brain size is thus of broad interest. Brain mass relative to body mass varies among mammals, and diverse factors have been proposed to explain this variation. A recent study provided evidence that energetics play an important role in brain evolution (Isler and van Schaik, 2006. Using composite phylogenies and data drawn from multiple sources, these authors showed that basal metabolic rate (BMR correlates with brain mass across mammals. However, no such relationship was found within rodents. Here we re-examined the relationship between BMR and brain mass within Rodentia using a novel species-level phylogeny. Our results are sensitive to parameter evaluation; in particular how species mass is estimated. We detect no pattern when applying an approach used by previous studies, where each species body mass is represented by two different numbers, one being the individual that happened to be used for BMR estimates of that species. However, this approach may compromise the analysis. When using a single value of body mass for each species, whether representing a single individual, or available species mean, our findings provide evidence that brain mass (independent of body mass and BMR are correlated. These findings are thus consistent with the hypothesis that large brains evolve when the payoff for increased brain mass is greater than the energetic cost they incur.

  6. Spatial and temporal activity patterns of the free-living giant mole-rat (Fukomys mechowii, the largest social bathyergid.

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    Matěj Lövy

    Full Text Available Despite the considerable attention devoted to the biology of social species of African mole-rats (Bathyergidae, Rodentia, knowledge is lacking about their behaviour under natural conditions. We studied activity of the largest social bathyergid, the giant mole-rat Fukomys mechowii, in its natural habitat in Zambia using radio-telemetry. We radio-tracked six individuals during three continuous 72-h sessions. Five of these individuals, including a breeding male, belonged to a single family group; the remaining female was probably a solitary disperser. The non-breeders of the family were active (i.e. outside the nest 5.8 hours per 24h-day with the activity split into 6.5 short bouts. The activity was more concentrated in the night hours, when the animals also travelled longer distances from the nest. The breeding male spent only 3.2 hours per day outside the nest, utilizing less than 20% of the whole family home range. The dispersing female displayed a much different activity pattern than the family members. Her 8.0 hours of outside-nest activity per day were split into 4.6 bouts which were twice as long as in the family non-breeders. Her activity peak in the late afternoon coincided with the temperature maximum in the depth of 10 cm (roughly the depth of the foraging tunnels. Our results suggest that the breeding individuals (at least males contribute very little to the work of the family group. Nevertheless, the amount of an individual's activity and its daily pattern are probably flexible in this species and can be modified in response to actual environmental and social conditions.

  7. Micromammals in the diet of the Long-eared Owl (Asio otus at the W.W.F.'s Oasi San Giuliano (Matera, South Italy

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    Francesco Cecere

    2000-09-01

    Full Text Available Abstract The presence of small mammals in the winter diet of a dormitory made up of 5 specimens living at the WWF's Oasi San Giuliano (province of Matera is analysed in the following study. The data confirm the presence of small mammals, Microtinae in particular, as a main prey of the Long-eared Owl. 1921 prey-individuals totalling 37695 grams in biomass were found. Rodentia are dominant (86.93% of the biomass; Microtus savii is of particular importance and represents 61.06% of the total biomass and was found in 60.42% of the pellets found. The second most frequently hunted species is the Apodemus sp.: 24.06% of the biomass, 37.08% of the frequency. The other mammals preyed on (Suncus etruscus, Crocidura sp., Pipistrellus sp., Vespertilius sp., Rattus sp., Moscardinus avellanarius are of little importance: 1.27% of the biomass. The owls preyed upon 9 of the 11 species of mammals present (the Talpa sp. and the Mus domesticus are absent. Affinity among different periods, estimated through Sorensen's Index, was found to be medium-high (0.67-0.72. The data analysis confirms the stenophagy of the Long-eared Owl, in this area that is characterised by extensive cereal cultivation and few shrubs and trees. In comparison with other Italian localities, a greater number of preyed species was recorded (8 mammals, 9 birds, 1 insect. Roost owls preyed mainly upon Chiroptera (0.36% compared with 0.1-0.2. Myotis capaccinii and Pipistrellus savii were also found in the diet of the Long-eared Owl for the first time in Italy.

