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Sample records for dasyprocta leporina rodentia

  1. 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.

  2. 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

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    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.

  3. 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

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    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

  4. 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.

  5. Perimortality in a Captive Reared Agouti (Dasyprocta leporina

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    Gary Wayne Garcia

    2015-12-01

    Full Text Available erinatal mortality has been reported in cattle, swine, goats, sheep and rabbits; however, there have been no documented reports on this phenomenon in agouti (Dasyprocta leporina. The agouti is a Neotropical polytocous rodent, hunted for its meat. This study reports on an incident of perinatal mortalities in a captive reared agouti from the wildlife unit of the Faculty of Food and Agriculture. The pluriparous female agouti was reared in captivity from birth and had delivered three (3 previous litters successfully. These ranged from 2-3 young, with a 100% survival rate. This case presented a difficult labor, with delivery of three (3 healthy female precocious offspring (434g, 378g and 402g, and three (3 perinatal mortalities (285g, 368g and 300g. The female agouti died during delivery and postmortem results indicated that Dystocia resulting in Secondary Uterine Inertia as the cause of death. This abnormally large litter may have been as a result of captive conditions, where an abundance of food and a lack of predators may have dulled the animal’s survival instinct. The agouti’s ability and the time taken to deliver all six (6 young may also have contributed to the animals delivery stress.

  6. Monitoramento do ciclo estral de cutias (Dasyprocta leporina Lichtenstein, 1823 através de citologia esfoliativa vaginal e ultrassonografia

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    Lívia B. Campos

    2015-02-01

    Full Text Available O objetivo deste estudo foi monitorar o ciclo estral em cutias (Dasyprocta leporina criadas em cativeiro no semiárido brasileiro. Durante 70 dias, cinco cutias foram diariamente submetidas a citologia esfoliativa vaginal, e o monitoramento ultrassonográfico ovariano foi realizado a cada três dias. Um total de 8 ciclos estrais foi completamente monitorado, com duração de 28,2±0,7 dias, variando de 24 a 31 dias. Pela citologia esfoliativa vaginal, houve uma predominância de células superficiais nas fases de proestro e estro (P0,05. Os folículos foram identificados durante as fases estrogênicas (proestro e estro, com diâmetro médio de 1±0,5mm. Em apenas 12,5% das fases luteais, corpos lúteos medindo 1,4±0,9mm foram identificados. Conclui-se que a associação da citologia vaginal e da ultrassonografia ovariana constitui uma alternativa viável para o monitoramento de ciclos estrais e identificação das fases estrogênicas em cutias da espécie Dasyprocta leporina

  7. 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.

  8. The lumbosacral plexus of the red-rumped agouti (Dasyprocta leporina Linnaeus, 1758 (Rodentia: Caviidae

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    Gleidson Benevides de Oliveira

    2016-12-01

    Full Text Available The red-rumped agouti is a small-sized wild rodent, belonging to the Dasyproctidae family, with great zootechnical potential, and it adapts well to captivity. In order to contribute to the species biology, this study describes the origin of the nerves forming the lumbosacral plexus. Twelve animals (six males and six females were used, from previous experiments. The animals were fixed in a 10% formaldehyde aqueous solution and eviscerated after 72 hours. Then, the major and minor psoas muscles were retracted, exposing the nerves forming the plexus. Cotton soaked with 20-volume hydrogen peroxide was placed on these nerves, remaining for 12 hours straight for bleaching and subsequent dissection. The topographical relations of the lumbosacral plexus were grouped into tables and arranged in terms of simple percentage. In 7 cases (58.34%, the lumbosacral plexus in the red-rumped agouti stemmed from the ventral roots of the last 4 lumbar nerves and the first 3 sacral nerves (Type I – L4-S3, in 4 animals (33.33% it stemmed from L5-S3 (Type II, and in 1 case (8.33% it stemmed from L5-S4 (Type III. The nerves participating of the lumbosacral plexus in the red-rumped agouti were: lateral femoral cutaneous, genitofemoral, femoral, obturator, sciatic, cranial gluteal, caudal gluteal, and pudendal nerve. The origin of the lumbosacral plexus and the spinal nerves making up this plexus in red-rumped agoutis were similar to that described in other rodents, such as rock cavy, lowland paca and spix's yellow-toothed cavy.

  9. 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

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    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.

  10. Morfologia das glândulas salivares maiores em cutias (Dasyprocta leporina Linnaeus, 1766

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    Carlos M. Oliveira Júnior

    2016-03-01

    Full Text Available Resumo: Estudos acerca da morfologia de animais silvestres servem de subsídio para trabalhos de manejo e preservação de diferentes espécies, pois fornecem informações para a tomada de medidas que auxiliem na manutenção destes em cativeiro, na preservação em habitat natural ou mesmo para ações voltadas a reintrodução ao habitat de origem. Estudos referentes à morfologia de cutias abordam os diversos sistemas, mas nenhum faz referência à arquitetura ou estrutura de suas glândulas salivares. Assim este trabalho objetivou descrever macro e microscopicamente as glândulas salivares maiores de cutias. Foram utilizados dez animais adultos para o desenvolvimento de metodologias relativas à macroscopia propriamente dita das glândulas, microscopia de luz, microscopia eletrônica de transmissão e microscopia eletrônica de varredura. Foram identificadas quatro glândulas salivares maiores nos animais estudados, denominadas parótida, mandibular, zigomática e sublingual. As glândulas apresentaram-se como sendo do tipo tubuloacinares e contendo em seu parênquima ductos dos mais variados tamanhos. Com exceção da glândula parótida, que era estritamente serosa, as demais eram mistas. Da mesma forma, apenas a glândula mandibular foi identificada a presença de ducto do tipo granuloso. Apresentando as cutias os quatro pares de glândulas salivares maiores, estes animais podem servir de modelo para os estudos acerca das mudanças anatômicas sofridas pelos roedores para se adaptar aos diversos habitat do planeta.

  11. The subplacenta of the red-rumped agouti (Dasyprocta leporina L)

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    Rodrigues, Rosangela Felipe; Carter, Anthony M.; Ambrosio, Carlos Eduardo;

    2006-01-01

    . We here describe the subplacenta of the red-rumped agouti and examine the possible functional correlates of this structure. METHODS: Placentae were collected from early in midgestation to near term of pregnancy and examined by standard histological techniques, immunohistochemistry and transmission...... of lacunae. Microvilli project into these lacunae from the plasma membrane of the syncytiotrophoblast. The syncytial cytoplasm contains electron-dense granules. This is probably the amylase-resistant PAS-positive material identified by histochemistry. The subplacenta is supplied entirely from the fetal...... circulation. Within it the vessels pursue a tortuous course with sinusoidal dilatations and constrictions. CONCLUSION: The functions that have been attributed to the subplacenta include hormone production. Our findings are consistent with this interpretation, but suggest that hormone secretion is directed...

  12. The organization of the brainstem nuclei associated with the vagus nerve in the Agouti (Dasyprocta leporina). A neurohistological study.

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    Phillips, C M; Odekunle, A

    2011-01-01

    A total of six adult animals were used for the study. Following anaesthesia via intraperitoneal injection of a mixture of ketamin and bombazine in ratio 2:1, thoracotomy was performed to exteriorize the heart for intracardial perfusion. The perfusion canular was inserted into the left ventricle and animal perfused sequentially with normal saline and 10% formal saline. Following perfusion, craniotomy was performed to remove the entire brain along with the upper segments of the spinal cord. The brain specimen was then dehydrated, cleared and infiltrated with paraffin wax. The specimen was then cut in 15 micron thick serial sections. The sections were then processed for neurohistological analyses using a Nikon microscope to which was attached Nikon camera. Analyses of the sections revealed bilateral representation of the dorsal motor nucleus of the vagus nerve in the medulla oblongata. The nucleus ambiguus, nucleus of the tractus solitarius, hypoglossal nucleus and the area postrema were also identified in the medulla oblongata. The implications of our findings are discussed in the text of the article.

  13. The organization of the brainstem nuclei associated with the vagus nerve in the Agouti (Dasyprocta leporina). A neurohistological study

    National Research Council Canada - National Science Library

    Phillips, C M; Odekunle, A

    2011-01-01

    ...:1, thoracotomy was performed to exteriorize the heart for intracardial perfusion. The perfusion canular was inserted into the left ventricle and animal perfused sequentially with normal saline and 10% formal saline...

  14. Morfologia da laringe de cutia (Dasyprocta sp.

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    Andrezza B.S. Silva

    2014-06-01

    Full Text Available A cutia (Dasyprocta sp. é um roedor silvestre com distribuição mundial. Atualmente, além de importante papel ecológico que exerce, está sendo utilizada como modelo em experimento animal. Estudos sobre a morfologia destes animais são importantes porque podem ser uma alternativa para o estudo de diversos processos patológicos, além de contribuirem para a preservação da espécie. A laringe é um órgão localizado entre a faringe e a traqueia, no qual está envolvido nas funções de respiração, deglutição e fonação. O presente estudo propôs realizar uma descrição morfológica macroscópica e microscópica da laringe da cutia. Para tanto, foram utilizadas quinze cutias pertencentes ao Centro de Ciências Agrárias da Universidade Federal do Piauí e provenientes do Núcleo de Estudos e Preservação de Animais Silvestres com licença do IBAMA (Nº 02/08-618, CTF Nº 474064. Todos os animais foram identificados, promovida a sexagem e, posteriormente, a laringe acessada e dissecada sendo os fragmentos cartilagíneos encaminhados para rotina histológica e corados pelo método de hematoxilina-eosina. As lâminas obtidas foram visualizadas em microscopia óptica de luz e foto documentadas. A laringe da cutia apresenta cinco cartilagens, com ausência da cartilagem cuneiforme e presença da incisura caudal na cartilagem tireoide. O tecido epitelial da laringe varia de epitélio estratificado pavimentoso queratinizado à não queratinizado e ciliado com células caliciformes.

  15. The morphology of the pineal gland of the yellow-toothed cavy (Galea Spixii Wagler, 1831) and red-rumped agouti (Dasyprocta leporina linnaeus, 1758).

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    Câmara, Felipe Venceslau; Lopes, Igor Renno Guimarães; de Oliveira, Gleidson Benevides; Bezerra, Ferdinando Vinicius Fernandes; de Oliveira, Radan Elvis Matias; Oliveira Júnior, Carlos Magno; Silva, Alexandre Rodrigues; de Oliveira, Moacir Franco

    2015-08-01

    The pineal gland is an endocrine gland found in all mammals. This article describes the morphology of this important gland in two species of Caviideae, namely the yellow-toothed cavy and the red-rumped agouti. Ten adult animals of the two species used in current analysis were retrieved from the Center for the Multiplication of Wild Animals (CEMAS/UFERSA) and euthanized. The glands were removed and photographed in situ and ex situ. They were fixed in a paraformaldehyde solution 4% or glutaraldehyde 2.5% solution and submitted to routine histological techniques respectively for light and scanning electron microscopy. Macroscopically, the pineal gland with its elongated structure may be found between the cerebral hemispheres facing the rostral colliculi. Microscopically, pinealocytes and some glia cells were predominant. Contrastingly, to the cavy's pineal gland, a capsule covered the organ in the agouti, with the emission of incomplete septa to the interior, which divided it into two lobules. Light and scanning electron microscopes failed to show calcareous concretions in the pineal gland. Based on the topography of the cavy's and agouti's pineal gland, it may be classified as supra-callosum and ABC type.

  16. Macroscopic description of teeth of Azara's agouti (Dasyprocta azarae

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    Fabrício S. Oliveira

    2012-01-01

    Full Text Available The teeth of Azara's agouti (Dasyprocta azarae were described macroscopically in order to provide biological data on one of the largest wild rodents of the Americas. Radiography was taken on six heads and the teeth were described. Enamel surrounds the coronal dentin, projects to the roots and is present as parallel inner laminae in buccolingual direction. The dentin is located among the enamel laminae and surrounds the pulp horns. The cementum is located internally to the enamel laminae. On the lingual surface, the cementum and dentin are the outer elements.

  17. DESCRIÇÃO HISTOLÓGICA DOS INCISIVOS DA CUTIA Dasyprocta prymnolopha (Wagler, 1831)

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    Weber Leal de Moura; Adriana Maria Viana Nunes Pinheiro; Débora Cavalcante Braz; Maria Acelina de Carvalho

    2006-01-01

    Esse trabalho objetivou descrever a histologia do dente e do periodonto de cutia. Utilizaram-se dez exemplares de Dasyprocta prymnolopha, desconsiderando idade e sexo. Realizado o processamento histológico clássico, o esmalte e o cemento desintegraram-se na descalcificação, evidenciando-se que o cemento apresenta uma quantidade de tecido mineralizado maior que a dentina. Na dentina, observaram-se túbulos dentinários, estriações paralelas, flexíveis, sinuosas e perpendiculares ao eixo maior do...

  18. Segmentos anátomo-cirúrgicos arteriais do rim de cutia (Dasyprocta prymnolopha Anatomical-surgical arterial segments of the kidney in agouti (Dasyprocta prymnolopha

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    Maria A.M. Carvalho

    2008-05-01

    Full Text Available Foram estudados 20 pares de rins decutias (Dasyprocta prymnolopha Wagler, 1831, com o objetivo de descrever os segmentos anátomo-cirúrgicos arteriais. As artérias renais foram injetadas com solução de Vinilite corada, e os rins foram submetidos à corrosão ácida para a obtenção dos moldes vasculares. Observou-se que as artérias renais da cutia, sempre únicas, dividiram-se em artéria setorial ventral e artéria setorial dorsal, caracterizando dois setores renais separados por plano avascular. As artérias setoriais penetraram no hilo renal (100% dos casos. Estes vasos deram origem aos ramos segmentares responsáveis pela irrigação de territórios independentes em cada setor, os segmentos arteriais renais. No rim direito foram observados 3 (60%, 4 (35% e 5 segmentos (5% no setor arterial ventral e 3 (30%, 4 (45%, 5 (20% e 6 (5% segmentos no setor dorsal e, à esquerda, 2(10%, 3 (55% e 4 (35% segmentos no setor ventral e 3 (25%, 4 (50% e 5 (25% no dorsal. Com base na distribuição arterial nos rins de cutia, observaram-se setores e segmentos arteriais independentes, sendo possível, desta forma, a realização de setoriectomia e segmentectomia nesta espécie.Twenty pairs of agouti (Dasyprocta prymnolopha Wagler, 1831 kidneys were studied to describe the arterial anatomical-surgical segments. The renal arteries were injected with stained acetate vinyl, followed by procedures of acid corrosion in order to obtain vascular casts. It was found that the renal artery is always single and bifurcated into ventral and dorsal sectorial arteries. The sectorial arteries reached the kidneys (100% of the cases through the hilus. These vessels gave origin to segmental branches responsible for kidney irrigation. At the right kidney, the ventral sectorial arteries gave origin to 3 (60% of the cases, 4 (35% and 5 (5% segmental branches; the dorsal sectorial arteries gave origin to 3 (30%, 4 (45%, 5 (20% and 6 (5% segmental arteries separated by a

  19. DESCRIÇÃO HISTOLÓGICA DOS INCISIVOS DA CUTIA Dasyprocta prymnolopha (Wagler, 1831

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    Weber Leal de Moura

    2006-10-01

    Full Text Available Esse trabalho objetivou descrever a histologia do dente e do periodonto de cutia. Utilizaram-se dez exemplares de Dasyprocta prymnolopha, desconsiderando idade e sexo. Realizado o processamento histológico clássico, o esmalte e o cemento desintegraram-se na descalcificação, evidenciando-se que o cemento apresenta uma quantidade de tecido mineralizado maior que a dentina. Na dentina, observaram-se túbulos dentinários, estriações paralelas, flexíveis, sinuosas e perpendiculares ao eixo maior do dente, presentes em maior quantidade na região próxima à pré-dentina. A dentina foi classificada em peritubular, intertubular e interglobular, além da pré-dentina, delgada porção não mineralizada. Os odontoblastos mostraram-se acidófilos, paralelos, dispostos ‘’em paliçada’’, ocupando o espaço entre a dentina e a polpa. A polpa apresentou tecido conjuntivo frouxo bastante vascularizado e inervado, cujas células predominantes foram fibroblastos de aspecto estrelado e fusiforme com longos prolongamentos citoplasmáticos. O periodonto mostrou cemento, ligamento periodontal e osso alveolar. O ligamento foi classificado em inferior (conjuntivo denso e superior (conjuntivo frouxo com o primeiro apresentando áreas globulares provenientes da comunicação do osso alveolar e o segundo um epitélio juncional pseudo-estratificado. As fibras de Sharpey partiam do ligamento, inserindo-se no osso alveolar,cujas lamelas formariam delgadas trabéculas e de osso compacto formado pelos sistemas de Havers. PALAVRAS-CHAVE: Dente, dentino-pulpar, Dasyprocta periodonto.

  20. Anatomical and histological characteristics of teeth in agouti (Dasyprocta prymnolopha Wagler, 1831

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    Daiane C. Baia da Silva

    2013-12-01

    Full Text Available The agouti species Dasyprocta prymnolopha (D. prymnolopha is a medium-sized rodent, diurnal, and characteristic of northeastern Brazil, south of the Amazon. Several studies have been made on these rodents. However, there is a lack of analysis of masticatory system, in particular morphology of the teeth. Thus, this research seeks to describe anatomical and histological aspects of the agouti teeth. For this purpose, we used adult agouti, in which measurements and descriptions of teeth and dental tissues were made. It was observed that the dental arch of D. prymnolopha comprises of twenty teeth, evenly distributed in the upper and lower arch, being inferior teeth larger than their corresponding higher. The incisors are larger, and between the posterior premolars and molars, there is a gradual increase in length in the anterior-posterior arch. In microscopic examination, a prismatic appearance was observed consisting of enamel prisms arranged in different directions, behind the enamel and dentin with standard tubular dentinal tubules with variable diameter and far between, also showing a sinuous path from the inner portion to the junction with more superficial enamel. Morphological analysis of dental tissues showed that an enamel with structural organization adapted to the act of chewing and high impact dentin compatible with standard tubular function resilience and mechanical damping of masticatory forces, as found in larger animals, confirming the understanding of eating habits that define much of its ecological functions within the ecosystem they inhabit.

  1. Computerized electrocardiogram in agoutis (Dasyprocta prymnolopha Wagler, 1831 anesthetized with ketamine and midazolam

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    Anaemilia N. Diniz

    Full Text Available ABSTRACT: An electrocardiogram is a test that assesses heart electrical activity and is applied more frequently in the veterinary care of wild animals. The present study aimed to define the electrocardiogram pattern of agoutis (Dasyprocta prymnolopha Wagler, 1831 anesthetized with ketamine and midazolam. Eighteen clinically healthy agoutis (D. prymnolopha were used from the Nucleus for Wild Animal Studies and Conservation (NEPAS of the Federal University of Piauí, Brazil. The animals were chemically restrained with 5% ketamine hydrochloride at a dose of 15mg/kg and midazolam at a dose of 1mg/kg by intramuscular injection. Electrocardiogram tests were carried out by a computerized method with the veterinary electrocardiogram [Acquisition Model for Computer (ECG - PC version Windows 95 Brazilian Electronic Technology (TEB consisting of an electronic circuit externally connected to a notebook computer with ECGPC-VET (TEB software installed on the hard disc. In analysing the EKG results, significant differences were observed for QRS complex duration, PR and QT intervals and for R wave millivoltage between the genders; but we observed a significant influence of weight despite the gender. In the present experiment, the anaesthetic protocol was shown to be well tolerated by the agoutis, and no arrhythmias occurred during the time the animals were monitored. The reference values obtained should be used to better understand the cardiac electrophysiology of the species and for its clinical and surgical management.

  2. Paca (Agouti paca and Agouti (Dasyprocta spp. - Minili-vestock Production in the Amazonas State of Venezuela : 1. Biology

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    Govoni, G.

    2001-01-01

    Full Text Available In response to increasing human population pressure in the Amazonas State of Venezuela greater attention is being given to the "minilivestock" production of the wild rodents paca (Agouti paca, and agouti (Dasyprocta spp as sources of food and income and to reduce the risk of their possible extinction. In preparation for the increased farming of these rodents, this paper reviews published material on their characteristics, distribution, habitat, conservation status, behaviour, reproductive parameters and nutrition. It is concluded that the two rodents paca and agouti, have characteristics that justify greater investment in their domestication and farmed production, although and behavioural issues and reproductive limits need further research.

  3. Structural and ultrastructural features of the agouti tongue (Dasyprocta aguti Linnaeus, 1766).

    Science.gov (United States)

    Ciena, Adriano Polican; de Sousa Bolina, Cristina; de Almeida, Sonia Regina Yokomizo; Rici, Rose Eli Grassi; de Oliveira, Moacir Franco; da Silva, Marcelo Cavenaghi Pereira; Miglino, Maria Angélica; Watanabe, Ii-sei

    2013-08-01

    The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three-dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V-shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell-surface microridges were observed. These structural features, including the three-dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae.

  4. 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

  5. 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

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

    NARCIS (Netherlands)

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

    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

  7. Colheita de sêmen por eletroejaculação em cutia-parda (Dasyprocta azarae Semen collection by electroejaculation in Azara´s agouti (Dasyprocta azarae

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    Antonio C. Martinez

    2013-01-01

    Full Text Available As cutias são animais que vivem nas Américas Central e do Sul, com potencial zootécnico e que despertam crescente interesse científico. O objetivo deste estudo foi estabelecer um padrão para colheita de sêmen por eletroejaculação em cutia-parda (Dasyprocta azarae. Foram utilizados machos adultos (n=4 anestesiados e submetidos a quatro séries de 20 estímulos eletroejaculatórios, com 3 segundos de duração cada, com uma intensidade de 2, 4, 6 e 8 volts, com dois minutos de intervalo entre cada série. A colheita de sêmen foi obtida em todos os animais, com ereção parcial com 2 volts, ereção evidente com 4 volts, ejaculação com 6 volts e exacerbação da glande e exteriorização das espículas penianas com 8 volts, observando-se espermatozoides em 100% das amostras. A técnica descrita para colheita de sêmen em cutia-parda foi eficaz.Agoutis are animals that live in South and Central America, present rearing potential and call increasing scientific interest. The aim of this paper was to establish a model for semen collection by electroejaculation in Azara´s agouti (Dasyprocta azarae. Anesthetized adult males (n=4 were submitted to four series of 20 electroejaculatory stimuli, during 3 seconds each and with 2, 4, 6 and 8 volts, with a 2 minutes rest among series. Semen collection was accomplished in every animal, with partial penis erection at 2 volts, makeable erection at 4 volts, ejaculation at 6 volts, glans and penis spines exposition at 8 volts, and sperm collected in all samples. The described technique for Azara's agouti semen collection was efficient.

  8. Análise qualitativa do estabelecimento da espermatogênese em cutias (Dasyprocta aguti criadas em cativeiros

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    Antônio Chaves de Assis-Neto

    2003-01-01

    Full Text Available A determinação do estabelecimento da puberdade é bastante estudada em animais domésticos e roedores, no entanto, são escassas as pesquisas com a finalidade de estabelecer parâmetros para a biologia reprodutiva em cutias. Foram utilizadas 31 cutias machos da espécie Dasyprocta agouti, oriundas da Universidade Federal do Piauí, Estado do Piauí, e da Escola Superior de Agricultura de Mossoró, Estado do Rio Grande do Norte. Imediatamente após a orquiectomia foram retirados fragmentos e estes foram processados histologicamente, os tecidos foram corados com hematoxilina-eosina e analisou-se os parâmetros seguintes: aspectos de luminação dos túbulos seminíferos; presença de espermatócitos primários; presença de espermátides e formação dos primeiros estágios do ciclo do epitélio seminífero (CES segundo o método da morfologia tubular. O período desde o nascimento até os cinco meses de idade correspondeu à fase impúbere; dos seis aos oito meses de idade a fase de transição da pré-puberdade à puberdade; dos nove aos dez meses de idade à fase da puberdade; e dos doze aos quartoze meses de idade à fase da pós-puberdade. A puberdade da cutia (Dasyprocta aguti, ocorreu em animais a partir dos sete meses de idade, e o estabelecimento da puberdade foi constatado em todos os animais estudados aos nove meses de idade.

  9. Determinação da taxa metabólica basal em cutias, Dasyprocta azarae, por calorimetria indireta Determination of the basal metabolic rate in agoutis, Dasyprocta azarae, by indirect calorimetry

    Directory of Open Access Journals (Sweden)

    Harald F.V. Brito

    2010-06-01

    Full Text Available A melhor ferramenta para comparação fisiológica entre organismos diferentes é a taxa metabólica basal, inter-relação fundamental que existe entre todos os seres vivos. Mensurações diretas das concentrações de oxigênio e dióxido de carbono, pela análise do ar inspirado e expirado, podem ser usadas para a mensuração de taxa metabólica. Este trabalho foi executado com o propósito de aferir as taxas metabólicas basal e específica, e reexaminar o escalonamento do metabolismo basal em cutias (Dasyprocta azarae. Foram utilizadas 34 cutias (D. azarae adultas sadias, sendo 9 machos não castrados, 9 machos castrados e 16 fêmeas, pertencentes ao plantel do Criadouro Científico do Museu de História Natural Capão da Imbuia, Curitiba, PR. Os animais passaram por jejum prévio de 6 horas e foram acondicionados em caixas especiais, com temperatura ambiente controlada (22,0±1,0ºC, sendo então submetidos à aferição da taxa metabólica basal, por calorimetria indireta. Empregou-se o monitor metabólico Deltatrac®II, (Datex Ohmeda, Finlândia usualmente indicado para a mensuração da produção de dióxido de carbono (VCO2 e do consumo de oxigênio (VO2 em seres humanos, por meio da mensuração das variações na concentração de VCO2 e de VO2, com uma precisão de 0,01%. Após a aferição da taxa metabólica basal, foi calculada a taxa metabólica específica, e efetuada a análise dos dados por estatística indutiva. Os testes de hipóteses para comparação entre amostras indicaram que a taxa metabólica específica de machos não castrados é maior que a de fêmeas e machos castrados (5% de significância, e que a taxa metabólica específica de fêmeas e machos castrados é equivalente (1% de significância. Constatou-se ainda, com a análise da correlação de pontos experimentais, que outra variável que não o tamanho corporal afeta a taxa metabólica dos machos não castrados (1% de significância, o que indica a

  10. Colheita de sêmen por eletroejaculação em cutia-parda (Dasyprocta azarae

    Directory of Open Access Journals (Sweden)

    Antonio C. Martinez

    2013-01-01

    Full Text Available As cutias são animais que vivem nas Américas Central e do Sul, com potencial zootécnico e que despertam crescente interesse científico. O objetivo deste estudo foi estabelecer um padrão para colheita de sêmen por eletroejaculação em cutia-parda (Dasyprocta azarae. Foram utilizados machos adultos (n=4 anestesiados e submetidos a quatro séries de 20 estímulos eletroejaculatórios, com 3 segundos de duração cada, com uma intensidade de 2, 4, 6 e 8 volts, com dois minutos de intervalo entre cada série. A colheita de sêmen foi obtida em todos os animais, com ereção parcial com 2 volts, ereção evidente com 4 volts, ejaculação com 6 volts e exacerbação da glande e exteriorização das espículas penianas com 8 volts, observando-se espermatozoides em 100% das amostras. A técnica descrita para colheita de sêmen em cutia-parda foi eficaz.

  11. 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.

  12. INDICADORES HEMATOLÓGICOS Y HEMOQUÍMICOS DE Dasyprocta fuliginosa (GUARA, GUATÍN O ÑEQUE) EN CAUTIVERIO

    OpenAIRE

    Lizcano L.; Estrada G.; Orozco O.; Núñez P.

    2006-01-01

    Los indicadores hematológicos y hemoquímicos de la Dasyprocta fuliginosa (guara, guatín o ñeque) en cautiverio se realizaron en el municipio de Florencia, Caquetá (Colombia), pretendiendo iniciar una referencia de datos para estudios de conservación, manejo productivo y clínico de la especie. Fueron utilizados diez animales machos en dos estados de desarrollo (juveniles y adultos). Para hemograma se determinaron hematocrito (técnica de microhematocrito), hemoglobina (método espectrofotométric...

  13. Uso do propofol na indução anestésica de cutias (Dasyprocta sp. Use of propofol in the induction of anesthesia in agouti (Dasyprocta sp.

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    W.P. Leite

    2008-08-01

    Full Text Available Avaliou-se o emprego do propofol, por via intravenosa, como agente indutor anestésico em cutias (Dasyprocta sp, utilizando-se 10 fêmeas adultas, com pesos entre 1,5 a 2,0kg, criadas em cativeiro. Avaliaram-se as freqüências cardíaca e respiratória, a temperatura retal e a pressão arterial sistólica, antes da administração do propofol e logo após a anestesia dos animais. Foram mensurados o período hábil e de recuperação da anestesia. As médias das freqüências cardíaca e respiratória, temperatura retal e a pressão arterial sistólica basais foram de 220bcm, 92mrm, 38,95ºC e 110mmHg, respectivamente. Após a indução, as médias obtidas para essas variáveis foram de 214bcm, 84mrm, 39,05ºC e 80mmHg. As médias dos períodos hábil e de recuperação da anestesia foram de 10min e 45seg e 15min e 40seg, respectivamente. O propofol, quando utilizado em dose única, mostrou-se seguro, não alterando significativamente os parâmetros fisiológicos, podendo ser considerado um fármaco de escolha para a indução anestésica de cutias.The endovenous use of propofol as inductor agent of anesthesia in agouti (Dasyprocta sp. was evaluated using ten adut females, weighing 1.5 to 2.0kg, kept in captivity. Heart and respiratory rates, rectal temperature, and systolic arterial blood pressure were measured before and after anesthesia. Time of anesthesia and time of recovering of the anesthesia were also measured. The averages of the heart and respiratory rates, rectal temperature and the systolic blood pressure were 220bpm, 92mpm, 38.95ºC, and 110Hgmm, respectively. After the induction, the averages obtained for those variables were of 214bpm, 84mpm, 39.05ºC, and 80mmHg, respectively. The averages of the time of anesthesia and time of its recovery were 10min 45sec and 15min 40sec, respectively. Propofol when used in only one dose, was considered safe, since it did not disturbe the physiological parameters. Thus, propofol can be

  14. Karyotype restructuring in Rodentia: from evolution to cancer

    OpenAIRE

    Pereira, Sandra Louzada Gomes

    2015-01-01

    Tese de Doutoramento em Genética Molecular Comparativa e Tecnológica A ordem Rodentia representa a mais abundante e diversificada ordem de mamíferos. A análise dos cariótipos/genomas de roedores da superfamília Muroidea tem revelado a ocorrência de elevadas taxas de evolução para estas espécies, o que as torna bons modelos para o estudo da evolução de cromossomas, dos rearranjos cromossómicos e das consequências dos mesmos durante o processo tumoral. O principal objectivo desta...

  15. Plasma concentration of progesterone and 17ß-estradiol of black-rumped agouti (Dasyprocta prymnolopha during the estrous cycle

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    Diva Anelie Guimarães

    2011-03-01

    Full Text Available Plasma concentration of progesterone and 17β-estradiol of black-rumped agouti (Dasyprocta prymnolopha during the estrous cycle. The agouti is a game animal that have been raised in captivity for conservation and sustainability purposes. However, the management of wild animals in an intensive breeding system requires an assertive knowledge of its reproductive parameters, one of the most important features for production improvement. Besides, little information is available regarding changes in reproductive hormone profiles in agouti. The objective of this study was to evaluate the hormonal profile of progesterone and 17β-estradiol during the estrous cycle of the agouti (Dasyprocta prymnolopha. The hormones were analyzed by radioimmunoassay. Blood samples were collected without sedation twice a week. The concentrations of progesterone were as follows: proestrus 0.78+0.39ng/ml, estrus 2.83+2.34ng/ml, metestrus 1.49+1.24ng/ml, diestrus 3.71+1.48ng/ml. In the estrous phase, an increase in the progesterone level was observed during a period of 24h. The average 17 β-estradiol levels were as follows: proestrus 2 030.98+961.00pg/ml, estrus 1 910.56+650.54pg/ml, metestrus 1 724.83+767.28pg/ml, diestrus 1 939.94+725.29pg/ml. The current results suggest that the progesterone plasma concentration during the estrous cycle in the agouti has a similar increasing, stabilizing and decreasing pattern, as in domestic mammals. Agoutis have two phases of follicular development, as two periods of 17β-estradiol peaks were observed, the first one in the metestrus and the second during the proestrus. Spontaneous ovulation seems to occur after the progesterone peak, possibly indicating that this hormone is associated with the ovulatory process. A more detailed investigation is needed for better understanding of how progesterone influences ovulation. Studies on the involvement of progesterone in follicular rupture can be carried out, using steroid biosynthesis

  16. Phenomenon in the Evolution of Voles (Mammalia, Rodentia, Arvicolidae

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    Rekovets L. I.

    2017-04-01

    Full Text Available This paper presents analytical results of the study of adaptatiogenesis within the family Arvicolidae (Mammalia, Rodentia based of morphological changes of the most functional characters of their masticatory apparatus — dental system — through time. The main directions of the morphological differentiation in parallel evolution of the arvicolid tooth type within the Cricetidae and Arvicolidae during late Miocene and Pliocene were identified and substantiated. It is shown that such unique morphological structure as the arvicolid tooth type has provided a relatively high rate of evolution of voles and a wide range of their adaptive radiation, as well as has determined their taxonomic and ecological diversity. The optimality of the current state of this group and evaluation of evolutionary prospects of Arvicolidae were presented and substantiated here as a phenomenon in their evolution.

  17. [Molecular characterization of Sigmodon hirsutus (Rodentia: Cricetidae) populations in Venezuela].

    Science.gov (United States)

    Lessmann, Janeth; Arrivillaga, Jazzmín; Aguilera, Marisol

    2011-06-01

    Recent phylogenetic studies based on cytochrome b gene sequence, have determined that the species historically known as Sigmodon hispidus (Rodentia) from South America comprises a species S. hirsutus of paraphyletic origin. The aim of this study was to test the hypothesis that populations from Venezuela, represent the sensu strict form, ancestral haplotypes, and monophyletic subspecieS. For this, 12 individual sequences from three localities of different biogeographic regions in Venezuela were evaluated and sequenced based on cyto b. Additionally, the sequences were used to develop a cladistic analysis and genetic distance calculations, and to compare this information with two individual sequences of Sigmodon specimens available in Genbank. Phylogenetic analyses show that the three populations of S. hirsutus of Venezuela form an ancestral and monophyletic subclade supported by high bootstrap values and significant genetic distance between subclade within the S. hirsutus. Besides, the existence of two lineages suggests two subspecies, S. hirsutus hirsutus from Venezuela, and S. hirsutus mexicanus from Mexico-Central America, but, both species need formal description.

  18. 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.

  19. INDICADORES HEMATOLÓGICOS Y HEMOQUÍMICOS DE Dasyprocta fuliginosa (GUARA, GUATÍN O ÑEQUE EN CAUTIVERIO

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    Lizcano L.

    2006-11-01

    Full Text Available Los indicadores hematológicos y hemoquímicos de la Dasyprocta fuliginosa (guara, guatín o ñeque en cautiverio se realizaron en el municipio de Florencia, Caquetá (Colombia, pretendiendo iniciar una referencia de datos para estudios de conservación, manejo productivo y clínico de la especie. Fueron utilizados diez animales machos en dos estados de desarrollo (juveniles y adultos. Para hemograma se determinaron hematocrito (técnica de microhematocrito, hemoglobina (método espectrofotométrico de la cianometahemoglobina, recuento total de leucocitos (técnica del hemocitómetro y recuento diferencial de leucocitos (frotis sanguíneo coloreado, y en hemoquímica se determinó glicemia (método GOD-PAP, colesterol (método CHOD-PAP, triglicéridos (método GPO-PAP, proteínas totales (método Biuret y creatinina (método colorimétrico simétrico. Los valores promedios para los parámetros evaluados en hemograma fueron: hematocrito 49,9 ± 2,9%; hemoglobina 16,5 ± 1,1 g/dl; recuento leucocitario total 6650 ± 1276,9 leucocitos/mm3; neutrófilos 17,7 ± 12,9%; linfocitos 77,6 ± 12,4%, y eosinófilos 5,1 ± 3,2 %. Para hemoquímica los resultados fueron: glicemia 249,9 ± 47,1 mg/dl; colesterol 108,1 ± 20,1 mg/dl; triglicéridos 108,1 ± 20,1 mg/dl, proteínas totales 5,7 ± 0,6 g/dl, y creatinina 1,7 ± 0,2 mg/dl. En algunos individuos los valores se desviaron significativamente del promedio, debiéndose tal vez a circunstancias fisiológicas e individuales (estrés, respuesta a mecanismos externos o por lesiones que padecían días antes a la toma de la muestra. Los indicadores del hemograma estuvieron en promedios similares a los de otros roedores del piedemonte amazónico: Proechimys sp., Agouti paca e Hydrochaeris hydrochaeris, al igual que en los hemoquímicos, salvo en glicemia, en donde se encontraron mayores valores para Dasyprocta fuliginosa, debido posiblemente al régimen alimenticio que se basaba sobre todo en frutas y

  20. 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.

  1. 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.

  2. 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.

  3. Alterações patológicas do sistema genital de cutias (Dasyprocta aguti Linnaeus, 1758 fêmeas criadas em cativeiro

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    Jael S. Batista

    Full Text Available Resumo: Este artigo apresenta relatos de sete distintas patologias de origem reprodutiva ainda não descritas em cutias (Dasyprocta aguti Linnaeus, 1758 fêmeas, que afetaram a fertilidade ou resultaram na morte do animal. Descreveu-se a natureza, a localização e a frequência das alterações patológicas macroscópicas e histológicas dos órgãos que compõem o sistema reprodutivo de cutias fêmeas, criadas sob condições de cativeiro no semiárido do Brasil. Foram avaliados através do exame anatomopatológico o aparelho reprodutivo de trinta e nove cutias mortas naturalmente e encaminhadas ao Laboratório de Patologia Veterinária, no período de fevereiro de 2010 a maio de 2015. Destas, constatou-se alterações patológicas no sistema reprodutivo de 10 (25,6 %. No total, 13 alterações foram observadas, sendo que, em alguns animais haviam a coexistência de mais de uma alteração. Assim, as alterações patológicas encontradas foram: endometrite (n=4; 30,8%, piometra (n=3; 23%, retenção de placenta (n=2; 15,4%, maceração fetal (n=1; 7,7%, mumificação fetal (n=1; 7,7%, parto distócico (n=1; 7,7% e ovários afuncionais (n=1; 7,7%.

  4. Níveis iônicos e enzimáticos de cutias (Dasyprocta sp. hígidas, criadas em cativeiro, influência do sexo e da idade Ion and enzymatic levels of healthy agouti (Dasyprocta sp. raised in captivit. Influence of gender and age

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    E.E.A. Ribeiro

    2008-06-01

    Full Text Available Determinou-se o perfil do ionograma e enzimas hepáticas de cutias (Dasyprocta sp. saudáveis, criadas em cativeiro, como também se avaliou a influência de sexo, idade e interação sexo-idade. Foi adotado um delineamento inteiramente ao acaso, em arranjo fatorial 2 x 4 (dois sexos e quatro faixas etárias, com três repetições, totalizando 24 cutias. Foram determinados os valores para o cálcio (Ca, fósforo (P, cloretos (Cl, aspartato aminotransferase (AST, alanina aminotransferase (ALT, fosfatase alcalina (FA e gama-glutamiltransferase (GGT. Os valores médios obtidos foram: Ca= 7,62+2,59mg/dl; P= 3,91+1,41mg/dl; Cl= 58,63+16,45mg/dl; AST= 119,54+79,35UI/ml; ALT= 28,08+15,53UI/ml; FA= 26,95+14,01UI/ml e GGT= 25,34+19,44UI/ml. O valor de P foi maior nas fêmeas e da FA nos machos. Os níveis de FA diminuíram com o aumento da idade.This research studied the profile of the ionogram and hepatic enzymes of healthy agoutis (Dasyprocta sp. raised in captivity as well as evaluated the influence of gender, age and interaction gender-age. It was used a completely randomized design, in a factorial arrangement of 2 x 4 (two genders and four age groups, with three repetitions, totaling 24 agoutis. The values were determined for calcium (Ca, phosphorus (P, chlorides (Cl, aspartate aminotransaminase (AST, alanine aminotransaminase (ALT, alkaline phosphatase (ALP, and gamma-glutamyltransferase (GGT. The mean values were: Ca= 7.62±2.59mg/dl; P= 3.91±1.41mg/dl; Cl= 58.63±16,45mg/dl; AST= 119.54±79.35UI/ml; ALT= 28.08±15.53UI/ml; ALP= 26.95±14.01UI/ml, and GGT= 25.34±19.44UI/ml. The value of P was larger in females and ALP in males. As the age increased, levels of ALP decreased.

  5. 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...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

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

    Science.gov (United States)

    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.