  8. Occurrence of ectoparasitic arthropods associated with rodents in Hail region northern Saudi Arabia.

    Science.gov (United States)

    Asiry, Khalid A; Fetoh, Badr El-Sabah A

    2014-09-01

    Ectoparasitic arthropods are a diverse element of the Saudi fauna. Due to this, a survey of ectoparasites associated with rodents was conducted as a preliminary study in five districts of Hail region of northern Saudi Arabia for the first time. Ectoparasites extracted from 750 rodents were sampled and identified by recording their frequency of appearance. Results revealed that 1,287 ectoparasites infested 316 of the captured rodent hosts. These ectoparasites parasitized on four species of rodents including three species of rats Rattus rattus rattus, Rattus rattus frugivorus, and Rattus rattus alexandrinus and one species of mouse Acomys dimidiatus (Rodentia: Muridae). The ectoparasites belong to four different groups: ticks, fleas, lice, and mites. Ticks were the highest in the number, while fleas were the lowest among all the extracted ectoparasite groups. The collected ectoparasitic arthropods consisted of seven species. Ticks were of two species: Rhipicephalus turanicus and Rhipicephalus sanguineus (Acari: Ixodidae), fleas were of two species: Xenopsylla cheopis and Xenopsyllus conformis mycerini (Siphonaptera: Pulicidae), lice was a single species: Polyplax serrata (Anoplura: Hoplopleuridae), and mites were of two species: Laelaps nuttali and Laelaps echidninus (Mesostigmata: Laelapidae). The findings of the study showed that the intensity of infestation was varied between rodent host sexes, wherein females had the highest rate of parasitic infestation, and the parasitic index of appearance was very high for one group of parasites (i.e., ticks). The parasitic prevalence was 42.13 % on rodents, and mites were the most prevalent parasite species. Overall, this study was carried out to establish baseline data for ectoparasite-infested rodents in Hail region, Saudi Arabia, and may help for appropriate planning to control zoonotic diseases in this area.

  9. Diversity of Sucking Lice on Small Mammals in the Surrounding Areas of Erhai Lake in Yunnan, China%中国云南洱海周边小兽体表吸虱多样性

    Institute of Scientific and Technical Information of China (English)

    董文鸽; 郭宪国; 门兴元; 钱体军; 吴滇

    2009-01-01

    An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004.From investigation sites, 3 303 small mammal hosts were captured and identified into 7families, 15 genera and 21 species in 4 orders (Rodentia, Insectivora, Scandentia and Carnivora), while 14 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura. The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain.The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity,abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking li ce and their corresponding hosts. A certain species of hosts usually have theirfixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mam mal host in different oriented areas of Erhai Lake are homologous. The results stronglysuggest a close relationship of co-evolution between sucking lice and their hosts.

  10. Complete mitochondrial genome of the Eurasian flying squirrel Pteromys volans (Sciuromorpha, Sciuridae) and revision of rodent phylogeny.

    Science.gov (United States)