  12. 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.

  13. 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.

  14. 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.

  15. Nitric oxide production by Peromyscus yucatanicus (Rodentia infected with Leishmania (Leishmania mexicana

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    Elsy Nalleli Loría-Cervera

    2013-04-01

    Full Text Available Peromyscus yucatanicus (Rodentia: Cricetidae is a primary reservoir of Leishmania (Leishmania mexicana (Kinetoplastida: Trypanosomatidae. Nitric oxide (NO generally plays a crucial role in the containment and elimination of Leishmania. The aim of this study was to determine the amount of NO produced by P. yucatanicus infected with L. (L. mexicana. Subclinical and clinical infections were established in P. yucatanicus through inoculation with 1 x 10 2 and 2.5 x 10 6 promastigotes, respectively. Peritoneal macrophages were cultured alone or co-cultured with lymphocytes with or without soluble Leishmania antigen. The level of NO production was determined using the Griess reaction. The amount of NO produced was significantly higher (p ≤ 0.0001 in co-cultured macrophages and lymphocytes than in macrophages cultured alone. No differences in NO production were found between P. yucatanicus with subclinical L. (L. mexicana infections and animals with clinical infections. These results support the hypothesis that the immunological mechanisms of NO production in P. yucatanicus are similar to those described in mouse models of leishmaniasis and, despite NO production, P. yucatanicus is unable to clear the parasite infection.

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

    Science.gov (United States)

    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.

  17. 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.

  18. 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.

  19. 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.

  20. 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

    Directory of Open Access Journals (Sweden)

    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.

  1. RODENTIA: MURIDAE

    African Journals Online (AJOL)

    . The aquarium was ... The totals registered on the counter for each activity were noted at .... holds the food with its forepaws while biting pieces off with the incisors. The food is .... The sex ratio of male: ..... Johannesburg: Central News Agency.

  2. Extended Longevity of Reproductives Appears to be Common in Fukomys Mole-Rats (Rodentia, Bathyergidae)

    Science.gov (United States)

    Dammann, Philip; Šumbera, Radim; Maßmann, Christina; Scherag, André; Burda, Hynek

    2011-01-01

    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. PMID:21533255

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

    Science.gov (United States)

    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. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  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

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    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. 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

  10. Actividad ovárica del tepezcuintle Agouti paca (Rodentia: Agoutidae en cautiverio

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    Rubén C Montes Pérez

    2006-09-01

    Full Text Available Se caracterizó la actividad ovárica de A. paca por medio de perfiles hormonales y estructuras ováricas. Se muestrearon ocho hembras (siete adultas y una juvenil en el criadero de la Facultad de Medicina Veterinaria y Zootecnia en el estado de Yucatán, México, durante aproximadamente dos meses. Se recolectaron muestras sanguíneas cada 3 y 6 días en animales anestesiados. Se estimaron los niveles de progesterona (P4 y 17 β estradiol (E2 sanguνneos por radioinmunoanαlisis. Las estructuras ováricas de animales muertos durante el periodo de muestreo fueron analizadas macro y microscópicamente. El ciclo ovárico duró 29±8.4 días, con niveles de 1.61±0.65 ng/ml para P4 y de 39±24 pg/ml para E2 durante la fase folicular, y de 6.18±3.70 ng/ml y 29±16 pg/ml para P4 y E2 respectivamente, en la fase luteal. Hubo diferencias (pOvarian activity of Agouti paca (Rodentia: Agoutidae under captivity. 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 Yucatán, México. 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 β 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

  11. Epidural anesthesia in agoutis (Dasyprocta azarae

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    Leandro Luis Martins

    2010-06-01

    Full Text Available In this research, the epidural anesthesia technique in nulliparous and non non-nulliparous submitted to ovarysalpingohysterectomy was studied. These are rodents belonging to the “Missina Palmeira Zancaner” municipal zoo of catanduva in São Paulo. The tranquilizationwas achieved using azaperone (4mg/kg and meperidine (4mg/kg followed by injection of cetamine (20mg/kg and xylazine (0.4mg/kg, intramuscularly from the same syringe. Subsequently, lidocaine (5mg/kg was injected into the lumbosacral space. The time of latency of the anesthesic association (4.0±1.51min, time of latency of epidural lidocaine (6.87±2.35min and time of analgesia (115.0±12.49min were analyzed, in addition to rectal temperature, which decreased 2.12±0.86°C on average from the beginning of the anesthesia to the end of its effective time. All animals recovered satisfactorily without presenting signs of excitation or complications due to the epidural tecnique. It was concluded that the balanced anesthesia tecnique provided adequate analgesia during a time considered sufficient for several procedures, by means of low doses of xylazine and ketamine.

  12. Description of a new species of Heligmosomoides (Nematoda: Heligmosomidae parasitic in Microtus limnophilus (Rodentia: Cricetidae from Rangtang, Sichuan, China

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    Massoni J.

    2010-03-01

    Full Text Available Heligmosomoides craigi n. sp. (Nematoda: Heligmosomoidea is described from Microtus limnophilus Büchner, 1889 (Rodentia: Cricetidae from Rangtang, Sichuan, China. It is related to H. protobullosus Asakawa, 1987 and H. longispiculum Tokobaev & Erkulov, 1966 both parasites of Microtus spp. from Japan and USSR, respectively by the following features: a ratio of spicule length/body length of more than 45% and rays 9 shorter than rays 10. The new species is differentiated by rays 8 being closed to rays 6 and 19-22 cuticular ridges versus 14 in H. protobullosus (synlophe not described in H. longispiculum. H. longicirratus (Schulz, 1954 also a parasite of Microtus sp. from the USSR is the most closely related species based on the number of cuticular ridges (20 and the ratio of spicule length/body length (48% versus 50%. There are no illustrations of this species and the female has not been described; for that reason, it is not possible to compare it accurately with our specimens.

  13. 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.

  14. 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.

  15. Habitat use by Oryzomys subflavus (Rodentia in an open shrubland formation in Restinga de Jurubatiba National Park, RJ, Brazil

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    H. G. Bergallo

    Full Text Available The Restinga de Jurubatiba has at least 10 plant formations, including open Clusia shrubland. This formation is composed of dense shrubs of many shapes and sizes, where Clusia hilariana is one of the most important plant species. Shrublands with Clusia (CC are poorer in plant species and less dense than shrublands without Clusia (SC. Oryzomys subflavus (Rodentia is the most abundant small mammal species in the open Clusia shrubland. We tested the hypothesis that the abundance of rodents would increase with the size of the patch and would be higher in SC shrublands. Rodents were captured, marked and released in three 780-m-long transects. At each capture site, we evaluated the shape of the shrubland patch, calculated the area and noted the category of the shrubland. Using ANCOVA, we ascertained whether the abundance of Oryzomys subflavus increased with the sampled area and used CC and SC shrublands differently. We also verified if the size of patches used by rodents varies in the same frequency as the size of available shrublands. Rodent abundance was found to increase significantly with the area. There were no differences in the size of the patches used by rodents and the frequency of the size of available patches. This finding indicates that O. subflavus, in the study area, is a generalist species that uses its habitat according to availability.

  16. Characteristics of the larval Echinococcus vogeli Rausch and Bernstein, 1972 in the natural intermediate host, the paca, Cuniculus paca L. (Rodentia: Dasyproctidae).

    Science.gov (United States)

    Rausch, R L; D'Alessandro, A; Rausch, V R

    1981-09-01

    In Colombia, the natural intermediate host of Echinococcus vogeli Rausch and Bernstein, 1972 is the paca, Cuniculus paca L. (Rodentia: Dasyproctidae). The larval cestode develops in the liver of the host, where it usually is situated superficially, partly exposed beneath Glisson's capsule. The infective larva consists of a subspherical to asymmetrical, fluid-filled vesicle, up to 30 mm in diameter, enclosed by a thick laminated membrane. It typically contains numerous chambers, often interconnected, produced by endogenous proliferation of germinal and laminated tissue, within which brood capsules arise in an irregular pattern from the germinal layer. Invasive growth by means of exogenous proliferation, typical of infections in man, was not observed in the natural intermediate host. The development of the larval cestode is described on the basis of material from pacas, supplemented by observations on early-stage lesions in experimentally infected nutrias, Myocastor coypus (Molina) (Rodentia: Capromyidae). The tissue response is characterized for early-stage, mature (infective), and degenerating larvae in the comparatively long-lived intermediate host. In addition to previously reported differences in size and form of rostellar hooks, other morphologic characteristics are defined by which the larval stage of E. vogeli is distinguished from that of E. oligarthrus (Diesing, 1863). Pathogenesis by the larval E. vogeli in man, like that by the larval E. multilocularis Leuckart, 1863, is the consequence of atypical proliferation of vesicles attributable to parasite-host incompatibility.

  17. Dos nuevas especies de Stilestrongylus (Nematoda: Heligmonellidae parásitos de peromyscus (Rodentia: Cricetidae de México

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    Jorge Falcón Ordaz

    1999-12-01

    Full Text Available Se describen dos especies nuevas del género Stilestrongylus Freitas, Lent & Almeida, 1937, parásitas de Peromyscus spp. (Rodentia: Cricetidae provenientes del Estado de Hidalgo, Mexico. Stilestrongylus peromysci n. sp. infecta a Peromyscus difficilis y se caracteriza por la presencia de 30 espínas en el synlophe para ambos sexos, así como por el nacimiento simétrico de los rayos 8 a partir de la raíz del rayo nueve. S. hidalguensis n. sp. parásita a Peromyscus sp., diferenciándose del resto de las especies congenéricas porque el macho presenta 24 espinas en el synlophe a nivel de la parte media del cuerpo y porque el arreglo de los rayos bursales es diferente en ambos lóbulos (2-2-1 derecho y 2-3 izquierdo. Se presenta una clave para la identificación de 18 de las 19 especies del género.Stilestrongylus peromysci n. sp. collected from Peromyscus difficilis (Hidalgo state, México, differs from other species in the genus in number of the spines (30 in the synlophe (both sexes and because the eigth ray arises from the root of the ninth ray; S. hidalguensis n. sp. parasited Peromyscus sp. and differs from all other congeneric species in the presence of 24 spines in the male synlophe and in the arrangement of the bursal rays (2-2-1 in the right lobe and 2-3 in the left lobe. A key to the species of Stilestrongylus is provided.

  18. Genética poblacional de cobayas de Colombia, Cavia spp. (Rodentia: Caviidae con marcadores moleculares RAPD

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    Héctor Aníbal Campos

    2008-09-01

    Full Text Available En el presente estudio, mostramos los primeros resultados moleculares de formas colombianas de Cavia. Claramente, la población silvestre de C. anolaimae fue genéticamente diferenciada de la forma doméstica, C. porcellus, tal como ha sido demostrado por otros autores utilizando resultados morfométricos, osteológicos y cariotípicos. Ambas especies mostraron un considerable nivel de diversidad genética, aunque el segundo taxon mostró niveles mayores de esta diversidad. Los niveles de heterogeneidad genética también fueron mayores entre las poblaciones de C. porcellus (F ST = 0.254 que entre las poblaciones de C. anolaimae (F ST = 0.118. Esos niveles significativos de heterogeneidad genética, y los consiguientes bajos niveles de flujo génico, fueron discutidos comparativamente con los resultados por otros autores analizando otros marcadores moleculares (citocromo-b mitocondrial. Los resultados aquí mostrados son coherentes con un complejo proceso de domesticación en Cavia porcellus.Population genetics of Colombian Guinea Pigs, Cavia spp. (Rodentia: Caviidae with RAPD molecular markers. The genus Cavia occurs in South America, mainly in grasslands.. We collected blood samples from 97 individuals in six field populations and analyzed them with RAPD molecular markers. One wild type (C. anolaimae was differentiated from the domestic form (C. porcellus, in agreement with other authors who used morphological, osteological and karyotipic results. Genetic diversity was considerable in both species, but higher in C. porcellus. The levels of genetic heterogeneity were also higher among the populations of C. porcellus (F ST = 0.254 than among the populations of C. anolaimae (F ST = 0.118. These significant levels of genetic heterogeneity, and the low levels of gene flow, were consistent with a complex domestication process for Cavia porcellus. Rev. Biol. Trop. 56 (3: 1481-1501. Epub 2008 September 30.

  19. 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.

  20. The micromammals (Lagomorpha, Eulipotyphla and Rodentia) from the Middle Pleistocene site of Cuesta de la Bajada (Teruel, Spain): Systematic study and paleoenvironmental considerations

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    Sese, C.; Soto, E.; Santonja, M.; Perez-Gonzalez, A.; Dominguez-Rodrigo, M.

    2016-07-01

    The micromammal association established in this work is the following: Lagomorpha: Oryctolagus cuniculus; Eulipotyphla: Crocidura cf. russula, cf. Sorex sp., Neomys sp., Soricidae indet. and Talpa sp.; and Rodentia: Eliomys quercinus, Apodemus cf. sylvaticus, Cricetulus (Allocricetus) bursae, Arvicola aff. sapidus, Microtus (Iberomys) brecciensis and Microtus (Terricola duodecimcostatus. This association is characteristic of the Middle Pleistocene. The morphological state of Cricetulus (A.) bursae, Arvicola aff. sapidus and Microtus (I.) brecciensis allows to place it in the advanced, but not final, Middle Pleistocene, which agrees with the numerical data of the site (243–337 ka) that places it in the MIS 8 or 9. The micromammals indicate the predominance of the open spaces with abundant vegetation mainly of herbaceous and bushes but also with some areas with trees. The climate would be of Mediterranean type, similar to the actual or perhaps a little milder and more humid. (Author)

  1. 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.

  2. 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.

  3. 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.

  4. Infecção experimental de Calomys callosus (Rodentia Cricetidae com Trypanosoma cruzi Results of the experimental infection of Calomys callosus (Rodentia with human strains of Trypanosoma cruzi

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    Monamaris M. Borges

    1982-08-01

    Full Text Available São apresentados resultados sobre a infecção experimental de Calomys callosus (Rodentia e duas cepas (Y e Berenice de Trypanosoma cruzi, isoladas de casos humanos. O estudo da evolução foi feito comparado com Mus musculus albino cepa "Swiss", quanto a prepatência, parasitemia, patência e letalidade. Análise histopatológica foi também conduzida em C. callosus, com o objetivo de verificar o tropismo tissular e agressividade das cepas neste roedor. Os experimentos mostraram que a evolução da infecção em C. Callosus foi diferente para as duas cepas de T. cruzi. A cepa Y apresentou maior parasitemia do que a cepa Berenice. O período prepatente variou com as doses utilizadas tendo sido mais curto nos animais inoculados com a cepa Y (2, 2-5, 2 dias do que naquelas com a cepa Berenice (3, 2-7 dias. Embora as duas cepas inoculadas nos C. callosus tenham-se mostrado miotrópicas, as alterações tissulares foram mais acentuadas com a Y. Os resultados obtidos abrem perspectivas quanto à possibilidade do uso de C. callosus como animal experimental para T. cruzi.An albino "swiss" strain of Mus musculus was used for comparison purposes with regard to the following parameters: parasitemia, prepatent period, patency of the infection and lethality. Histopathological studies were carried out with the aim of observing the tissue tropism and aggressiveness of T. cruzi against C. callosus. The experiments showed that the evolution of the infection in C. callosus was different according to the two T. cruzi strains utilized. They strain produced higher parasitemia than the Berenice strain. The prepatent period varied as a result of the inocula being shorter in the animals inoculated with the strain Y (2, 2-3, 2 days than in those infected with the Berenice strain (3, 2-7, 0 days. Although both strains were shown to be myotropic, the tissue alterations were more pronounced in the animals inoculated with the Y strain. Results indicated the possibility

  5. Estructura genética de un grupo de capibaras, Hydrochoerus hydrochaeris (Rodentia: Hydrocheridae en los Llanos orientales colombianos

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    Adriana Maldonado-Chaparro

    2011-12-01

    Full Text Available Los capibaras son los roedores más grandes del mundo, sin embargo, no se han realizado estudios genético poblacionales exhaustivos con ellos. En el presente trabajo se analizó la estructura genética de una manada de 31 capibaras (Hydrochoerus hydrochaeris muestreada en Hato Corozal, Departamento de Casanare en los Llanos Orientales de Colombia, mediante cinco marcadores microsatelitales. La diversidad genética se determinó en 0.61 y un número promedio de alelos de 5.2, lo cual se puede considerar medio-bajo para este tipo de marcadores. De los cinco marcadores empleados, tres mostraron proporciones genotípicas en concordancia con lo esperado en equilibrio Hardy-Weinberg, mientras que un marcador mostró un exceso significativo de homocigotos y otro un exceso significativo de heterocigotos. No se encontraron diferencias significativas para esos cinco marcadores entre machos y hembras de la manada muestreada. La aplicación de diferentes procedimientos para detectar posibles cambios demográficos históricos (expansiones poblacionales o cuellos de botella mostró claramente que la población analizada ha pasado por un cuello de botella extremadamente fuerte en épocas recientes. La limitada variabilidad genética encontrada y la fuerte evidencia de que la manada estudiada ha pasado por un cuello de botella reciente es probablemente el resultado de la cacería ilegal.Genetic structure of a group of capybaras, Hydrochoerus hydrochaeris (Rodentia: Hydrocheridae in the Colombian Eastern Llanos. The capybaras are the biggest rodents in the world but, however, there are not extensive population genetics studies on them. In the current work, we studied the genetic structure of a troop of 31 capybaras (Hydrochoerus hydrochaeris sampled in Hato Corozal, Casanare Department at the Colombian Eastern Llanos, by means of five microsatellite markers. The gene diversity was 0.61 and the average allele number was 5.2, which is a medium-low level for

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

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    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.

  7. 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”.

  8. 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.

  9. 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.

  10. 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.

  11. Functional differentiation of trailing and leading forelimbs during locomotion on the ground and on a horizontal branch in the European red squirrel (Sciurus vulgaris, Rodentia).

    Science.gov (United States)

    Schmidt, André

    2011-06-01

    Mammalian locomotion is characterized by the frequent use of in-phase gaits in which the footfalls of the left and right fore- or hindlimbs are unevenly spaced in time. Although previous studies have identified a functional differentiation between the first limb (trailing limb) and the second limb (leading limb) to touch the ground during terrestrial locomotion, the influence of a horizontal branch on limb function has never been explored. To determine the functional differences between trailing and leading forelimbs during locomotion on the ground and on a horizontal branch, X-ray motion analysis and force measurements were carried out in two European red squirrels (Sciurus vulgaris, Rodentia). The differences observed between trailing and leading forelimbs were minimal during terrestrial locomotion, where both limbs fulfill two functions and go through a shock-absorbing phase followed by a generating phase. During locomotion on a horizontal branch, European red squirrels reduce speed and all substrate reaction forces transmitted may be due to the reduction of vertical oscillation of the center of mass. Further adjustments during locomotion on a horizontal branch differ significantly between trailing and leading forelimbs and include limb flexion, lead intervals, limb protraction and vertical displacement of the scapular pivot. Consequently, trailing and leading forelimbs perform different functions. Trailing forelimbs function primarily as shock-absorbing elements, whereas leading forelimbs are characterized by a high level of stiffness. This functional differentiation indicates that European red squirrels 'test' the substrate for stability with the trailing forelimb, while the leading forelimb responds to or counteracts swinging or snapping branches. Copyright © 2011 Elsevier GmbH. All rights reserved.

  12. Hábitos alimenticios de la ardilla Sciurus variegatoides (Rodentia: Sciuridae en la Península de Nicoya, Costa Rica

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    Javier Monge

    2006-06-01

    Full Text Available Se determinaron los componentes de la dieta de la ardilla Sciurus variegatoides atrirufus en un área agrícola de la Península de Nicoya, Costa Rica (9º47’ N, 84º56’ W, correspondiente a las zonas de vida Bosque Húmedo Premontano Transición a Basal y Bosque Seco Tropical. Al analizar el contenido estomacal de 120 ardillas, entre febrero de 1987 y enero de 1988, se determinó que los alimentos más importantes fueron el coco (Cocos nucifera, el almendro (Terminalia catappa y el malinche (Delonix regia. Hubo diferencias en el tipo de alimento según la edad. Los adultos consumieron más el coco y los jóvenes el almendro, lo cual se explica por las características del fruto, así como por la arquitectura y acceso al árbol; el almendro aporta mejores condiciones de protección y un recurso alimenticio más accesible, por lo que fue mejor aprovechado por los individuos jóvenes.Feeding habits of the squirrel Sciurus variegatoides (Rodentia: Sciuridae in the Nicoya Peninsula, Costa Rica. Food items consumed by the squirrel Sciurus variegatoides atrirufus were determined in an agricultural setting in the Nicoya Península (9º47’ N, 84º56’ W, Costa Rica, where two life zones (Premontane Moist Forest Basal Belt Transition, and Tropical Dry Forest predominate. By analyzing the gut contents of 120 squirrels, from February 1987 through January 1988, it was determined that coconut (Cocos nucifera, indian almond (Terminalia catappa and flamboyant (Delonix regia were the most common dietary items. There were differences in food consumption according to age: adults preferred coconut, whereas young individuals preferred almond. This finding can be explained in terms of fruit characteristics, as well as tree architecture and accessibility for squirrels; almendro trees provide higher protection and a more accessible food resource, so that it was better used by young individuals. Rev. Biol. Trop. 54(2: 681-686. Epub 2006 Jun 01.

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

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    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

  14. Experimental heteroxenous cycle of Lagochilascaris minor Leiper, 1909 (Nematoda: Ascarididae in white mice and in cats

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    Gregorio S. Volcan

    1992-12-01

    Full Text Available Reports of natural infections of sylvatic carnivores by adult worms of species similar to Lagochilascaris minor in the Neotropical region led to attempts to estabilish experimental cycles in laboratory mice and in cats. Also, larval development was seen in the skeletal muscle of an agouti (Dasyprocta leporina infected per os with incubated eggs of the parasite obtained from a human case. In cats, adult worms develop and fertile eggs are expelled in the feces: in mice, larval stages of the parasite develop, and are encapsulate in the skeletal muscle, and in the adipose and subcutaneous connective tissue. From our observations, we conclude that the larva infective for the mouse is the early 3rd stage, while for the final host the infective form is the later 3rd stage. A single moult was seen in the mouse, giving rise to a small population of 4th stage larvae, long after the initial infection.

  15. Variaciones nucleotídicas de dos grupos de tepezcuintles, Agouti paca (Rodentia: Agoutidae, en cautiverio provenientes de dos localidades de Yucatán, México

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    Rubén C Montes-Pérez

    2006-09-01

    Full Text Available Estimamos las variaciones nucleotídicas entre dos grupos de tepezcuintles (Agouti paca provenientes de los estados de Campeche y Quintana Roo, México y, dentro de cada grupo. Se colectaron muestras sanguíneas de once A. paca mantenidos en cautiverio. El ADN de leucocitos se utilizó para efectuar la amplificación aleatoria de polimorfismos de ADN (RAPD. Se seleccionaron los iniciadores número tres 5’ -d(GTAGACCCGT-3’ y seis 5’ -d(CCCGTCAGCA-3’ del estuche (Ready.To.Go. RAPD Analysis Beads, Amersham Pharmacia Biotech, porque produjeron un adecuado número de bandas. Los patrones electroforéticos de bandas fueron procesados con el software para análisis filogenético basado en el método de UPGMA para estimar la variación nucleotídica. El árbol filogenético obtenido con el iniciador tres reveló una agrupación dicotómica entre los animales de ambos estados de la Península de Yucatán, con un valor de divergencia de 1.983 nucleótidos de cada cien. Los animales de Quintana Roo mostraron un agrupamiento con el iniciador seis y, otro grupo más con animales procedentes de Campeche. La variación nucleotídica entre estos dos grupos fue de 2.118 nucleótidos por cada cien. Las variaciones nucleotídicas dentro de los grupos procedentes de ambos estados, para los dos iniciadores, mostraron valores que fluctuaron entre 0.46 y 1.68 nucleótidos de cada cien, lo cual indica que la variación nucleotídica entre los dos grupos de animales es alrededor de dos nucleótidos por cada cien y, dentro de grupos es menor a 1.7 nucleótidos por cada cien.Nucleotidic variations of two captive groups of tepezcuintle, Agouti paca (Rodentia: Agoutidae, from two sites in Yucatan, Mexico. The objective of this work was to estimate the nucleotidic variation between two groups of tepezcuintles (Agouti paca from the states of Campeche and Quintana Roo, Mexico and within members of each group. Blood samples were collected from eleven A. paca kept in

  16. Ecología poblacional del ratón Peromyscus mexicanus (Rodentia: Muridae en el Parque Nacional Volcán Poás, Costa Rica

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    Licidia Rojas Rojas

    2007-12-01

    Full Text Available Se estudió el tamaño poblacional, la proporción de sexos, el peso y el número de adultos e inmaduros de Peromyscus mexicanus en tres sitios, durante 14 meses, en el Parque Nacional volcán Poás, Costa Rica. Se colocaron 30 trampas Sherman en cada sitio, para un estudio de captura-recaptura durante seis días consecutivos de cada mes, desde marzo de 2002 hasta abril de 2003. Se hicieron 2 393 capturas, hallándose en Tierra Fría, además de P. mexicanus, Reithrodontomys creper, R. rodriguezi, Scotinomys teguina y Oryzomys devius (Muridae. En Potrero Grande se capturaron P. mexicanus, R. creper, R. sumichrasti, S. teguina y O. devius. En Canto de las Aves se capturaron P. mexicanus, R. creper, R. rodriguezi y O. devius. El 34.77 % del total de ratones capturados fueron P. mexicanus. Se capturaron en promedio 34 individuos por mes por hectárea en Tierra Fría y 11 en Potrero Grande; en Canto de las Aves sólo se capturaron 4 individuos en todo el muestreo. El tamaño estimado de la población de P. mexicanus no varió mensualmente en Tierra Fría, pero si en Potrero Grande. No se observó variación en la proporción de sexos en ninguno de los dos sitios. El valor promedio de peso en Tierra Fría fue de 43.83+1.93 g machos 39.29+2.07 g hembras. En Potrero Grande fue 43.54+3.42 g machos y 42.08+3.45 g hembras. En ninguno de los dos sitios se encontraron diferencias en la cantidad de individuos inmaduros a través del tiempo.Population ecology of the mouse Peromyscus mexicanus (Rodentia: Muridae in Poas Volcano National Park, Costa Rica. The Mexican Deer Mouse has been reported as an abundant wild mouse in Costa Rica; nevertheless, it has not been studied as well as other Peromyscus species. Thirty Sherman traps were placed on three habitats during six consecutive days of each month, from March 2002 through April 2003 in three sites of Poás volcano National Park, Costa Rica. A total of 2 393 mice were captured. Other species such as

  17. 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)

    OpenAIRE

    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...

  18. 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

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    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

  19. 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.

  20. Enfermidades de cutias (Dasyprocta aguti criadas em cativeiro diagnosticadas pelo exame anatomopatológico Diseases of agouti (Dasyprocta aguti raised in captivity diagnosed by pathological examination

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    Jael S. Batista

    2010-06-01

    Full Text Available O exame necroscópico é especialmente útil no diagnóstico de enfermidades em animais silvestres. Em muitas ocasiões, as manifestações clínicas não são características como em animais domésticos, sendo frequente a ocorrência de óbitos em animais assintomáticos. Este trabalho objetivou realizar um estudo retrospectivo sobre as doenças de cutias diagnosticadas pelo Laboratório de Patologia Veterinária da Universidade Federal Rural do Semi-Árido, através do exame anatomopatológico no período de 2006 a 2009. Em 32 cutias submetidas à necropsia, as percentagens das enfermidades diagnosticadas foram: morte perinatal pelo complexo inanição/hipotermia (21,6%, urolitíase obstrutiva (6,24%, distocia (6,24%, obstrução do ceco por areia - sablose (6,24%, intussuscepção (3,20%, fecaloma (3,20% e obstrução do esôfago (3,20%. Dezesseis (16 animais permaneceram sem diagnóstico, dos quais nove (28,48% apresentavam avançado estado autolítico e em sete (21,60% não foram observadas lesões macro e microscópicas compatíveis com nenhuma enfermidade. Este artigo apresenta relatos de doenças ainda não descritas em cutias e seus resultados poderão produzir literatura sobre os aspectos patológicos destas enfermidades nessa espécie.Necroscopic examination is remarkably useful to diagnose wild animal's diseases. In several occasions the clinical signs are not charactheristic as in domestic animals and the occurrence of death in asymptomatic animals is frequent. Thus, the present work aimed to accomplish a retrospective study on agouti diseases diagnosed by pathological examination in the Laboratory of Veterinary Pathology, Federal Rural University of the Semi-arid, through January 2006 to December 2006. In 32 agoutis submitted to the necropsy, the percentage of diagnosed diseases was: perinatal death due hypothermia/ inanition complex (21.6%, obstructive urolithiasis (6.24%, dystocia (6.24%, cecum sablosis (6.24%, intussusceptions (3.20%, fecaloma (3.20% and esophagus obstruction (3.20%. A total of 16 (50.08% animals remained undiagnosed in which nine (28.48% showed advanced autolysis and seven (21.60% agouti had none macroscopic or microscopic lesions compatible with any disease. The present article presents reports of some diseases not yet diagnosed in agoutis and these results may produce literature review about the pathologic aspects of these diseases in this species.

  1. Ecological Relationships of Meso-Scale Distribution in 25 Neotropical Vertebrate Species

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    Michalski, Lincoln José; Norris, Darren; de Oliveira, Tadeu Gomes; Michalski, Fernanda

    2015-01-01

    Vertebrates are a vital ecological component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services they continue to be threatened by anthropogenic impacts throughout the Amazon. Here we use a standardized, regularly spaced arrangement of camera traps within 25km2 to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. We examined seasonal differences in the per species encounter rates (number of photos per camera trap and number of cameras with photos). Generalized linear models (GLMs) were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river) on the number of photos per species and on functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (Panthera onca) and Puma (Puma concolor)] and their prey. A total of 649 independent photos of 25 species were obtained from 1,800 camera trap days (900 each during wet and dry seasons). Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons for only three species (Mazama americana, Dasyprocta leporina and Myoprocta acouchy) all of which were photographed more (3 to 10 fold increase) during the wet season. Mazama americana was the only species where a significant difference was found in occupancy, with more photos in more cameras during the wet season. For most groups and species variation in the number of photos per camera was only explained weakly by the GLMs (deviance explained ranging from 10.3 to 54.4%). Terrestrial birds (Crax alector, Psophia crepitans and Tinamus major) and rodents (Cuniculus paca, Dasyprocta leporina and M. acouchy) were the notable exceptions, with our GLMs significantly explaining variation in the distribution of all species

  2. Ecological relationships of meso-scale distribution in 25 neotropical vertebrate species.

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    Lincoln José Michalski

    Full Text Available Vertebrates are a vital ecological component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services they continue to be threatened by anthropogenic impacts throughout the Amazon. Here we use a standardized, regularly spaced arrangement of camera traps within 25km2 to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. We examined seasonal differences in the per species encounter rates (number of photos per camera trap and number of cameras with photos. Generalized linear models (GLMs were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river on the number of photos per species and on functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (Panthera onca and Puma (Puma concolor] and their prey. A total of 649 independent photos of 25 species were obtained from 1,800 camera trap days (900 each during wet and dry seasons. Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons for only three species (Mazama americana, Dasyprocta leporina and Myoprocta acouchy all of which were photographed more (3 to 10 fold increase during the wet season. Mazama americana was the only species where a significant difference was found in occupancy, with more photos in more cameras during the wet season. For most groups and species variation in the number of photos per camera was only explained weakly by the GLMs (deviance explained ranging from 10.3 to 54.4%. Terrestrial birds (Crax alector, Psophia crepitans and Tinamus major and rodents (Cuniculus paca, Dasyprocta leporina and M. acouchy were the notable exceptions, with our GLMs significantly explaining variation in the distribution of all

  3. Ecological relationships of meso-scale distribution in 25 neotropical vertebrate species.

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    Michalski, Lincoln José; Norris, Darren; de Oliveira, Tadeu Gomes; Michalski, Fernanda

    2015-01-01

    Vertebrates are a vital ecological component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services they continue to be threatened by anthropogenic impacts throughout the Amazon. Here we use a standardized, regularly spaced arrangement of camera traps within 25km2 to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. We examined seasonal differences in the per species encounter rates (number of photos per camera trap and number of cameras with photos). Generalized linear models (GLMs) were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river) on the number of photos per species and on functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (Panthera onca) and Puma (Puma concolor)] and their prey. A total of 649 independent photos of 25 species were obtained from 1,800 camera trap days (900 each during wet and dry seasons). Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons for only three species (Mazama americana, Dasyprocta leporina and Myoprocta acouchy) all of which were photographed more (3 to 10 fold increase) during the wet season. Mazama americana was the only species where a significant difference was found in occupancy, with more photos in more cameras during the wet season. For most groups and species variation in the number of photos per camera was only explained weakly by the GLMs (deviance explained ranging from 10.3 to 54.4%). Terrestrial birds (Crax alector, Psophia crepitans and Tinamus major) and rodents (Cuniculus paca, Dasyprocta leporina and M. acouchy) were the notable exceptions, with our GLMs significantly explaining variation in the distribution of all species

  4. Electrocardiogram assessment in non-anaesthetized clinically healthy agouti (Dasyprocta primnolopha, Wagler 1831

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    Anaemilia das N. Diniz

    2013-12-01

    Full Text Available The agouti is one of the most intensely hunted species throughout the Amazon and the semiarid regions of north-eastern Brazil. Considering the current tendency of wild animal management in captivity, the objective of this study was to determine heart reference values for agouti raised in captivity, based on electrocardiographic assessments (ECG. Adult agouti were selected without clinical signs of heart disease (n=30. The animals were restrained physically and then the ECG was performed. Standardized measurements were taken to establish the statistical analysis of the data. Analysis of the QRS complex showed values compatible with previous reports in peer animals and the limited data available for other wild and exotic species, except for the T wave that showed similar amplitude to the R wave in all the animals studied. The data obtained provided the first reference values for ECG tracings in agouti, contributing to a better understanding of heart electrophysiology in identifying myocardial pathology in these animals.

  5. Arterial vascularization of the brain of the agouti (Dasyprocta aguti Linnaeus, 1766

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    Roberto Sávio Bessa da Silva

    2016-04-01

    Full Text Available The agouti, a rodent that is geographically distributed throughout South America, is greatly valued for its meat. This paper describes the arterial vascularization of the base of the agouti’s brain, characterizing behavior, and arterial origin and distribution. Ten animals from the Center for the Multiplication of Wild Animals (CEMAS/UFERSA were used and the study was approved by SISBIO (report number 32413- 1 and the Ethics Committee on Animal Use (CEUA/UFERSA (protocol 02/2010. After euthanasia, the animals were incised in the thoracic cavity by an injection of red-stained Neoprene latex 650 and the skulls were subsequently opened. The brains were extracted from the skulls for ventral surface analysis and then fixed in an aqueous 10% formaldehyde solution. The agouti’s arterial vascularization of the brain has two main components, namely the carotid and vertebrobasilar systems. The agouti’s carotid system accounts for vascularization of almost the entire forebrain, while the vertebrobasilar system accounts for vascularization of almost the entire posterior brain (medulla oblongata, pyramid, trapezoid body, cerebellum, bridge, and part of the third caudal section of the forebrain through the caudal cerebral arteries originating from the terminal branches of the basilar artery. The main arteries on the brain surface include the basilar artery, which is unique, and the arterial pairs, specifically the vertebral arteries, cerebellar caudal arteries, trigeminal artery, rostral cerebellar artery, basilar terminal branch artery, cerebral caudal artery, communicating caudal branch of the cerebral carotid artery, cerebral carotid artery, communicating branch rostral cerebral carotid artery, choroidal rostral artery, medial branch of the communicating branch rostral artery, internal ophthalmic artery, middle cerebral artery, and rostral cerebral artery.

  6. Placentation in the capybara (Hydrochaerus hydrochaeris), Agouti (Dasyprocta aguti) and paca (Agouti paca).

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    Miglino, M A; Carter, A M; dos Santos Ferraz, R H; Fernandes Machado, M R

    2002-05-01

    Placentae of three hystricimorph rodents--capybara, agouti and paca--were examined by conventional histology, immunohistochemistry for cytokeratin and vimentin, and TUNEL staining. The placentae were divided into lobules of labyrinthine syncytium separated by interlobular and marginal trophoblast. The subplacenta comprised cytotrophoblasts, supported on lamellae of allantoic mesoderm, and syncytiotrophoblast. The central excavation was still apparent in the definitive placenta of capybara. In agouti and paca, the decidua of the junctional zone formed a mesoplacenta comprising a capsule and a pedicle. Towards term the pedicle formed a tenuous attachment between placenta and uterine wall comprising a few maternal vessels surrounded by degraded tissue. In paca placenta, it was shown by TUNEL staining that breakdown of this tissue occurred by apoptosis. The visceral yolk sac was highly villous and, in agouti, the yolk sac villi were extremely long. Lateral to its attachment to the placenta, the fetal surface was covered with non-vascular yolk sac endoderm. A layer of spongiotrophoblast cells was interposed between the endoderm and the marginal trophoblast.

  7. Ocular comparative anatomy of the family Rodentia.

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    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. Seed predation by mammals in forest fragments in Monteverde, Costa Rica.

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    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.

  10. Morphology of the male agouti accessory genital glands (Dasyprocta prymnolopha Wagler, 1831 Morfologia das glândulas genitais acessórias em cutias (Dasyprocta prymnolopha Wagler, 1831

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    Danilo J. Ayres de Menezes

    2010-09-01

    Full Text Available The morphology of the accessory genital glands of the male agouti was studied in twenty-three animals that were raised in captivity. Twenty animals had their genital glands dissected in situ for macroscopic description. The samples of each gland were recovered, embedded in paraffin, sliced and stained by Hematoxylin-Eosin technique. It was founded four pairs of glands: the vesicular glands, the coagulating glands, the prostate and the bulbourethral glands. Histological characteristics of the vesicular, coagulating and prostate glands showed similar morphology, within the pseudostratified columnar epithelium. The tubulo-alveolar type of the bulbourethral glands showed a lack of connective tissue among the tubules, a small amount of red stained presented it the cytoplasm, and the presence of vacuoles in the tissue. This study concluded that the agouti showed to have similar morphological aspect described in the others species of rodents.A morfologia das glândulas genitais acessórias de cutias foram estudados em 23 animais criados em cativeiros. Vinte animais tiveram suas glândulas genitais dissecadas in situ para as descrições macroscópicas. Para o estudo microscópico foram utilizados três animais. Os fragmentos de cada glândula foram embebidos em parafina, seccionados e corados em hematoxilina e eosina. Foram encontrados quatro pares de glândulas: vesiculares, coaguladoras, próstata e bulbouretrais. As características histológicas da glândula vesicular, coaguladora e próstata mostraram morfologia similar, com epitélio colunar pseudoestratificado. O tipo tuboalveolar da glândula bulbouretral mostrou uma deficiência de tecido conjuntivo, citoplasma pouco corado e presença de vacúolos. Este estudo concluiu que a cutia apresenta as mesmas características morfológicas das glândulas genitais acessórias encontradas em roedores.

  11. Desempenho de cutias (Dasyprocta prymnolopha criadas em cativeiro do nascimento até o desmame em Teresina, Piauí Performance of agouti (Dasyprocta prymnolopha bred in captivity according to sex and parturition in Teresina, Piauí

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    João Batista Lopes

    2004-12-01

    Full Text Available Objetivou-se avaliar a influência do sexo e do tipo de parto (simples ou duplo sobre peso, comprimento corporal, perímetro torácico ao nascer e ao desmame de cutias, bem como o ganho de peso total e o ganho médio diário, em busca de subsídios que contribuam para a preservação e a exploração racional desses animais. Foram avaliados 41 animais (26 machos e 15 fêmeas, em delineamento experimental inteiramente casualizado em esquema fatorial 2x2, associando-se os tratamentos: sexo (macho, fêmea e tipo de parto (duplo e simples. O peso médio, o perímetro torácico médio, o comprimento corporal dos filhotes ao nascer para, machos e fêmeas, foram de 147,62 g e 146,25 g; 12,26 cm e 12,17 cm; 19,91 cm e 19,39 cm, respectivamente. Para as mesmas variáveis, os valores ao desmame para machos e fêmeas foram 481,92 g e 509,33 g; 17,12 cm e 16,85 cm; 30,07 cm e 30,42 cm, respectivamente. Não houve diferença significativa entre os parâmetros avaliados, quando comparados ao sexo e ao tipo de parto (simples ou duplo. Concluiu-se que o peso de filhotes de cutia ao nascer e ao desmame não tem relação com o sexo e o tipo de parto; o peso médio, o comprimento corporal e o perímetro torácico de filhotes de cutia ao nascer e ao desmame, respectivamente, são, para ambos os sexos, em torno de 145 g e 500 g, 20 e 30 cm e 12 e 17 cm; o ganho de peso médio diário do nascer ao desmame é de 7,76 g.This experiment was carried out to evaluate the effect of sex and parturition type (simple or double on live weight, body length, thoracic diameter at birth and at weaning of agouti, as well as total weight gain and daily mean weight gain, to obtain subsidies that contribute to preservation and rational exploration of these animals. Fourty-one animals (26 males and 15 females were allotted to a completely randomized a design. Animal weight, thoracic diameter and body length of agouti at birth, for males and females, were respectively: 147.62 g and 146.25 g; 12.26 cm and 12.17 cm; 19.91 cm and 19.39 cm. For the same variables, the values at wean for males and females were, respectively: 481.92 g and 509.33 g; 17.12 cm and 16.85 cm; 30.07 cm and 30.42 cm. No significant difference among the studied variables was observed, when compared to the sex and parturition type (simple or double. It was concluded that the variables studied of of agouti at birth and at weaning were affected neither by sex and nor by parturition type; animal weight, body length and thoracic diameter of agouti at birth and weaning were around 145 g and 500 g, 20 and 30 cm and 12 and 17 cm, respectively; and daily mean weight gain from to birth to weaning is about 7.76 g for both sexes.