    Ryu, Shi Hyun; Kwak, Min Jung; Hwang, Ui Wook

    2013-02-01

    In this study, the complete mitochondrial genome of the Eurasian flying squirrel Pteromys volans (Rodentia, Sciuromorpha, Sciuridae) was sequenced and characterized in detail. The entire mitochondrial genome of P. volans consisted of 16,513 bp and contained 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions. Its gene arrangement pattern was consistent with the mammalian ground pattern. The overall base composition and AT contents were similar to those of other rodent mitochondrial genomes. The light-strand origin generally identified between tRNA ( Asn ) and tRNA ( Cys ) consisted of a secondary structure with an 11-bp stem and an 11-bp loop. The large control region was constructed of three characteristic domains, ETAS, CD, and CSB without any repeat sequences. Each domain contained ETAS1, subsequences A, B, and C, and CSB1, respectively. In order to examine phylogenetic contentious issues of the monophyly of rodents and phylogenetic relationships among five rodent suborders, here, phylogenetic analyses based on nucleotide sequence data of the 35 rodent and 3 lagomorph mitochondrial genomes were performed using the Bayesian inference and maximum likelihood method. The result strongly supported the rodent monophyly with high node confidence values (BP 100 % in ML and BPP 1.00 in BI) and also monophylies of four rodent suborders (BP 85-100 % in ML and BPP 1.00 in BI), except for Anomalumorpha in which only one species was examined here. Also, phylogenetic relationships among the five rodent suborders were suggested and discussed in detail.

  11. Cholinergic urethral brush cells are widespread throughout placental mammals.

    Science.gov (United States)

    Deckmann, Klaus; Krasteva-Christ, Gabriela; Rafiq, Amir; Herden, Christine; Wichmann, Judy; Knauf, Sascha; Nassenstein, Christina; Grevelding, Christoph G; Dorresteijn, Adriaan; Chubanov, Vladimir; Gudermann, Thomas; Bschleipfer, Thomas; Kummer, Wolfgang

    2015-11-01

    We previously identified a population of cholinergic epithelial cells in murine, human and rat urethrae that exhibits a structural marker of brush cells (villin) and expresses components of the canonical taste transduction signaling cascade (α-gustducin, phospholipase Cβ2 (PLCβ2), transient receptor potential cation channel melanostatin 5 (TRPM5)). These cells serve as sentinels, monitoring the chemical composition of the luminal content for potentially hazardous compounds such as bacteria, and initiate protective reflexes counteracting further ingression. In order to elucidate cross-species conservation of the urethral chemosensory pathway we investigated the occurrence and molecular make-up of urethral brush cells in placental mammals. We screened 11 additional species, at least one in each of the five mammalian taxonomic units primates, carnivora, perissodactyla, artiodactyla and rodentia, for immunohistochemical labeling of the acetylcholine synthesizing enzyme, choline acetyltransferase (ChAT), villin, and taste cascade components (α-gustducin, PLCβ2, TRPM5). Corresponding to findings in previously investigated species, urethral epithelial cells with brush cell shape were immunolabeled in all 11 mammals. In 8 species, immunoreactivities against all marker proteins and ChAT were observed, and double-labeling immunofluorescence confirmed the cholinergic nature of villin-positive and chemosensory (TRPM5-positive) cells. In cat and horse, these cells were not labeled by the ChAT antiserum used in this study, and unspecific reactions of the secondary antiserum precluded conclusions about ChAT-expression in the bovine epithelium. These data indicate that urethral brush cells are widespread throughout the mammalian kingdom and evolved not later than about 64.5millionyears ago.

  12. Light perception in two strictly subterranean rodents: life in the dark or blue?

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    Ondrej Kott

    Full Text Available BACKGROUND: The African mole-rats (Bathyergidae, Rodentia are strictly subterranean, congenitally microphthalmic rodents that are hardly ever exposed to environmental light. Because of the lack of an overt behavioural reaction to light, they have long been considered to be blind. However, recent anatomical studies have suggested retention of basic visual capabilities. In this study, we employed behavioural tests to find out if two mole-rat species are able to discriminate between light and dark, if they are able to discriminate colours and, finally, if the presence of light in burrows provokes plugging behaviour, which is assumed to have a primarily anti-predatory function. METHODOLOGY/PRINCIPAL FINDING: We used a binary choice test to show that the silvery mole-rat Heliophobius argenteocinereus and the giant mole-rat Fukomys mechowii exhibit a clear photoavoidance response to full-spectrum ("white", blue and green-yellow light, but no significant reaction to ultraviolet or red light during nest building. The mole-rats thus retain dark/light discrimination capabilities and a capacity to perceive short to medium-wavelength light in the photopic range of intensities. These findings further suggest that the mole-rat S opsin has its absorption maximum in the violet/blue part of the spectrum. The assay did not yield conclusive evidence regarding colour discrimination. To test the putative role of vision in bathyergid anti-predatory behaviour, we examined the reaction of mole-rats to the incidence of light in an artificial burrow system. The presence of light in the burrow effectively induced plugging of the illuminated tunnel. CONCLUSION/SIGNIFICANCE: Our findings suggest that the photopic vision is conserved and that low acuity residual vision plays an important role in predator avoidance and tunnel maintenance in the African mole-rats.

  13. Distribution of gamasid mites on small mammals in Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    LI-PU LUO; XIAN-GUO GUO; TI-JUN QIAN; DIAN WU; XING-YUAN MEN; WEN-GE DONG

    2007-01-01

    An investigation of gamasid mites on the body surface of small mammals wascarried outin Yunnan Province of China from 1990 to 2004. The small mammal hosts werecaptured from 25 counties which represent five geographical subregions, namely MiddleSubregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, EasternPlateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun-tainous Subregion of Yunnan. The captured 10803 small mammal hosts belong to ninefamilies, 29 genera and 52 species in four orders (Rodentia, Insectivora, Scandentia andLagomorpha). A total of 68 571 gamasid mites were collected from the body surface of thecaptured small mammal hosts and all the gamasid mites were identified to 10 families, 33genera and 112 species. This paper lists all the mite species, together with their taxonomicposition (genera and families) and their corresponding hosts. Much more mite species werefound in the Middle Subregion of Hengduan Mountains than in other geographical subregions.The total individuals of mites and small mammals in the Middle Subregion of HengduanMountains are also the most plentiful in the five geographical subregions. Three dominantmite species and three dominant small mammal hosts were determined as the dominant. species in the investigated areas of Yunnan Province. The dominant hosts are Rattusflavipectus (which accounts for 34.85 % of the total individuals), Apodemus chevrieri (13.43 %)and Rattus norvegicus (10.40%) while the dominant gamasid mite species are Laelapsnuttalli (Hirst, 1915) (27.84%), Laelaps echidninus (Berlese, 1887) (18.38%) and Laelapsguizhouensis (Gu et Wang, 1981) (14.79%). The results showed the high species diversityof gamasid mites in Yunnan Province and the uneven distribution feature in differentsubregions.

  14. Preliminary inventory of mammals from Yurubí National Park, Yaracuy, Venezuela with some comments on their natural history.

    Science.gov (United States)

    García, Franger J; Delgado-Jaramillo, Mariana; Machado, Marjorie; Aular, Luis

    2012-03-01

    In Venezuela, mammals represent an important group of wildlife with high anthropogenic pressures that threaten their permanence. Focused on the need to generate baseline information that allows us to contribute to document and conserve the richness of local wildlife, we conducted a mammalogical inventory in Yurubí National Park, located in Yaracuy State in Venezuela. We carried out fieldworks in three selected vegetation types: an evergreen forest at 197m, a semi-deciduous forest ranging between 100-230m, and a cloud forest at 1 446m. We used Victor, Sherman, Havahart and pitfall traps for the capture of small non-volant mammals and mist nets for bats. In addition, we carried out interviews with local residents and direct-indirect observations for medium-large sized mammals. At least 79 species inhabit the area, representing 28% of the species recorded for the North side of the country. Chiroptera (39 spp.), Carnivora (13 spp.) and Rodentia (9 spp.) were the orders with the highest richness, as expected for the Neotropics. The evergreen forest had the greatest species richness (n=68), with a sampling effort of 128 net-hours, 32 bucket-days, 16 hours of observations, and three persons interviewed, followed by cloud forest (n=45) with 324 net-hours, 790 traps-night, 77 bucket-days, 10 hours of observations, and one person interviewed. The lowest richness value was in the semi-deciduous forest (n=41), with 591 traps-night, 15 net-hours, 10 hours of observations and three persons interviewed. Data and observations obtained in this inventory (e.g., endemism, species known as "surrogate species" threatened in Venezuela) give an important role at the Yurubí National Park in the maintenance and conservation of local ecosystems and wildlife, threatened by human pressures in the Cordillera de la Costa.