  12. Isolation, expansion and differentiation of cellular progenitors obtained from dental pulp of agouti (Dasyprocta prymnolopha Wagler, 1831

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    Yulla K.P. de Carvalho

    2015-06-01

    Full Text Available Abstract: The study aimed to isolate, expand, differentiate and characterize progenitor cells existent in the dental pulp of agouti. The material was washed with PBS solution and dissociated mechanically with the aid of a scalpel blade on plates containing culture medium D-MEM/F-12, and incubated at 5% CO2-37⁰C. The growth curve, CFU assay, osteogenic/adipogenic differentiation and characterization were obtained from the isolation. The cells began to be released from the explant tissue around the 7th day of culture. By day 22 of culture, cells reached 80% confluence. At the UFC test, 81 colonies were counted with 12 days of cultivation. The growth curves before and after freezing showed a regular growth with intense proliferation and clonogenic potential. The cell differentiation showed formation of osteoblasts and fat in culture, starting at 15 days of culture in a specific medium. Flow cytometry (FACs was as follows: CD34 (positive, CD14 (negative, CD45 (negative, CD73 (positive, CD79 (negative, CD90 (positive, CD105 (positive, demonstrating high specificity and commitment of isolated cells with mesenchymal stem cells strains. These results suggest the existence of a cell population of stem cells with mesenchymal features from the isolated tissue in the explants of agouti dental pulp, a potential model for study of stem cell strains obtained from the pulp tissue.

  13. Thoracic and heart biometrics of non-anesthetized agouti (Dasyprocta primnolopha Wagler, 1831 measured on radiographic images

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    Anaemilia das N. Diniz

    2013-03-01

    Full Text Available The agouti is a species intensively hunted throughout the Amazon and the semi-arid regions of northeastern Brazil. Considering the current trend in conservation management of wild species, the aim of this study was to determine the morphometric reference to the heart of agouti raised in captivity, based on thoracic and cardiac measurements in these animals. Thirty adult agoutis, 1 to 3 years of age, without clinical signs of cardiac disease were selected. The animals were physically restrained and radiographies in laterolateral (LL and ventrodorsal (VD recumbence were produced. The following measures were taken: the apicobasilar length of the heart (at the most cranial height of the Carina region to the heart apex (AB, maximum width of the heart perpendicular to AB (CD, heart inclination angle (AIC, trachea inclination angle (AIT, distance from the right heart wall (DPTd, distance from the left heart wall (DPTe and vertical depth of the thorax, and the ventral face of the vertebral column to the dorsal border of the sternum at the level of the trachea bifurcation (H. The ratios between AB/CD, AB/H and CD/H were also analyzed. To calculate the vertebral heart scale (VHS, the AB and CD measurements were laid over the thoracic vertebra starting at T4. Radiographic evaluation showed values consistent with those reported in small animals and some wild and exotic species. The main biometric values in the chest cavity and heart of agouti are arranged as follows: (1 The ratios between AB/H ratio and CD/H were not sensitive for identifying heart increases (p>0.05, while the ratio AB/CD was more sensitive in this identification (p<0.05; (2 AIC: 21.2±6.4º (mean between male and famale; (3 AIT for males and females: 9.93±3.23° and 8.4±3.94°; (4 DPTd and DPTe for males: 0.97±0.40cm and 0.7±0.30cm; (5 DPTd and DPTe for females: 1.12±0.42cm and 01.02±0.43cm; (6 VHS for males and females: 7.75±0.48v e 7.61±0.34v; (7 The caudal vena cava (CVC was visualized dorsal-cranially and located right of the midline. The data obtained allowed the acquisition of the first reference values for biometry of the heart of agoutis, contributing to better understanding of cardiac morphology and identification of cardiomyopathy in these animals.

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

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    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.

  15. 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...

  16. 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.

  17. Chromosomal evolution in small mammals (Insectivora, Chiroptera, Rodentia

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    Jan Zima

    2000-09-01

    Full Text Available Abstract Extensive descriptive, comparative, and experimental research on the chromosomes of natural populations of small mammals has been conducted in the last 50 years. These studies have revealed a surprisingly large amount of karyotypic variation within and between individuals, populations, species, and higher taxa. In the Palaearctic region, the karyotypes of 80 to 90% of the species of insectivores, bats and rodents have already been described, and almost all European species belonging to these orders have been examined. More than 40 cryptic species of small mammals with a unique karyotype have been described in the Palaearctic region, including 24 species in Europe. A polymorphic or polytypic karyotype was found in 118 Palaearctic and 42 European species. This high degree of intraspecific karyotypic variation has resulted in problems in the naming of various chromosomal races, since the subspecies is clearly not the appropriate category for this purpose. The driving forces of karyotypic evolution may be found either in selection or drift acting at the organismal level, or in the internal processes occurring within the cell. The forces acting at the organismal level are based on either negative heterosis of chromosomal rearrangements or on the altered pattern of gene expression resulting from karyotypic repatterning. Little evidence for the direct adaptive nature of chromosomal alterations has been presented up to now and the significance of this factor remains unclear. Chromosomal change is, however, obviously correlated with speciation and divergent evolution, even if karyotypic alterations in certain lineages need not be directly related to the formation of a reproductive barrier. Chromosomal studies are still an important tool to record and describe biological diversity, and often represent a simple and indispensable method for identification of various taxa.

  18. 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.

  19. 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.

  20. 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).

  1. 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…

  2. Mesoamerican tree squirrels evolution (Rodentia: Sciuridae): a molecular phylogenetic analysis.

    Science.gov (United States)

    Villalobos, Federico; Gutierrez-Espeleta, Gustavo

    2014-06-01

    The tribe Sciurini comprehends the genera Sciurus, Syntheosiurus, Microsciurus, Tamiasciurus and Rheinthrosciurus. The phylogenetic relationships within Sciurus have been only partially done, and the relationship between Mesoamerican species remains unsolved. The phylogenetic relationships of the Mesoamerican tree squirrels were examined using molecular data. Sequence data publicly available (12S, 16S, CYTB mitochondrial genes and IRBP nuclear gene) and cytochrome B gene sequences of four previously not sampled Mesoamerican Sciurus species were analyzed under a Bayesian multispecies coalescence model. Phylogenetic analysis of the multilocus data set showed the neotropical tree squirrels as a monophyletic clade. The genus Sciurus was paraphyletic due to the inclusion of Microsciurus species (M. alfari and M. flaviventer). The South American species S. aestuans and S. stramineus showed a sister taxa relationship. Single locus analysis based on the most compact and complete data set (i.e. CYTB gene sequences), supported the monophyly of the South American species and recovered a Mesoamerican clade including S. aureogaster, S. granatensis and S. variegatoides. These results corroborated previous findings based on cladistic analysis of cranial and post-cranial characters. Our data support a close relationship between Mesoamerican Sciurus species and a sister relationship with South American species, and corroborates previous findings in relation to the polyphyly of Microsciurus and Syntheosciurus paraphyly.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. PESO PÓS-PARTO, FREQÜÊNCIA E PREVALÊNCIA DO TIPO DE PARTO DE CUTIAS (Dasyprocta sp CRIADAS EM CATIVEIRO

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    Maria Acelina Martins de Carvalho

    2006-10-01

    Full Text Available A pesquisa objetivou avaliar parâmetros de desenvolvimento de cutias, buscando fornecer dados para contribuir com a seleção, o melhoramento genético e formas adequadas de manejo para estes animais. Foram observados o peso pós-parto, freqüência e a prevalência do tipo de parto em função da época do ano em 33 fêmeas. Constatou-se que não houve interação entre época do ano e tipo de parto (P>0,05. O peso médio pós-parto foi de 2,24 Kg e 2,39 Kg, para o período de janeiro a dezembro, respectivamente, não apresentando diferença significativa para esta variável (P>0,05. Com relação ao tipo de parto, as cutias com parto simples apresentaram peso médio de 2,32 Kg e as com parto duplo 2,38 Kg, não sendo estes valores significativamente diferentes entre si (P>0,05. Concluiu-se que o peso da cutia fêmea pós-parto, a freqüência e o tipo de parto (simples e duplos não sofrem influência da época do ano e que a cutia em cativeiro se comporta como poliéstrica contínua. PALAVRAS-CHAVE: Cutia, peso pós-parto, prevalência, tipo de parto.

  11. Estudo morfológico e morfométrico do ovário de cutias (Dasyprocta aguti, Linnaeus, 1766

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    Mônica Marcos de Almeida

    2003-01-01

    Full Text Available Foram estudados 24 ovários pertencentes a 13 cutias adultas (em dois exemplares pesquisou-se apenas o ovário esquerdo, sendo 7 gestantes e 6 não gestantes, provenientes do Núcleo de Estudos e Preservação de Animais Silvestres da Universidade Federal do Piauí. Os órgãos foram observados in loco para descrição de sua topografia, mensurados, submetidos a cortes histológicos e observados em Microscópio Óptico. Os ovários apresentam-se de forma elipsóide, achatados dorsoventralmente, situando-se na região sub-lombar, caudalmente aos rins, com pequenas áreas transparentes em sua superfície externa. A margem mesovárica e a face lateral estão cobertas pelo mesossalpinge (bolsa ovárica. O ovário direito, apresenta em média: peso - 0,082g; comprimento - 0,83cm; largura - 0,49cm e espessura - 0,24cm; o ovário esquerdo: peso - 0,058g; comprimento - 0,74cm; largura - 0,45cm e espessura - 0,23cm. Histologicamente, constam de epitélio de revestimento cúbico simples, córtex periférico e medula central, constituída basicamente por tecido conjuntivo frouxo entremeado por vasos sangüíneos. Nas fêmeas gestantes foram observados de dois a três grandes corpos lúteos centrais e muitos outros menores periféricos; nas não gestantes os corpos lúteos são menores e mais numerosos. O córtex é rico em tipos celulares de natureza conjuntiva e em folículos em diferentes estágios de amadurecimento, os quais migram da margem mesovárica para a extremidade tubárica à medida que aumentam de tamanho. Conclui-se que os ovários da cutia, macro e microscopicamente, seguem o padrão observado nos demais roedores sexualmente ativos.

  12. Water availability not fruitfall modulates the dry season distribution of frugivorous terrestrial vertebrates in a lowland Amazon forest.

    Science.gov (United States)

    Paredes, Omar Stalin Landázuri; Norris, Darren; Oliveira, Tadeu Gomes de; Michalski, Fernanda

    2017-01-01

    Terrestrial vertebrate frugivores constitute one of the major guilds in tropical forests. Previous studies show that the meso-scale distribution of this group is only weakly explained by variables such as altitude and tree basal area in lowland Amazon forests. For the first time we test whether seasonally limiting resources (water and fallen fruit) affect the dry season distribution in 25 species of terrestrial vertebrates. To examine the effects of the spatial availability of fruit and water on terrestrial vertebrates we used a standardized, regularly spaced arrangement of camera-traps within 25km2 of lowland Amazon forest. Generalized linear models (GLMs) were then used to examine the influence of four variables (altitude, distance to large rivers, distance to nearest water, and presence vs absence of fruits) on the number of photos on five functional groups (all frugivores, small, medium, large and very large frugivores) and on seven of the most abundant frugivore species (Cuniculus paca, Dasyprocta leporina, Mazama americana, Mazama nemorivaga, Myoprocta acouchy, Pecari tajacu and Psophia crepitans). A total of 279 independent photos of 25 species were obtained from 900 camera-trap days. For most species and three functional groups, the variation in the number of photos per camera was significantly but weakly explained by the GLMs (deviance explained ranging from 6.2 to 48.8%). Generally, we found that the presence of water availability was more important than the presence of fallen fruit for the groups and species studied. Medium frugivores, large-bodied frugivores, and two of the more abundant species (C. paca and P. crepitans) were recorded more frequently closer to water bodies; while none of the functional groups nor the most abundant species showed any significant relationship with the presence of fallen fruit. Two functional groups and two of the seven most common frugivore species assessed in the GLMs showed significant results with species

  13. Rhizobium grahamii sp. nov., from nodules of Dalea leporina, Leucaena leucocephala and Clitoria ternatea, and Rhizobium mesoamericanum sp. nov., from nodules of Phaseolus vulgaris, siratro, cowpea and Mimosa pudica.

    Science.gov (United States)

    López-López, Aline; Rogel-Hernández, Marco A; Barois, Isabelle; Ortiz Ceballos, Angel I; Martínez, Julio; Ormeño-Orrillo, Ernesto; Martínez-Romero, Esperanza

    2012-09-01

    Two novel related Rhizobium species, Rhizobium grahamii sp. nov. and Rhizobium mesoamericanum sp. nov., were identified by a polyphasic approach using DNA-DNA hybridization, whole-genome sequencing and phylogenetic and phenotypic characterization including nodulation of Leucaena leucocephala and Phaseolus vulgaris (bean). As similar bacteria were found in the Los Tuxtlas rainforest in Mexico and in Central America, we suggest the existence of a Mesoamerican microbiological corridor. The type strain of Rhizobium grahamii sp. nov. is CCGE 502(T) (= ATCC BAA-2124(T) = CFN 242(T) = Dal4(T) = HAMBI 3152(T)) and that of Rhizobium mesoamericanum sp. nov. is CCGE 501(T) (= ATCC BAA-2123(T) = HAMBI 3151(T) = CIP 110148(T) = 1847(T)).

  14. A survey of hemoparasite infections in free-ranging mammals and reptiles in French Guiana.

    Science.gov (United States)

    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.

  15. Thoracic and heart biometrics of non-anesthetized agouti (Dasyprocta primnolopha Wagler, 1831 measured on radiographic images Biometria torácica e cardíaca de cutias não anestesiadas (Dasyprocta primnolopha Wagler, 1831 mensuradas em imagens radiográficas

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    Anaemilia das N. Diniz

    2013-03-01

    Full Text Available The agouti is a species intensively hunted throughout the Amazon and the semi-arid regions of northeastern Brazil. Considering the current trend in conservation management of wild species, the aim of this study was to determine the morphometric reference to the heart of agouti raised in captivity, based on thoracic and cardiac measurements in these animals. Thirty adult agoutis, 1 to 3 years of age, without clinical signs of cardiac disease were selected. The animals were physically restrained and radiographies in laterolateral (LL and ventrodorsal (VD recumbence were produced. The following measures were taken: the apicobasilar length of the heart (at the most cranial height of the Carina region to the heart apex (AB, maximum width of the heart perpendicular to AB (CD, heart inclination angle (AIC, trachea inclination angle (AIT, distance from the right heart wall (DPTd, distance from the left heart wall (DPTe and vertical depth of the thorax, and the ventral face of the vertebral column to the dorsal border of the sternum at the level of the trachea bifurcation (H. The ratios between AB/CD, AB/H and CD/H were also analyzed. To calculate the vertebral heart scale (VHS, the AB and CD measurements were laid over the thoracic vertebra starting at T4. Radiographic evaluation showed values consistent with those reported in small animals and some wild and exotic species. The main biometric values in the chest cavity and heart of agouti are arranged as follows: (1 The ratios between AB/H ratio and CD/H were not sensitive for identifying heart increases (p>0.05, while the ratio AB/CD was more sensitive in this identification (pA cutia é uma espécie intensamente caçada em toda a Amazônia e nas regiões semi-áridas do Nordeste do Brasil. Considerando a tendência atual em gestão de conservação das espécies selvagens, o objetivo deste estudo foi determinar referências morfométricas para o coração de cutia criadas em cativeiro, com base em medições torácicas e cardíacas desses animais. Foram selecionados 30 cutias adultas, sem sinais clínicos de doença cardíaca, com idade entre 1 a 3 anos. Os animais foram contidos fisicamente e realizadas projeções radiográficas laterolaterais e (LL e ventrodorsais (VD. As seguintes medidas foram tomadas: O comprimento apicobasilar do coração (na altura mais cranial da região carina até o ápice do coração (AB; a largura máxima coração perpendicular a AB (CD; o ângulo de inclinação do cardíaca (AIC; ângulo de inclinação da traquéia (AIT; a distância a partir da parede direita do coração (DPTd; a distância a partir da parede esquerda do coração (DPTe e profundidade vertical do tórax, da face ventral da coluna vertebral até à borda dorsal do esterno, no nível da bifurcação da traqueia (H. As relações entre AB/CD, AB/H e CD/H também foram analisadas. Para calcular o "vertebral heart scale" (VHS, as medidas AB e CD foram colocadas sob as vértebras torácicas a partir de T4. A avaliação radiográfica demonstrou valores consistentes com aqueles relatados em pequenos animais e algumas espécies selvagens e exóticos. Os principais valores biométricos mensurados na cavidade torácica e cardíaca da cutia, estão dispostas da seguinte forma: (1 As relações entre AB/H e CD/H não foram sensíveis para identificar aumento do coração (p> 0,05, enquanto a proporção AB/CD foi mais sensível nesta identificação (p <0,05; (2 AIC: 21,2 ± 6.4º (média entre machos e fêmeas; (3 AIT para machos e fêmeas: 9.93 ± 3.23° and 8.4±3.94°; (4 DPTd e DPTe para os machos: 0,97 ± 0,40 cm e 0,7 ± 0,30, (5 DPTd e DPTe para as fêmeas: 1,12 ± 0,42 e 01,02 ± 0,43; (6 VHS para machos e fêmeas: 7.75±0.48v e 7.61±0.34v; (7 A veia cava caudal (CVC foi visualizada dorso-cranialmente e localizada à direita da linha média. Os dados obtidos permitiram a obtenção dos primeiros valores de referência para a biometria do coração de cutias, contribuindo para uma maior compreensão da morfologia cardíaca e identificação de cardiomiopatia nestes animais.

  16. Efeito das atividades de ecoturismo sobre a riqueza e a abundância de espécies de mamíferos de médio e grande porte na região do Cristalino, Mato Grosso, Brasil Effect of ecotourism activities on richness and abundance of species of medium and large mammals in the Cristalino region, Mato Grosso, Brazil

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    Ednaldo Cândido Rocha

    2012-12-01

    Full Text Available Este estudo foi desenvolvido nas Reservas Particulares do Patrimônio Natural Cristalino (670 ha e Lote Cristalino (6.539 ha e no Parque Estadual Cristalino (184.900 ha. Essas unidades de conservação são contíguas e estão localizadas no extremo centro-norte do estado do Mato Grosso, em locais considerados prioritários para a conservação, em função da alta biodiversidade e endemismos, além da elevada pressão antrópica. Desta forma, este trabalho objetivou conhecer, avaliar e comparar a estrutura das populações de mamíferos de médio e grande porte, em termos de riqueza e abundância das espécies em ambientes sem turismo e com atividades de ecoturismo na região do Cristalino. Para tanto, no período compreendido entre maio de 2008 a fevereiro de 2010 foram amostrados ambientes com floresta primária, os quais apresentavam dois níveis de perturbação antrópica: sem turismo e com atividades de ecoturismo. Os dados foram coletados utilizando a amostragem de distâncias em transecções lineares, que totalizou 468,3 Km percorridos nos períodos diurno e noturno, e registro de pegadas em parcelas previamente preparadas (n = 660 parcelas vistoriadas, além de percursos fluviais no rio Cristalino e buscas aleatórias nos locais onde não ocorriam caminhos. Registros de 37 espécies de mamíferos foram obtidos, sendo 33 de médio e grande porte e quatro de pequeno porte. Não houve diferença estatisticamente significativa na riqueza de espécies dos ambientes sem turismo e com ecoturismo, sendo que a similaridade de espécies entre eles foi alta (88%. No entanto, três táxons apresentaram abundância inferior nos ambientes com turismo: Dasyprocta leporina (Linnaeus, 1766, Mazama spp. e Dasypus kappleri Krauss, 1862. Percebe-se, portanto, que o impacto negativo das atividades de ecoturismo desenvolvidas na área de estudo foi de pequena magnitude, em termos de riqueza e abundância de mamíferos de médio e grande porte. Assim

  17. 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.