  15. Threat diversity will erode mammalian phylogenetic diversity in the near future.

    Directory of Open Access Journals (Sweden)

    Clémentine M A Jono

    Full Text Available To reduce the accelerating rate of phylogenetic diversity loss, many studies have searched for mechanisms that could explain why certain species are at risk, whereas others are not. In particular, it has been demonstrated that species might be affected by both extrinsic threat factors as well as intrinsic biological traits that could render a species more sensitive to extinction; here, we focus on extrinsic factors. Recently, the International Union for Conservation of Nature developed a new classification of threat types, including climate change, urbanization, pollution, agriculture and aquaculture, and harvesting/hunting. We have used this new classification to analyze two main factors that could explain the expected future loss of mammalian phylogenetic diversity: 1. differences in the type of threats that affect mammals and 2. differences in the number of major threats that accumulate for a single species. Our results showed that Cetartiodactyla, Diprotodontia, Monotremata, Perissodactyla, Primates, and Proboscidea could lose a high proportion of their current phylogenetic diversity in the coming decades. In contrast, Chiroptera, Didelphimorphia, and Rodentia could lose less phylogenetic diversity than expected if extinctions were random. Some mammalian clades, including Marsupiala, Chiroptera, and a subclade of Primates, are affected by particular threat types, most likely due solely to their geographic locations and associations with particular habitats. However, regardless of the geography, habitat, and taxon considered, it is not the threat type, but the threat diversity that determines the extinction risk for species and clades. Thus, some mammals might be randomly located in areas subjected to a large diversity of threats; they might also accumulate detrimental traits that render them sensitive to different threats, which is a characteristic that could be associated with large body size. Any action reducing threat diversity is

  16. New Insights into the Phylogeny and Gene Context Analysis of Binder of Sperm Proteins (BSPs)

    Science.gov (United States)

    Arruga, Diana; Pérez-Pé, Rosaura; Sánchez-Ferrer, Álvaro; Muiño-Blanco, Teresa; Cebrián-Pérez, José A.

    2015-01-01

    Seminal plasma (SP) proteins support the survival of spermatozoa acting not only at the plasma membrane but also by inhibition of capacitation, resulting in higher fertilizing ability. Among SP proteins, BSP (binder of sperm) proteins are the most studied, since they may be useful for the improvement of semen diluents, storage and subsequent fertilization results. However, an updated and detailed phylogenetic analysis of the BSP protein superfamily has not been carried out with all the sequences described in the main databases. The update view shows for the first time an equally distributed number of sequences between the three families: BSP, and their homologs 1 (BSPH1) and 2 (BSPH2). The BSP family is divided in four subfamilies, BSP1 subfamily being the predominant, followed by subfamilies BSP3, BSP5 and BSP2. BSPH proteins were found among placental mammals (Eutheria) belonging to the orders Proboscidea, Primates, Lagomorpha, Rodentia, Chiroptera, Perissodactyla and Cetartiodactyla. However, BSPH2 proteins were also found in the Scandentia order and Metatheria clade. This phylogenetic analysis, when combined with a gene context analysis, showed a completely new evolutionary scenario for the BSP superfamily of proteins with three defined different gene patterns, one for BSPs, one for BSPH1/BSPH2/ELSPBP1 and another one for BSPH1/BSPH2 without ELSPBP1. In addition, the study has permitted to define concise conserved blocks for each family (BSP, BSPH1 and BSPH2), which could be used for a more reliable assignment for the incoming sequences, for data curation of current databases, and for cloning new BSPs, as the one described in this paper, ram seminal vesicle 20 kDa protein (RSVP20, Ovis aries BSP5b). PMID:26333091

  17. Historical biogeography of the strepsirhine primates of Madagascar.

    Science.gov (United States)

    Tattersall, Ian

    2006-01-01

    Lying some 400 km off the coast of southeastern Africa, Madagascar is the world's largest oceanic island. It has been in roughly the same position relative to its parent continent for 120 million years, and as a consequence its mammal fauna is unusual in composition, with a low number of major taxa but a high diversity at lower taxonomic levels. Among Madagascar's native terrestrial mammals, only the orders Primates, Rodentia, Carnivora and Insectivora are represented (plus, until recently, the enigmatic and endemic Bibymalagasia, and Artiodactyla in the form of semiaquatic pygmy hippopotamuses). This reflects the fact that terrestrial mammals are notoriously poor over-water dispersers; yet at the same time the ancestors of all of Madagascar's mammals had to have crossed a wide oceanic barrier to get to the island at various points during the Tertiary. Here I examine the palaeogeographic evidence for potential land bridge or 'stepping-stone' connections with adjacent continents from the Mesozoic through the Cenozoic, and review the fossil records and phylogenies of each of Madagascar's mammalian groups in an attempt to estimate the minimum number of crossings necessary to produce the island's current faunal composition. Probable monophyletic origins for each major group, and thus a smaller rather than a larger number of crossings of the Mozambique Channel, imply that this water barrier has acted as a powerful filter; so powerful that it is unclear whether any crossings would have been possible without some form of subaerial connection, however ephemeral, at least from time to time during the Tertiary. Clarification of how Madagascar's terrestrial mammal fauna may have originated is thus as likely to emerge from the geology of the seafloor surrounding the island as it is to come from the fossil record or from the internal and external relationships of its various components.

  18. Ecological Niche Modeling of main reservoir hosts of zoonotic cutaneous leishmaniasis in Iran.

    Science.gov (United States)

    Gholamrezaei, Mostafa; Mohebali, Mehdi; Hanafi-Bojd, Ahmad Ali; Sedaghat, Mohammad Mehdi; Shirzadi, Mohammad Reza

    2016-08-01

    Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, is a common zoonotic vector-borne disease in Iran. Close contact with infected reservoir hosts increases the probability of transmission of Leishmania parasite infections to susceptible humans. Four gerbil species (Rodentia: Gerbillidae) serve as the main reservoir hosts for ZCL in different endemic foci of Iran. These species include Rhombomys opimus, Meriones libycus, Meriones hurrianae and Tatera indica; while notable infection has been reported in Nesokia indica as well. The purpose of this study is to model the distribution of these reservoirs to identify the risk areas of ZCL. A data bank was developed including all published data during the period of 1970-2015. Maximum entropy model was used to find the most appropriate ecological niches for each species. The areas under curve obtained were 0.961, 0.927, 0.922, 0.997 and 0.899, instead of 1, for training test in R. opimus, M. libycus, T. indica, M. hurrianae and N. indica, respectively. The environmental variable with the highest gain when used in isolation was slope for R. opimus and N. indica, annual mean temperature for M. libycus, and seasonal precipitation for T. indica and M. hurrianae. Summation of presence probabilities for three main species, i.e., R. opimus, M. libycus and T. indica revealed favorable ecological niches in wide areas of 16 provinces. This is the first study to predict the distribution of ZCL reservoir hosts in Iran. Climatology and topography variables had high contributions toward the prediction of potential distribution of the main reservoir species; therefore, as climate changes, the models should be updated periodically with novel data, and the results should be used in disease-monitoring programs.