  18. 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

  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. Evolución de los filotinos (Rodentia, Muridae en los Andes del Sur Evolution of phyllotines (Rodentia, Muridae in the southern Andes

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    ANGEL E SPOTORNO

    2001-03-01

    Full Text Available La tribu Phyllotini es un grupo avanzado de 46 especies endémicas entre los Muridae de América del Sur que, estando adaptado a sus ambientes xéricos, parece haber tenido el Altiplano Sur como área de diferenciación original (Reig 1986. Esta hipótesis es puesta a prueba examinando la distribución geográfica y los datos citogenéticos de 35 especies, incluyendo la descripción de bandas G de Andinomys edax y Euneomys chinchilloides y su comparación con Phyllotis, bandas AgNOR y FISH para ADNr en siete especies, así como datos de electroforesis de proteínas (118 electroalelos en 12 especies y de secuencias del gen para citocromo b en el ADNmt (407 pb en 14 especies. Todos los cariotipos resultaron cromosómicamente distintos, excepto dos en los que no se contó con bandas G. Se encontró una asociación general entre distribución altiplánica de las especies con estados de caracteres ancestrales (cromosomas telocéntricos, 2n altos, posiciones basales en las filogenias basadas en proteínas y secuencias de citocromo b, así como entre distribución no altiplánica y estados derivados. Se documentan aquí distintas combinaciones de brazos cromosómicos tipo Andinomys que se fusionarían para formar cromosomas metacéntricos en Euneomys y Phyllotis, y también una disminución del número de NORes estructurales en Auliscomys respecto de Loxodontomys, rasgos derivados que demuestran una diversificación hacia el sur y otra hacia el norte respectivamente, desde un centro en el Altiplano SurThe tribe Phyllotini is an advanced group of 46 endemic species among the Muridae of South America, that being adapted to its xeric environments, seems to have the Southern Altiplano as its original differentiation area (Reig 1986. This hypothesis is tested by examining the geographic distributions and cytogenetic data from 35 species, including the Andinomys edax and Euneomys chichilloides G band descriptions, its comparison with Phyllotis, AgNOR bands and rDNA FISH in seven species, as well as protein electrophoresis data (118 electro-alleles in 12 species and cytochrome b gen sequences in the mtDNA (407 bp in 14 species. All karyotypes were chromosomically different, except in two cases with unknown G bands. A general association between altiplanic distribution of species with ancestral character states (telocentric chromosomes, high 2n, basal positions in phylogenies based on protein and cytochrome b gene sequences was found, as well as between non-altiplanic distribution with derived states. Different combinations of Andinomys-like chromosomal arms that would have suffered centric fusions to form the metacentric chromosomes of Euneomys and Phyllotis, respectively, are documented here, and also a reduction of the number of structural NOR in Auliscomys compared to Loxodontomys, all derived features showing a diversification to the south and another to the north respectively, from a center in the southern Altiplano

  4. 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

  5. Molecular phylogenies, chromosomes and dispersion in Brazilian akodontines (Rodentia, Sigmodontinae Filogenia molecular, cromossomos e dispersão em akodontinos do Brasil (Rodentia, Sigmodontinae

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    Maria Claudene Barros

    2009-12-01

    Full Text Available A new molecular phylogeny for akodontine rodents from Brazil was proposed. The phylogenetic tree was enriched with the area of occurrence and with information on the karyotype of the samples. Based on this enriched tree, and with a described methodology, hypotheses were proposed on the karyotype and area of occurrence of the ancestors of each Clade. Thus it was possible to discuss hypotheses on chromosome evolution of the group, and on dispersion events from the "area of original differentiation" of akodontines in the Andes. Chromosome evolution started with high diploid numbers (2n=52 and showed a tendency to reduction (until 2n=14 in more recent clades. Independent side-branches of the tree showed 2n reduction and in one case the 2n increased. At least four dispersion events from the Andes down to South-eastern Brazil were proposed. The results should suggest the direction of new studies on comparative karyology.Uma nova filogenia molecular para roedores akodontinos do Brasil é proposta. A árvore filogenética foi enriquecida com a área de ocorrência e com informações sobre o cariótipo das amostras. Baseado nisto, e com a metodologia descrita, foram propostas hipóteses sobre as características do cariótipo e sobre a área de ocorrência dos ancestrais de cada clado. Assim, foi possível discutir hipóteses sobre evolução cromossômica do grupo, e sobre eventos de dispersão a partir da área de diferenciação original dos akodontinos nos Andes. A evolução cromossômica começou com números diplóides altos (2n=52 e mostrou uma tendência a redução (até 2n=14 em clados mais recentes. Ramos independentes da árvore mostraram redução do 2n e num caso aumentou o numero diplóide. Foram propostos pelo menos quatro eventos de dispersão dos Andes até o Brasil Sul-Oriental. Os resultados indicam a direção de novos estudos em cariologia comparada.

  6. 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.

  7. 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...

  8. New Pedetidae (Rodentia: Mammalia from the Mio-Pliocene of Africa

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    Pickford, M.

    2011-12-01

    Full Text Available Pedetidae, or springhares, are represented by a single extant genus (Pedetes and five extinct ones (Parapedetes, Megapedetes, Propedetes, Rusingapedetes and Oldrichpedetes of which the latter two are new. The fossil record of pedetids tends to be scanty, but remains have been found in Southern Africa, East Africa, the Maghreb, the Arabian Peninsula, Turkey and Greece. Most of the localities have yielded only a few isolated teeth. We here describe some of the abundant fossil material from Namibia and Kenya, which throws a great deal of light onthe family.

    Los Pedetidae o liebres saltadoras están representados por un solo género actual (Pedetes y 5 extintos (Parapedetes, Megapedetes, Propedetes, Rusigapedetes y Oldrichpedetes, estos dos últimos son nuevos. El registro fósil de los pedétidos es escaso, pero restos fósiles han sido encontrados en Sudáfrica, África del Este, Magreb, Península Arábiga, Turquía y Grecia. La mayoría de las localidades sólo han suministrado unos pocos dientes aislados. En el presente trabajo describimos parte del abundante material fósil procedente de Namibia y Kenia, que arroja nueva luz al conocimiento de la familia.

  9. 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.

  10. Karyological analysis of Proechimys cuvieri and Proechimys guyannensis (Rodentia, Echimyidae) from central Amazon

    Science.gov (United States)

    e Silva, Carlos Eduardo Faresin; Eler, Eduardo Schmidt; da Silva, Maria Nazareth F.; Feldberg, Eliana

    2012-01-01

    The aim was to characterize the karyotype of rodents of the genus Proechimys from three localities in the central Brazilian Amazon, in the search for new markers that might shed light on our understanding of the taxonomy and evolutionary history of this taxon. Two karyotypes were found, viz., 2n = 28, FN = 46 in individuals from the NRSP (Cuieiras River) and REMAN (Manaus), and 2n = 46, FN = 50 in individuals from the Balbina Hydroelectric Plant. While individuals with the karyotype with 2n = 28 chromosomes were morphologically associated with Proechimys cuvieri, their karyotype shared similarities with those of the same diploid number in two other regions. Although three karyotypes are described for Proechimys cuvieri, no geographic distribution pattern that defined a cline could be identified. Based on the morphological examination of voucher specimens and additional results from molecular analysis, the karyotype with 2n = 46 and FN = 50 could be associated with P. guyannensis. PMID:22481879

  11. 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.

  12. [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.

  13. 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.

  14. 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.

  15. Host evolution in Mastomys natalensis (Rodentia: Muridae): An integrative approach using geometric morphometrics and genetics.

    Science.gov (United States)

    Lalis, Aude; Evin, Allowen; Janier, Marc; Koivogui, Lamine; Denys, Christiane

    2015-11-01

    The commensal rodent Mastomys natalensis is the natural reservoir of Lassa arenavirus (LASV), which causes hemorrhagic fever in West Africa. To study a possible effect of the virus on phenotypic and genotypic variation of its persistently infected host, we compared LASV-positive and non-infected wild-caught M. natalensis. The LASV effects on the phenotypic variation were explored using standard external morphometric measurements, geometric morphometric analyses of the cranial size and shape, and brain case volume. The genetic variability of M. natalensis specimens was assessed using 9 polymorphic microsatellite markers. Independent of sex and age, LASV-infected animals had smaller external body measurements, reproductive organs, skull size and brain case volume. Cranial shape differences between the 2 groups are represented by a lateral constriction of the entire skull. The genetic variability revealed consanguinity only among the LASV-positive rodents. We hypothesize that growth impairment may result in a selective disadvantage for LASV-infected M. natalensis, leading to a preferably commensal lifestyle in areas where the LAVS is endemic and, thereby, increasing the risk of LASV transmission to humans. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  16. 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

  17. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  20. 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.

  1. 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.

  2. Karyotypic and molecular polymorphisms in Ctenomys torquatus (Rodentia: Ctenomyidae): taxonomic considerations.

    Science.gov (United States)

    Fernandes, Fabiano A; Gonçalves, Gislene L; Ximenes, Simone S F; de Freitas, Thales R O

    2009-07-01

    The rodent genus Ctenomys (tuco-tucos) comprises more than 60 described species, and shows extraordinary inter- and intraspecific karyotypic variation. The most widely distributed species of Ctenomys in Brazil is C. torquatus. Although several cytogenetic studies have been done, the karyotypic variability of this species is still poorly known. In this paper we report two new diploid numbers for C. torquatus: 2n = 40 and 2n = 42, both showing AN = 72. The new distribution limits of C. torquatus here reported include localities in the southern, central and western parts of Rio Grande do Sul (RS) State in southern Brazil. The phylogenetic relationship between C. torquatus from Alegrete, RS, and Ctenomys sp. from Corrientes, Argentina, is described by means of mtDNA cytochrome b analysis. Although both entities share similar karyotypes and sperm morphology, these two species are not phylogenetically close.

  3. 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. 

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

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

    OpenAIRE

    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...

  10. Natural Intestinal Protozoa in Rodents (Rodentia: Gerbillinae, Murinae, Cricetinae) in Northwestern Iran

    Science.gov (United States)

    MOHEBALI, Mehdi; ZAREI, Zabiholah; Khanaliha, Khadijeh; KIA, Eshrat Beigom; MOTAVALLI-HAGHI, Afsaneh; DAVOODI, Jaber; REZAEIAN, Tahereh; TARIGHI, Fathemeh; REZAEIAN, Mostafa

    2017-01-01

    Background: Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, Cricetulus migratorius. Methods: This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117), M. musculus (n=63) and C. migratorius (n=24) were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively. Results: About 121(59.3%) of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%), Trichomonas muris 55(27.0%), Chilomastix betencourtti 17 (8.3%), Giardia muris 19(9.3%), Eimeria spp. 46(22.5%), Isospora spp. 4(2%) and Cryptosporidium spp. 1(0.5%) were found from the collected rodents. Microsporidian spores were identified in 63 (31%) out of the 204 collected rodents using aniline blue staining method. Conclusion: Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans. PMID:28979348

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Glaciation effects on the phylogeographic structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae in the southern Andes.

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    R Eduardo Palma

    Full Text Available The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae, the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in Chile: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000-13,000 years ago. Neutrality tests and the "g" parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in southern Temperate Forests (and adjacent areas in Patagonia. From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean Chile using glacial retreats.

  13. Glaciation Effects on the Phylogeographic Structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the Southern Andes

    OpenAIRE

    Eduardo Palma, R.; Dusan Boric-Bargetto; Fernando Torres-Pérez; Cristián E Hernández; Terry L. Yates

    2012-01-01

    The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial dis...

  14. Glaciation effects on the phylogeographic structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the southern Andes.

    Science.gov (United States)

    Palma, R Eduardo; Boric-Bargetto, Dusan; Torres-Pérez, Fernando; Hernández, Cristián E; Yates, Terry L

    2012-01-01

    The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in Chile: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000-13,000 years ago). Neutrality tests and the "g" parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in southern Temperate Forests (and adjacent areas in Patagonia). From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean Chile using glacial retreats.

  15. 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.

  16. 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.

  17. Macroscopic description of thoracic member musculature in Cuniculus paca (Linnaeus, 1766 (Rodentia, Cuniculidae

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    Rodrigo Gomes de Souza

    2017-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2017v30n2p43 Cuniculus paca (Mammalia: Cuniculidae, or ‘paca’ is a rodent species in great demand for its meat, which has led to domestication and development of paca farms in the Brazilian Amazon region, as well as in other states. Despite the growing consumption of paca meat, knowledge on muscle anatomy is still scarce. An anatomical description of paca forelimbs will form the basis for future zootechnical and veterinary studies, enabling the development of sustainable production in the Amazon region, as well as the preservation of the species. We studied forelimb anatomy in four (04 adult pacas from the Caboclinho Project of Catuaba Experimental Farm (UFAC under IBAMA authorization n°509309. Specimens were fixed in 10% formalin and thoracic limbs were dissected, after which anatomical descriptions and photographic records were generated. We found that paca forelimb musculature is similar to that of other groups of domestic animals with regard to the origin and muscle insertion.

  18. 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

    INTRODUCTION: The Laotian rock rat is a relict species in a sister group relationship to hystricognath rodents (Hystricognathi). We asked whether there were similarities in placentation that might reflect this relationship or differences that might cast light on the evolution of Hystricognathi. M...

  19. 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.

  20. 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...

  1. 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.

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

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    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.

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

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    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.

  4. 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.

  5. Records of Coendouichillus (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

    Coendouichillus 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 Coendouichillus 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.

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

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    Tremaine Gregory

    2015-06-01

    Full Text Available 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.

  7. Natural Intestinal Protozoa in Rodents (Rodentia: Gerbillinae, Murinae, Cricetinae in Northwestern Iran

    Directory of Open Access Journals (Sweden)

    Mehdi MOHEBALI

    2017-09-01

    Full Text Available Background: Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, Cricetulus migratorius.Methods: This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117, M. musculus (n=63 and C. migratorius (n=24 were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively.Results: About 121(59.3% of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%, Trichomonas muris 55(27.0%, Chilomastix betencourtti 17 (8.3%, Giardia muris 19(9.3%, Eimeria spp. 46(22.5%, Isospora spp. 4(2% and Cryptosporidium spp. 1(0.5% were found from the collected rodents. Microsporidian spores were identified in 63 (31% out of the 204 collected rodents using aniline blue staining method.Conclusion: Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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. 

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

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    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.

  11. 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.

  12. 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.

  13. 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.

  14. Morphologic characterization of Peromyscus schmidlyi (Rodentia: Cricetidae), an endemic of the Sierra Madre Occidental, Mexico

    National Research Council Canada - National Science Library

    Celia López-González; Diego F. García-Mendoza; Miguel M. Correa-Ramírez

    2013-01-01

    .... We compared and contrasted P. schmidlyi with P. boylii rowleyi and P. spicilegus, morphologically similar and partially sympatric species, and reevaluated the distribution of the 3 species in the Sierra Madre Occidental (SMO) of Mexico. P...

  15. 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

  16. 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.

  17. 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.

  18. Population dynamics of the rat Microryzomys minutus (Rodentia: Muridae in the Venezuelan Andes

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    Daniel R Cabello

    2006-06-01

    Full Text Available The population dynamics of the small forest rice rat Microryzomys minutus, a murid rodent that occurs in the high altitudes of the northern and central Andes, was studied in disturbed and primary environments in a cloud forest of the Venezuelan Andes (Juan Pablo Peñaloza National Park, 8º11’N, 71º49’W. We collected 121 animals (66♀♀ and 55♂♂ between 1995 and 1998, using pitfall traps with formalin. Adult males were heavier than adult females. Relative abundance was much greater in the disturbed environments (over 10 individuals in some periods than in the primary cloud forest: 4-8 individuals. In the disturbed environments, the rats were extremely abundant in the first sampling period, and less frequent afterwards. In the cropland, abundance showed some fluctuations during the study and displayed two small abundance peaks in March-June 1997 and 1998. In the mined area, the rats had irregular fluctuations until March-June 1997 and were not recorded in July-October 1997. The occurrence of this rat in both disturbed and natural habitats confirms the wide ecological tolerance of this species. Rev. Biol. Trop. 54(2: 651-. Epub 2006 Jun 01.Se analizó la dinámica poblacional de las pequeñas ratas silvestres del arroz Microryzomys minutus en ambientes alterados y primarios, en un bosque nublado de los Andes venezolanos. El estudio fue basado en 121 animales (66♀♀ y 55♂♂ recolectados entre 1995 y 1998, usando trampas que contenían formalina. Esta especie está presente en ambos hábitats lo que confirma su amplia tolerancia ecológica. La abundancia poblacional fue mayor en ambientes alterados que en los no alterados. M. minutus presenta dimorfismo sexual en el peso: los machos son más pesados que las hembras.

  19. A new karyotype for the spiny rat Clyomys laticeps (Thomas, 1909 (Rodentia, Echimyidae from Central Brazil

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    Alexandra M. R. Bezerra

    2012-04-01

    Full Text Available Clyomys Thomas, 1916 is a semifossorial rodent genus of spiny rats represented by only one species, C. laticeps, which inhabits the tropical savannas and grasslands of central Brazil and eastern Paraguay. Here we describe a new karyotype of C. laticeps found in populations of Emas National Park, Goiás state, Brazil. The four analyzed specimens had a diploid number (2n of 32 and a fundamental autosome number (FN of 54. Cytogenetic data include conventional staining, CBG and GTG-banding. The karyotype presents 12 meta/submetacentric pairs (1 to 12 and 3 pairs of acrocentrics (13 to 15 with gradual decrease in size. The X chromosome is a medium submetacentric and the Y is a medium acrocentric. The semifossorial habits together with habitat specificity could have contributed to the karyological variations found on this genus.

  20. 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.

  1. 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.

  2. 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.

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

    Science.gov (United States)

    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.

  4. 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.

  5. 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.

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

    Science.gov (United States)

    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.

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

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    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.

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

    Directory of Open Access Journals (Sweden)

    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. 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.

  11. 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

  12. Mandible shape and dwarfism in squirrels (Mammalia, Rodentia): interaction of allometry and adaptation

    Science.gov (United States)

    Hautier, Lionel; Fabre, Pierre-Henri; Michaux, Jacques

    2009-06-01

    Squirrels include several independent lineages of dwarf forms distributed into two ecological groups: the dwarf tree and flying squirrels. The mandible of dwarf tree squirrels share a highly reduced coronoid process and a condylar process drawn backwards. Dwarf flying squirrels on the other hand, have an elongated coronoid process and a well-differentiated condylar process. To interpret such a difference, Elliptic Fourier Transform was used to evaluate how mandible shape varies with dwarfism in sciurids. The results obtained show that this clear-cut difference cannot be explained by a simple allometric relationship in relation with size decrease. We concluded that the retention of anteriorly positioned eye sockets, in relation with distance estimation, allowed the conservation of a well-differentiated coronoid process in all flying species, despite the trend towards its reduction observed among sciurids as their size decreases.

  13. Nest-box occupation by the dormouse Muscardinus avellanarius L. (Rodentia, Myoxidae

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    Alberto Sorace

    1998-12-01

    Full Text Available Abstract The following paper contains data on nest-box occupation by the dormouse in four habitats of the Presidential estate of Castelporziano. Dormouse has been observed inside the nest-boxes in all months of the year and active animals have been repeatedly observed during the winter. These results concord with suggestions that in the Mediterranean area the species occupies nest-boxes also in winter and that it has different yearly rhythms of activity than in northern areas. Except in pine woods, the dormouse was found in nest-boxes of all study habitats. Some results seem to show that competition with hole-nesting passerines heavily affects spring occupation by the dormouse. In spring the Dormouse prefers 'old' nest-boxes, 'new' nest-boxes (i.e. at the first year of placement in a habitat or in a new area are occupied at higher extent from the autumn onwards. Yearly variation in occupation percentages of nest-boxes by the dormouse were also observed.

  14. 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

    2015-01-01

    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. PMID:26250050

  15. 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. 

  16. Modulation of parasitemia and antibody responce to Trypanosoma cruzy by cyclophosphamide in 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, ...

  17. 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.

  18. 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

  19. 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.

  20. 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...

  1. 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.

  2. The conservation status of the tuco-tucos, genus Ctenomys (Rodentia: Ctenomyidae, in southern Brazil

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    FA. Fernandes

    Full Text Available The goal of conservation biology should be related to the preservation of species and also to the evolutionary and ecological processes that were responsible to form them and that are still acting. We review the conservation status of the species of tuco-tuco (Ctenomys torquatus, C. lami, C. minutus, and C. flamarioni from southern Brazil, and relate these data to the geological history of a particular area in that region, the Coastal Plain of the States of Rio Grande do Sul and Santa Catarina. The implications of the data on these species from the Southeastern Brazil are also discussed in relation to the evolution and risk of extinction of these subterranean rodents.

  3. Ontogenetic allometry in the foot size of Oligoryzomys flavescens (Waterhouse, 1837 (Rodentia, Sigmodontinae

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    R. Maestri

    Full Text Available Ontogenetic allometry is the study of how the size or shape of certain structures changes over the course of an animal’s development. In this study, using Huxley's formula of allometric growth (1932, we assessed the changes in the rate of growth of the feet size of the sigmodontine rodent Oligoryzomys flavescens during its ontogeny and compared differences between males and females. We find evidence of a change of polarity during the ontogenetic development of the species, with the presence of positive allometry during pregnancy and negative allometry in adulthood. Moreover, we note the presence of sexual dimorphism in the size of the feet, in which males of the species have a higher rate of growth than females. This growth pattern is positively related to escape from predators in childhood in both sexes and, in adulthood, provides a higher encounter rate of females by males, due to the larger displacement of the latter. We suggest that both the forces of natural selection and sexual selection have acted to shape the evolution of foot size in this species.

  4. Flexibility in the social behavior of captive female capybaras (Mammalia, Rodentia).

    Science.gov (United States)

    Nogueira-Filho, Sérgio L G; Lopes, Pauliene C; Ferreira, Djalma N; Nogueira, Selene S C

    2017-09-01

    Capybara (Hydrochoerus hydrochaeris) lives in stable groups composed of adult males and females with their young. The species shows flexibility in social organization in response to short-term environmental changes, but apparently does not show flexibility in social behavior. To gain insights into mechanisms underlying changes in social relationships, we analyzed the social dominance hierarchy of five captive capybara groups, composed of four to 13 adult females kept in outdoor paddocks ranging from 400 to 4500m(2). In addition, we evaluated the effects of group size and space allowance on two complementary properties of social structure: linearity and steepness. Captive female capybaras exhibit a linear social dominance hierarchy. There was also more predictability in the dominance success- hierarchical steepness - in the dominance hierarchy with a decrease in the space per individual. This variability in response to changing circumstances shows flexibility in capybara's social behavior. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Use of the paca, Cuniculus paca (Rodentia: Agoutidae in the Sierra de Tabasco State Park, Mexico

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    Sonia Gallina

    2012-09-01

    Full Text Available Cuniculus paca is widely distributed throughout the Neotropics. Known as the paca, it is the largest rodent in the Mexican tropical forests, and one of the most used as a subsistence species for its meat. Since colonial times, this species has been subject of an unreported hunting pressure. For this reason, the aim of this work was to describe the use of the paca by the inhabitants of the Sierra de Tabasco State Park (STSP using sampling areas in a matrix of vegetation with different degrees of disturbance, and different types of land use. We included both preserved areas: owing to the presence of large continuous areas of fragmented rainforest and areas that are not preserved, with smaller rainforest fragments and more isolated. To obtain information about paca use, we interviewed 176 people (>18 years old who live in the STSP. All those interviewed had eaten paca meat, and indicated that this species is most frequently observed in the rainforest during the dry season. Hunting and trapping were the most common ways to obtain pacas, rather than gifting or purchasing, and firearms and dogs are used to hunt them. We estimated that these interviewed group had hunted a total of 488 paca in the year prior to the study.Cuniculus paca está ampliamente distribuido en el Neotrópico. El tepezcuintle o paca es el roedor más grande que se encuentra en las selvas tropicales de México. En cuanto a la cacería de subsistencia es una de las especies más buscadas por su carne. Como se desconoce el impacto de esta actividad, se describe el aprovechamiento que le dan las comunidades humanas en el Parque Estatal de la Sierra de Tabasco (PEST. También, se determinaron zonas de muestreo, las cuales se encontraban en una matriz perturbada en menor o mayor grado, con diferentes tipos de uso de suelo. Además, se consideraron zonas conservadas por la presencia continua de grandes extensiones de selvas fragmentadas y las zonas no conservadas por tener fragmentos menores de selvas y estar más aisladas. Para conocer el aprovechamiento que se le da al tepezcuintle se realizaron 176 encuestas a campesinos o pobladores del PEST mayores de 18 años. El 100% de las personas encuestadas dijo conocer al tepezcuintle y haberlo consumido. La sequía fue la época en que significativamente se le observó más en la selva. Las formas de obtención del tepezcuintle que prevalecen son la cacería y el trampeo en contraste con la donación y la compra. Por otro lado, también utilizan armas de fuego y perros para su cacería. Consecuentemente, se estimó que las personas entrevistadas cazaron un total de 488 tepezcuintles en el año.

  6. 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

  7. 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

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

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    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.

  9. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  15. 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.

  16. Efeito das atividades de ecoturismo sobre a riqueza e a abundância de espécies de mamíferos de médio e grande porte na região do Cristalino, Mato Grosso, Brasil

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    Ednaldo Cândido Rocha

    2012-12-01

    Full Text Available Este estudo foi desenvolvido nas Reservas Particulares do Patrimônio Natural Cristalino (670 ha e Lote Cristalino (6.539 ha e no Parque Estadual Cristalino (184.900 ha. Essas unidades de conservação são contíguas e estão localizadas no extremo centro-norte do estado do Mato Grosso, em locais considerados prioritários para a conservação, em função da alta biodiversidade e endemismos, além da elevada pressão antrópica. Desta forma, este trabalho objetivou conhecer, avaliar e comparar a estrutura das populações de mamíferos de médio e grande porte, em termos de riqueza e abundância das espécies em ambientes sem turismo e com atividades de ecoturismo na região do Cristalino. Para tanto, no período compreendido entre maio de 2008 a fevereiro de 2010 foram amostrados ambientes com floresta primária, os quais apresentavam dois níveis de perturbação antrópica: sem turismo e com atividades de ecoturismo. Os dados foram coletados utilizando a amostragem de distâncias em transecções lineares, que totalizou 468,3 Km percorridos nos períodos diurno e noturno, e registro de pegadas em parcelas previamente preparadas (n = 660 parcelas vistoriadas, além de percursos fluviais no rio Cristalino e buscas aleatórias nos locais onde não ocorriam caminhos. Registros de 37 espécies de mamíferos foram obtidos, sendo 33 de médio e grande porte e quatro de pequeno porte. Não houve diferença estatisticamente significativa na riqueza de espécies dos ambientes sem turismo e com ecoturismo, sendo que a similaridade de espécies entre eles foi alta (88%. No entanto, três táxons apresentaram abundância inferior nos ambientes com turismo: Dasyprocta leporina (Linnaeus, 1766, Mazama spp. e Dasypus kappleri Krauss, 1862. Percebe-se, portanto, que o impacto negativo das atividades de ecoturismo desenvolvidas na área de estudo foi de pequena magnitude, em termos de riqueza e abundância de mamíferos de médio e grande porte. Assim

  17. Seed predation by mammals in forest fragments in Monteverde, Costa Rica

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    Federico A Chinchilla

    2009-09-01

    Full Text Available 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. Rev. Biol. Trop. 57 (3: 865-877. Epub 2009 September 30.Pocos estudios han evaluado la depredación de semillas en ambientes fragmentados, en éstos la menor diversidad de especies debe estar modificando las interacciones ecológicas. Se investigó la remoción de semillas por mamíferos en un bosque continuo y dos fragmentos en Monteverde

  18. 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.

  19. 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)

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    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...

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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

  7. 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

    2000-01-01

    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 ...

  8. 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.

  9. 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

  10. Área de actividad y movimientos de Liomys irroratus (Rodentia: Heteromyidae en una selva mediana de Tuxtepec, Oaxaca, México Activity area and movements of Liomys irroratus (Rodentia: Heteromyidae in semideciduos tropical forest of Tuxtepec, Oaxaca, Mexico

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    Antonio Santos-Moreno

    2012-06-01

    Full Text Available Se estimaron los movimientos y el área de actividad del ratón Liomys irroratus en una selva mediana del sureste del estado de Oaxaca, México. Los machos presentaron áreas de actividad más grandes que las hembras (126 m² vs. 21.1; asimismo, en la temporada seca las áreas fueron mayores que en la de lluvias, pero en este caso las diferencias no fueron estadísticamente significativas. El tamaño promedio anual de área de actividad para todos los individuos de la población se estimó en 87.48 m². Los machos no presentaron superposición de sus áreas de actividad con otros machos, y fue baja tanto entre hembras como entre individuos de sexos diferentes. Los machos tendieron a recorrer distancias promedio más grandes que las hembras (69.31 m vs. 33. En la temporada de lluvias los individuos se movieron significativamente más que en la seca (58.12 m vs. 44.19. El tamaño de las áreas de actividad de las hembras mostró una correlación estadísticamente significativa e inversa con el número de árboles y el de arbustos, y en estas áreas el número de oquedades y las pendientes son mayores que en las de los machos. Los resultados permiten suponer que la especie tiene un sistema de apareamiento de poligamia, manteniendo su territorio hasta que inicia la temporada reproductiva.We estimated the movements and activity area of the spiny pocket-mice Liomys irroratus in a semideciduos tropical forest at the southeastern of the state of Oaxaca, Mexico. Males have larger activity areas than females (126 m² vs. 21.1, also, in the rainy season these were higher than in the dry season, but in this case the differences were not statistically significant. The annual average size of the activity area for all individuals in the population was of 87.48 m². Males showed no overlap in their activity areas with other males, while between females and between members of different sexes this was low. Males showed average travel distances larger than females (69.31 m vs. 33. In the rainy season individuals moved significantly more than in the dry season (58.12 m vs. 44.19. The size of activity areas of the females showed a significant and inverse correlation with the number of trees and shrubs, and these areas had higher number of cavities and greater slope that those occupied by males. The results suggest that the species has a polygamous breeding system, where the territory is held until the beginning of the breeding season.

  11. 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

  12. 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...

  13. 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.

  14. 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.

  15. 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

  16. Las especies del género Gyropus Nitzsch, 1818 (Phthiraptera: Gyropidae parásitas de Octodontidae (Mammalia: Rodentia The species of the genus Gyropus Nitzch, 1818 (Phthiraptera: Gyropidae parasitic on the Octodontidae (Mammalia: Rodentia

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    DOLORES DEL CARMEN CASTRO

    2002-06-01

    Full Text Available Este trabajo tiene por finalidad otorgar status específico pleno a la subespecie Gyropus parvus elongatus Castro, Cicchino & Torres-Mura, 1987, describir la nueva especie Gyropus distinctus a partir de materiales recolectados sobre Octodon degus (Molina, 1782 y Octodon lunatus Osgood, 1943 procedentes del centro de Chile y, finalmente, ofrecer un análisis de las posibles razones de la distribución geográfica y del rango de hospedadores conocidos para estas tres especiesThe purpose of this paper is to give full specific status to the subspecies Gyropus parvus elongatus Castro, Cicchino & Torres-Mura, 1987, to describe the new species Gyropus distinctus collected in Octodon degus and O. lunatus from central Chile, along with an analysis of the possible causes than could explain their geographic and host range distributions known to date for these three species

  17. 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.

  18. 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.

  19. 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.

  20. The colonic groove or furrow: a comparative morphological study of six species of African mole-rats (Rodentia, Bathyergidae).

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    Kotzé, S H; van der Merwe, E L; Ndou, R; O'Riain, M J; Bennett, N C

    2009-08-01

    Herbivorous mammals such as nutrias, guinea pigs, chinchillas, and mole-rats have a longitudinal mucosal colonic groove (furrow) in their ascending colon, which is thought to play a role in the colonic separation mechanism (CSM). It is not known whether this groove is structurally modified to adapt to this function in mole-rat species. The morphology of this groove was studied in 32 mol-rats, four species, one of which consisted of three subspecies, endemic to southern Africa and two species found in eastern Africa. The macroscopic morphology of the groove was documented, and samples for histological examination were taken. The groove was wide at its origin at the cecocolic junction and was lined on either side by a row of papillae with the opposing papillae slightly offset in arrangement. The papillated groove gradually decreased in size toward the distal part of the ascending colon where it disappeared. This pattern was similar in all species except in Heterocephalus glaber, where the papillae were absent and the groove was lined by two longitudinal ridges. A histological examination of cross sections revealed that the mucosa covering the inner and outer walls of the groove was rich in mucous-secreting goblet cells. The walls of the groove contained smooth muscle extending from the inner circular smooth muscle layer at the base to the tips of the papillae in all species examined as well as arteries, lymphatic vessels, and prominent sinusoid-like veins. The groove could be demonstrated both macroscopically and histologically in three Bathyergus suillus fetuses of varying sizes. The sinusoid-like veins present in all grooves, regardless of macroscopic shape, suggest that they have a role in the functioning of the groove. (c) 2009 Wiley-Liss, Inc.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  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. 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).

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

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    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.

  11. 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.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.

  12. 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

  13. 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. PMID:23185576

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

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    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.

  15. 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.

  16. 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.

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

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    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.

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

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    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.

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

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    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.

  20. Estructura genética de un grupo de capibaras, Hydrochoerus hydrochaeris (Rodentia: Hydrocheridae en los Llanos orientales colombianos

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    Adriana Maldonado-Chaparro

    2011-12-01

    Full Text Available Los capibaras son los roedores más grandes del mundo, sin embargo, no se han realizado estudios genético poblacionales exhaustivos con ellos. En el presente trabajo se analizó la estructura genética de una manada de 31 capibaras (Hydrochoerus hydrochaeris muestreada en Hato Corozal, Departamento de Casanare en los Llanos Orientales de Colombia, mediante cinco marcadores microsatelitales. La diversidad genética se determinó en 0.61 y un número promedio de alelos de 5.2, lo cual se puede considerar medio-bajo para este tipo de marcadores. De los cinco marcadores empleados, tres mostraron proporciones genotípicas en concordancia con lo esperado en equilibrio Hardy-Weinberg, mientras que un marcador mostró un exceso significativo de homocigotos y otro un exceso significativo de heterocigotos. No se encontraron diferencias significativas para esos cinco marcadores entre machos y hembras de la manada muestreada. La aplicación de diferentes procedimientos para detectar posibles cambios demográficos históricos (expansiones poblacionales o cuellos de botella mostró claramente que la población analizada ha pasado por un cuello de botella extremadamente fuerte en épocas recientes. La limitada variabilidad genética encontrada y la fuerte evidencia de que la manada estudiada ha pasado por un cuello de botella reciente es probablemente el resultado de la cacería ilegal.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  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. 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.

  9. [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.

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

    Science.gov (United States)

    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.

  11. 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.

  12. Convergent evolution of aquatic foraging in a new genus and species (Rodentia: Muridae) from Sulawesi Island, Indonesia.

    Science.gov (United States)

    Rowe, Kevin C; Achmadi, Anang S; Esselstyn, Jacob A

    2014-06-17

    The island of Sulawesi, in Indonesia, lies at the crossroads of the Indo-Australian Archipelago and has remained isolated from the Asian (Sunda) and Australian (Sahul) continental shelves for at least the last 10 million years. Of the 50 native species of rodents on Sulawesi, all are endemic and represent the evolution of a variety of ecological and morphological forms within the Muridae and Sciuridae. Carnivorous rodents have evolved, perhaps independently, in Muridae from the Philippines, Sulawesi, and Sahul, but semi-aquatic murids are only known from Sahul. Here we describe a new genus and species of insectivorous water rat from Sulawesi. Phylogenetic analyses demonstrate that it is related to the shrew rats of Sulawesi and represents an origin of aquatic carnivory that is independent from the evolution of water rats on Sahul. Many areas of Sulawesi have not been surveyed systematically and current lists of mammal species are likely to dramatically underestimate actual diversity.

  13. Caracterização morfológica dos dentes de mocó Kerodon rupestris: Mammalia: Rodentia

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    Juliana Montovani Thomaz

    2006-10-01

    Full Text Available O Kerodon rupestris, também conhecido como mocó, é um roedor herbívoro encontrado no Brasil. A dentição dos mamíferos apresenta-se variável de acordo com as espécies embora seja formada pelos mesmos componentes: esmalte, dentina, cemento e polpa. Neste estudo foram utilizadas sete cabeças de Kerodon rupestris, adultos, de ambos os sexos. Na cavidade oral do Kerodon rupestris, devido ao tamanho relativamente grande dos incisivos, estes se destacaram dos demais e foram encontrados um par em cada mandíbula. Dois pares de pré-molares e três pares de molares foram encontrados, sendo representados na fórmula 2x (I 1/1, C 0/0, P 1/1, M 3/3. Os molares apresentaram duas cúspides, conformação que conferia a estes dentes um aspecto serrilhado. Microscopicamente os dentes incisivos, pré-molares e molares foram classificados como hipsodontes, ou seja, dentes em constante erupção.

  14. 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.

  15. Sexual size dimorphism in ground squirrels (Rodentia: Sciuridae: Marmotini) does not correlate with body size and sociality

    OpenAIRE

    Matějů, Jan; Kratochvíl, Lukáš

    2013-01-01

    Introduction Sexual size dimorphism (SSD) is a widespread phenomenon in animals including mammals. It has been demonstrated that across species, the direction and magnitude of sexual dimorphism in body size often corresponds to social systems. Moreover, many animal lineages conform to “Rensch’s rule”, which states that male-biased SSD increases with body size. We tested whether considerable differences in sociality and large variation in body size were connected with the evolution of SSD in t...

  16. Sexual size dimorphism in ground squirrels (Rodentia: Sciuridae: Marmotini) does not correlate with body size and sociality.

    Science.gov (United States)

    Matějů, Jan; Kratochvíl, Lukáš

    2013-05-14

    Sexual size dimorphism (SSD) is a widespread phenomenon in animals including mammals. It has been demonstrated that across species, the direction and magnitude of sexual dimorphism in body size often corresponds to social systems. Moreover, many animal lineages conform to "Rensch's rule", which states that male-biased SSD increases with body size. We tested whether considerable differences in sociality and large variation in body size were connected with the evolution of SSD in the structural body size of ground squirrels, an otherwise ecologically relatively homogenous group of terrestrial rodents. We found the general trend of male-biased SSD in ground squirrels, however, male size increases nearly perfectly isometrically with female size among species and sociality does not explain departures from this relationship. Species with different sociality grades significantly differ in body size, with the most social species tending to be the largest. We suggest that lack of conformity with Rensch´s rule in ground squirrels may be attributed to their low variation in SSD, and briefly discuss three potential causes of small magnitude of SSD in the structural size in rodents: low selection on SSD in structural dimensions, ontogenetic and genetic constraints and the existence of ecological/selection factors preventing the evolution of extensive SSD.

  17. 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.

  18. 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.

  19. 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.

  20. 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...

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

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    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.

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

    Science.gov (United States)

    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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

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

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    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.

  11. 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.

  12. Corrections in the taxonomic position in the helminth-fauna of Apodemus spp. (Rodentia in the Czech Republic

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    František Tenora

    2004-01-01

    Full Text Available Since 1955 as yet in the territory of the Czech Republic in 4 species of the genus Apodemus (namely A. flavicollis, A. sylvaticus, A. microps and A. agrarius, 49 species of parasitic worms were registered in total. At their revision, comparing with the modern literature from the last five decades, the author has approached to several corrections. Subjects are, first of all, several opinions on the species from the genera Plagiorchis, Echinostoma, Aprostatandrya, Catenotaenia, Hymenolepis, Syphacia, Heligmosomum, Heligmosomoides, Ganguleterakis and Aonchotheca. Of highly characteristic helminths parasitizing Apodemus spp. in Czech Republic, they are from the class Trematoda: Brachylaemus recurvus; from the class Cestoda: Paranoplocephala omphalodes, Skrjabinotaenia lobata, Catenotaenia sp., Hymenolepis straminea; from the class Nematoda: Syphacia stroma, S. frederici, S. agraria, Heligmosomum pseudocostellatum, Heligmosomoides polygyrus, Aonchotheca murissylvatici, Calodium hepaticum, Trichocephalus muris; from the class Acanthocephala: Moniliformis moniliformis. A number of species has to be verified, in a future, by methods of molecular biology.

  13. 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.

  14. 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.

  15. 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.

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

    Science.gov (United States)

    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.