  19. Efecto del corredor vial Buga-Buenaventura, ubicado en la reserva natural bosque de Yotoco (Valle del Cauca, Colombia en la comunidad de mamíferos y fundamento para una propuesta de corredores artificiales

    Directory of Open Access Journals (Sweden)

    López Meneses Wendy Francy

    2006-12-01

    Full Text Available A través de algunas de las metodologías de campo estándares para el muestreo de pequeños mamíferos
    terrestres, voladores, medianos y grandes se determinaron los sitios de paso más frecuentes y las tendencias
    de movilidad de la fauna, por la carretera Buga-Buenaventura que pasa a través de la Reserva Natural Bosque de Yotoco, Valle del Cauca. La caracterización topográfica y fisionómica de la vegetación mostró un mosaico de diez ambientes asociados a la carretera los cuales se asociaron con los puntos captura, de observación y de atropellamiento. Se encontró que individuos de Melanomys caliginosus, Oryzomys talamancae, Rhipidomys mastacalis y Marmosa robinsoni, recapturados en más de tres ocasiones, tienden a moverse paralelamente a la carretera, sin ninguna evidencia de cruce. A pesar de que no hubo recapturas de individuos de las especies de mamíferos voladores Anoura cauddifer, Artibeus jamaicensis, Artibeus sp., Carollia brevicauda, Desmodus rotundus, Glosophaga Soricina, Sturnira luisi y Myotis riparius se puede afirmar que cruzan indiferentemente la carretera, viven en los desagues bajo esta y algunos forrajean en el borde. Particularmente Myotis riparius se ve atraída por los insectos que llegan por efecto de la luz vehicular. Los mamíferos medianos y grandes Cebus capucinus, Alouatta seniculus, Potos flavus, Aotus sp., Bradypus variegatus y Choloepus hoffmanni, forrajean en el día y en la noche cerca del borde, algunos individuos de Cebus capucinus y Alouatta seniculus fueron vistos cruzando la carretera del fragmento pequeño al grande. La fragmentación de hábitat ocasionada por dicha carretera es evidente y está ocasionando un aislamiento total en las especies de pequeños mamíferos y genera peligro de atropellamiento para algunas especies de murciélagos y monos que la cruzan. Ambientes hostiles como helechales, pastizales, cañaduzales y deslizamientos penetran cada vez más hacia el interior de cada

  20. 西双版纳地区小型哺乳动物群落结构及其季节变动%Community structure and its seasonal variation of small mammals in Xishuangbanna of Yunnan, China

    Institute of Scientific and Technical Information of China (English)

    仝磊; 路纪琪

    2010-01-01

    2008年10月-2009年6月,选择云南西双版纳地区7个不同类型生境,分别在旱季、雾凉季和雨季,采用铗夜法对小型哺乳动物群落展开调查.共布2100铗日,捕得小型哺乳动物3科10种127只,其中啮齿目(Rodentia)鼠科(Muridae)8种,食虫目(Instectivo-ra)鼩睛科(Soricidae)和猬科(Erinaceidae)各1种,平均捕获率为6%.社鼠(Niviventer con-fucianus)是该地区小型哺乳动物群落中的优势种,其捕获率在季节之间的差异达到显著水平(P=0.023),在生境之间的差异不显著(P>0.05).在所调查的7个生境中,以生境最原始的热带雨林中的小型哺乳动物物种多样性指数最高(1.91);热带山地常绿阔叶林物种均匀度最高(0.95);热带季节性湿润林物种优势度最高(0.94).人工橡胶林中未捕获到小型哺乳动物.3个季节中以旱季捕获小型哺乳动物数量最多.对不同生境内群落相似性指数进行聚类分析,6个生境在相似性指数0.21处全部聚合在一起.本研究结果表明,不同生境中小型哺乳动物物种多样性的丰富度与人类干扰程度有关,在人类干扰越小的生境中,小型哺乳动物种类越丰富,生物多样性指数越高;人为干扰频繁