  17. 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

    there was a continuity between both rainfall peaks. Analyses of size and shape following both Huxley-Jolicoeur and Gould-Mosimann approaches revealed that the three groups differ significantly both in size and shape. In both cases, the importance of the environment in assessing growth trajectories during post...

  18. 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.

  19. 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...

  20. 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.

  1. Characterisation of the vascular pathology in Sigmodon hispidus (Rodentia: Cricetidae following experimental infection with Angiostrongylus costaricensis (Nematoda: Metastrongylidae

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    Danielle Ingrid Bezerra de Vasconcelos

    Full Text Available BACKGROUND Angiostrongylus costaricensis is a nematode that causes human abdominal angiostrongyliasis, a disease found mainly in Latin American countries and particularly in Brazil and Costa Rica. Its life cycle involves exploitation of both invertebrate and vertebrate hosts. Its natural reservoir is a vertebrate host, the cotton rat Sigmodon hispidus. The adult worms live in the ileo-colic branches of the upper mesenteric artery of S. hispidus, causing periarteritis. However, there is a lack of data on the development of vasculitis in the course of infection. OBJECTIVE To describe the histopathology of vascular lesions in S. hispidus following infection with A. costaricensis. METHODS Twenty-one S. hispidus were euthanised at 30, 50, 90 and 114 days post-infection (dpi, and guts and mesentery (including the cecal artery were collected. Tissues were fixed in Carson’s Millonig formalin, histologically processed for paraffin embedding, sectioned with a rotary microtome, and stained with hematoxylin-eosin, resorcin-fuchsin, Perls, Sirius Red (pH = 10.2, Congo Red, and Azan trichrome for brightfield microscopy analysis. FINDINGS At 30 and 50 dpi, live eggs and larvae were present inside the vasa vasorum of the cecal artery, leading to eosinophil infiltrates throughout the vessel adventitia and promoting centripetal vasculitis with disruption of the elastic layers. Disease severity increased at 90 and 114 dpi, when many worms had died and the intensity of the vascular lesions was greatest, with intimal alterations, thrombus formation, iron accumulation, and atherosclerosis. CONCLUSION In addition to abdominal angiostrongyliasis, our data suggest that this model could be very useful for autoimune vasculitis and atherosclerosis studies.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    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].

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

    Science.gov (United States)

    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.

  5. Dieta del capibara Hydrochaeris hydrochaeris (Rodentia: Hydrochaeridae en Caño Limón, Arauca, Colombia

    Directory of Open Access Journals (Sweden)

    Jimena Forero-Montaña

    2003-06-01

    Full Text Available Estudiamos la composición y variación estacional de la dieta del chigüiro (Hydrochaeris hydrochaeris en los esteros de Caño Limón, por medio de observaciones directas del consumo de las plantas. Los chigüiros se alimentaron exclusivamente de plantas y su dieta estuvo compuesta por 89 especies, pertenecientes a 22 familias. El 63 % de las especies son nuevos registros para la dieta del chigüiro. Las cuatro familias mas consumidas fueron Poaceae, Cyperaceae, Leguminosae y Pontederiaceae, las cuales representaron el 94% del total de la dieta. Solo siete especies representaron el 60% del total de la dieta, así: los pastos Hymenachne amplexicaulis (16.9%, Digitaria bicornis (10.9%, Paspalum fasciculatum (10.9%, Cynodon dactylon (6.8%, Urochloa arrecta (4.5% y Panicum maximum (4.4% y la ciperácea Rynchospora corymbosa (4.4%. Se presentó variación en la composición de la dieta de los chigüiros durante las épocas de muestreo.We studied the composition and seasonal variation of the diet of the capybara (Hydrochaeris hydrochaeris in the flooded savannas of Caño Lim��n, 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. [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.

  12. 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.

  13. 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.

  14. 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.

  15. 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...

  16. 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.

  17. [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.

  18. 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...

  19. 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...

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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

  7. 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...

  8. An update on the distribution and nomenclature of fleas (Order Siphonaptera) of bats (Order Chiroptera) and rodents (Order Rodentia) from La Rioja Province, Argentina

    Science.gov (United States)

    Berrizbeitia, M. Fernanda López; Sánchez, R. Tatiana; Barquez, Ruben M.; Díaz, M. Monica

    2017-01-01

    Abstract The mammalian and flea fauna of La Rioja Province is one of the least known from northwestern Argentina. In this study, the distribution and nomenclature of 13 species of fleas of bats and rodents from La Rioja Province are updated. Four species of fleas are recorded for the first time in La Rioja Province including a new record for northwestern Argentina, and two new flea-host associations. An identification key and distribution map are included for all known species of Siphonaptera of bats and rodents from La Rioja Province, Argentina. PMID:28769701

  9. 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...

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. Helmintos parásitos de la rata Sigmodon hispidus (Rodentia: Cricetidae de un hábitat estacional y otro perenne en Costa Rica

    Directory of Open Access Journals (Sweden)

    Beatriz Rodríguez

    2000-03-01

    Full Text Available La fauna helmintológica de ejemplares de Sigmodon hispidus capturados en Costa Rica, varió de acuerdo a la región de procedencia. En las ratas provenientes de una zona extensa del Pacífico seco, (Guanacaste que ofrecía una dieta variada, se encontraron 6 especies de nemátodos y 2 especies de céstodos. En las provenientes de la Meseta Central, (Alajuela que disfrutaban de una dieta única y abundante, se aislaron solamente dos especies: una de ellas, Angiostrongylus costaricensis, de gran importancia en salud humana, estuvo presente en el 42% de las ratas de esa región.The helminthological fauna of the cotton rat, Sigmodon hispidus in a tropical environment varies according to habitat and feeding behavior. Six species of nematodes (Longistriata adunca, Trichostrongylus sigmodontis, Strongyloides sigmodontis, Litomosoides carinii, Monodontus sp. and Protospirura sp. and two species of cestodes (Hymenolepis diminuta and Raillietina sp. were found in rats from extensive dry lands in Guanacaste where hot temperatures and heterogeneous diet are the rule. Only two species of nematodes (Longistriata adunca and Angiostrongylus costaricensis were found in rats collected in a humid pineapple plantation in the Central Plateau (Alajuela where mild temperatures predominate. A. costaricensis, a metastrongylid of medical importance, was found in 42% of them.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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.

  2. 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...

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818 em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae

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    Omar dos Santos Carvalho

    1976-10-01

    Full Text Available Junto ao Lago da Pampulha, Belo Horizonte, MG, foram capturados (julho/72-novembro/73 28 exemplares de Holochilus brasiliensis, dos quais 11 (39,3% eliminavam nas fezes ovos viáveis de S. mansoni. Miracídios da cepa mencionada ("H" infectaram Biomphalaria glabrata e as cercárias obtidas também infectaram camundongos albinos, recuperando-se, ao final do experimento, 35,3% de vermes adultos. Por outro lado, cercárias de cepa humana ("LE" de S. mansoni infectaram sete exemplares de H. brasiliensis, nascidos em laboratório, recuperando-se no fim de 60 dias, 30,5% de vermes adultos. Estudos anatomapatológicos de H. brasiliensis demonstraram infecção generalizada, encontrando-se granuloma no esôfago, estômago, intestino (delgado e grosso, fígado, baço, pâncreas e linfonodos abdominais. Espessamentos fibrosos da íntima da veia porta, granulomas em espaços porta e fibrose incipiente dos espaços porta e interlobular foram lesões decorrentes da presença de ovos de S. mansoni encontrados no fígado. Em ambiente semi-natural, foi possível fechar o ciclo do S. mansoni sem direta participação humana, utilizando-se B. glabrata experimentalmente infectadas com trematódeos da cepa "LE", H. brasiliensis nascidos em laboratório e B. glabrata nascida no ambiente semi-natural estabelecido. Verificou-se que ambas as cepas ("H" e "LE" comportaram-se de maneira análoga, não sendo verificadas, também, diferenças morfológicas entre os ovos e vermes adultos de ambas. As observações, realizadas no campo e no laboratório demonstraram que o Holochilus brasiliensis é bom hospedeiro de Schistosoma mansoni. Assim, em determinadas áreas e sob certas condições ecológicas, o cricetídeo em questão poderá, efetivamente, integrar-se ao ciclo do trematódeo na natureza, independente ou paralelamente à presença do homem. Assinala-se, finalmente, que o presente trabalho relata o segundo fechamento do ciclo biológico de S. mansoni em condições ditas semi-naturais. Os primeiros estudos, entretanto, de Antunes, Milward de Andrade, Katz & Coelho4,,em 1971 e de Antunes5, em 1971 foram feitos utilizando-se o Nectomys s. squamipes.Close to the Pampulha Lake, Belo Horizonte, MG (Brazil, there were collected (july/72 -November/73 28 specimens of Holochilus brasiliensis, 11 of them (39.3% eliminating S. mansoni viable eggs in their faeces. Miracidia from the strain above ("H" could infected Biomphalaria glabrata, the cercariae shed later being also able to infect albino mice, from whose faeces 35,3% of adult worms were recovered in the end of the experiment. S. mansoni cercariae from human strain ("LE" infected 7 H. brasiliensis laboratory specimens, and 30,5% of adult worms could be recovered in the end of 60 days. Anatomopathological studies of H. brasiliensis demonstrated generalized infection, granulomes being detected in the esophagus, stomach, intestines (small and large, tiver, spleen, pancreas and abdominal lymphnodes. Fibrous thickenning of the portal vein intima, granulomes in portal spaces an incipient fibrosis of portal and interlobular spaces were the lesion triggered by the presence of S. mansoni eggs in the liver. In semi-natural surroundings (Fig. 1, the life cycle of S. mansoni could be completed, with no human interference, by using B. glabrata experimentally infected with trematodes from "LE" strain, laboratory-bred H. brasiliensis and B. glabrata specimens from hat seminatural surroundings. It was observed that both strains ("H" and "LE" displayed similar behaviour, no morphological differences having been detected between their eggs and adult worms. Field and laboratory studies demonstrated Holochilus brasiliensis to be a satisfactory intermediate host of S. mansoni. It is than possible that, under certains ecological conditions, the cricetids under study may eventually be integrated in the trematode natural cycle, independently from or parallely the presence of man. It must finally be pointed out that the present paper reports the second case of lifecycle completion under semi-natural conditions. The former studies4,5, however, were conducted on Nectomys s. squamipes.

  8. 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.

  9. 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...

  10. 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....

  11. 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.

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

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    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.

  13. 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, ...

  14. Systematics and evolution of the Meriones shawii/grandis complex (Rodentia, Gerbillinae) during the Late Quaternary in northwestern Africa: Exploring the role of environmental and anthropogenic changes

    Science.gov (United States)

    Stoetzel, Emmanuelle; Cornette, Raphaël; Lalis, Aude; Nicolas, Violaine; Cucchi, Thomas; Denys, Christiane

    2017-05-01

    Rodents of the Meriones shawii/grandis complex have been attested to in North Africa since the Middle Pleistocene and are abundant in archaeological sites. Today, they are widely spread and represent a major pest to local human populations. This complex, therefore, represents an accurate model for investigating the roles of climate change and human impact in shaping Quaternary faunal diversity and distribution. Many gray areas still exist regarding the systematics, ecology and geographical distribution of this complex, for both present and past populations. The purpose of this study is to compare modern genotyped and fossil Meriones specimens in order to 1) clarify the current systematics and distribution of the Meriones populations of the shawii/grandis complex, 2) document the taxonomic diversity in fossil Meriones from northwestern Africa, and 3) track their phenotypic and biogeographic evolution through time. To answer these questions we used geometric morphometrics on skulls (landmarks) and first upper molars (landmarks and sliding landmarks). We evidenced the existence of two morpho-groups within the M. shawii/grandis complex, with a clear geographic pattern (M. grandis in Morocco vs. M. shawii in Algeria and Tunisia). Currently only one morpho-group, attributed to M. grandis, seems to exist in Morocco, with a small overlap with M. shawii in the most eastern part of the country. However, according to fossil data, M. shawii was also present in Atlantic Morocco during the Late Pleistocene. We have also highlighted the impact of Holocene climate change and habitat anthropization on this arid adapted group. During the Middle Holocene, a major climatic event (last interglacial optimum) seems to have induced a demographic collapse in Moroccan populations and the disappearance of the shawii clade from Morocco (except in the most eastern areas). Both species then re-expanded, benefitting from the increasing aridity and the new ecological niche driven by agriculture dispersal from the Neolithic onwards.

  15. 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....

  16. 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.

  17. UN ÍNDICE PARA LA EVALUACIÓN DEL HÁBITAT DE AGOUTI TACZANOWSK/1 (RODENTIA: AGOUTIDAE EN ÁREAS DE BOSQUE ANDINO NUBLADO

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    Jairo Pérez-Torres

    2002-06-01

    Full Text Available Se presenta un índice que permitirá evaluar el hábitat de la "Lapa andiim" o "Tinajo" (Agouti taczanowskii en zonas de bosque andino nublado. El objetivo fundamental de este índice, es obtener elementos que sirvan para la toma de decisiones en cuanto al diseño de áreas de reserva y planes de manejo sobre esta especie. Este índice se basa en la aplicación de criterios tanto cualitativos como cuantitativos, los cuales son tabulados y computados para sacar un valor de calidad de hábitat para cada uno de los ambientes bajo estudio. Los valores del índice de diferentes áreas pueden ser comparados para determinar de manera jerárquica cuál es más adecuado para realizar actividades particulares de manejo o conservación de esta especie en zonas de bosque andino. El índice se basa en doce variables: porcentaje de uso del área, abundancia del "Tinajo", explotación humana, grado de protección, riqueza en la dieta, cobertura foliar de las especies vegetales, accesibilidad a las especies vegetales que hacen parte de la dieta, heterogeneidad del hábitat, disponibilidad de agua, áreas potenciales de reproducción, presencia de predadores y factores antrópicos.

  18. 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

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    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.

  19. 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.

  20. First detection of Leishmania killicki (Kinetoplastida, Trypanosomatidae) in Ctenodactylus gundi (Rodentia, Ctenodactylidae), a possible reservoir of human cutaneous leishmaniasis in Tunisia.

    Science.gov (United States)

    Jaouadi, Kaouther; Haouas, Najoua; Chaara, Dhekra; Gorcii, Mohamed; Chargui, Najla; Augot, Denis; Pratlong, Francine; Dedet, Jean-Pierre; Ettlijani, Selim; Mezhoud, Habib; Babba, Hamouda

    2011-08-11

    Leishmania killicki was originally described in 1980 in southeast Tunisia. It was also recently reported in Lybia and Algeria. Nevertheless, neither vector nor reservoirs of this parasite are known. The identification of the vector and the animal reservoir host of L. killicki is critical for the establishment of an efficient control strategy. blood, popliteal lymph node, spleen, bone marrow, liver and skin were collected from 50 rodents in 2009 in south western Tunisia. Samples were smeared onto glass slides, cultured on NNN medium and tested by polymerase chain reaction for Leishmania detection. Parasites were detected by PCR from 10 Psammomys obesus and from two Ctenodactylus gundi. Parasite identification was performed simultaneously by internal transcribed spacer 1 PCR-RFLP and by PCR sequencing. Both Leishmania major and Leishmania killicki were identified from infected Psammomys and Ctenodactylus gundi respectively. This is the first report of Leishmania killicki identified from Ctenodactylus gundi in Tunisia. This result supports the assumption that C. gundi is a potential reservoir for Leishmania killicki.

  1. First detection of Leishmania killicki (Kinetoplastida, Trypanosomatidae in Ctenodactylus gundi (Rodentia, Ctenodactylidae, a possible reservoir of human cutaneous leishmaniasis in Tunisia

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    Ettlijani Selim

    2011-08-01

    Full Text Available Abstract Background Leishmania killicki was originally described in 1980 in southeast Tunisia. It was also recently reported in Lybia and Algeria. Nevertheless, neither vector nor reservoirs of this parasite are known. The identification of the vector and the animal reservoir host of L. killicki is critical for the establishment of an efficient control strategy. Findings blood, popliteal lymph node, spleen, bone marrow, liver and skin were collected from 50 rodents in 2009 in south western Tunisia. Samples were smeared onto glass slides, cultured on NNN medium and tested by polymerase chain reaction for Leishmania detection. Parasites were detected by PCR from 10 Psammomys obesus and from two Ctenodactylus gundi. Parasite identification was performed simultaneously by internal transcribed spacer 1 PCR-RFLP and by PCR sequencing. Both Leishmania major and Leishmania killicki were identified from infected Psammomys and Ctenodactylus gundi respectively. Conclusion This is the first report of Leishmania killicki identified from Ctenodactylus gundi in Tunisia. This result supports the assumption that C. gundi is a potential reservoir for Leishmania killicki.

  2. 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...

  3. Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818 em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae

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    Omar dos Santos Carvalho

    1976-10-01

    Full Text Available Junto ao Lago da Pampulha, Belo Horizonte, MG, foram capturados (julho/72-novembro/73 28 exemplares de Holochilus brasiliensis, dos quais 11 (39,3% eliminavam nas fezes ovos viáveis de S. mansoni. Miracídios da cepa mencionada ("H" infectaram Biomphalaria glabrata e as cercárias obtidas também infectaram camundongos albinos, recuperando-se, ao final do experimento, 35,3% de vermes adultos. Por outro lado, cercárias de cepa humana ("LE" de S. mansoni infectaram sete exemplares de H. brasiliensis, nascidos em laboratório, recuperando-se no fim de 60 dias, 30,5% de vermes adultos. Estudos anatomapatológicos de H. brasiliensis demonstraram infecção generalizada, encontrando-se granuloma no esôfago, estômago, intestino (delgado e grosso, fígado, baço, pâncreas e linfonodos abdominais. Espessamentos fibrosos da íntima da veia porta, granulomas em espaços porta e fibrose incipiente dos espaços porta e interlobular foram lesões decorrentes da presença de ovos de S. mansoni encontrados no fígado. Em ambiente semi-natural, foi possível fechar o ciclo do S. mansoni sem direta participação humana, utilizando-se B. glabrata experimentalmente infectadas com trematódeos da cepa "LE", H. brasiliensis nascidos em laboratório e B. glabrata nascida no ambiente semi-natural estabelecido. Verificou-se que ambas as cepas ("H" e "LE" comportaram-se de maneira análoga, não sendo verificadas, também, diferenças morfológicas entre os ovos e vermes adultos de ambas. As observações, realizadas no campo e no laboratório demonstraram que o Holochilus brasiliensis é bom hospedeiro de Schistosoma mansoni. Assim, em determinadas áreas e sob certas condições ecológicas, o cricetídeo em questão poderá, efetivamente, integrar-se ao ciclo do trematódeo na natureza, independente ou paralelamente à presença do homem. Assinala-se, finalmente, que o presente trabalho relata o segundo fechamento do ciclo biológico de S. mansoni em condições ditas semi-naturais. Os primeiros estudos, entretanto, de Antunes, Milward de Andrade, Katz & Coelho4,,em 1971 e de Antunes5, em 1971 foram feitos utilizando-se o Nectomys s. squamipes.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  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. 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).

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

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    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.

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

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    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.

  13. 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...

  14. 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

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    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

  15. 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

  16. Penial morphology in three species of Brazilian Tuco-tucos, Ctenomys torquatus, C. minutus, and C. flamarioni (Rodentia: Ctenomyidae Morfologia peniana de três espécies de tuco-tuco do Brasil - Ctenomys torquatus, C. minutus e C. flamarioni (Rodentia: Ctenomyidae

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    O. Rocha-Barbosa

    2013-02-01

    Full Text Available 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.O presente estudo analisa a morfologia do glans penis e do baculum de três tuco-tucos do Brazil - Ctenomys torquatus Lichtenstein, 1830, Ctenomys minutus Nehring, 1887, e Ctenomys flamarioni Travi, 1981 - com a finalidade de identificar possíveis variações e elucidar mais sobre grupo taxonômico complexo. Foram usados pênis fixados de 15 indivíduos adultos das espécies listadas anteriormente. Para uma análise mais detalhada do baculum, o pênis foi submetido a dissecções e diafanização, enquanto que, para a análise da superfície do glans penis, foi usada a técnica de microscopia eletrônica de varredura (MEV. Os resultados exibiram significativas diferenças na morfologia do baculum entre as três espécies. Enquanto C. minutus apresenta um baculum com uma ponta em forma de V característica, o baculum de C. flamarioni é fino ao longo do osso, com as pontas proximal e distal arredondadas. Ctenomys torquatus apresenta um baculum mais curto e largo, similar ao descrito anteriormente para a espécie. Análises da microestrutura na superfície do glans penis revelaram diferenças interespecíficas, com os espinhos penianos variando em forma, tamanho e, especialmente, densidade. Apesar de C. torquatus ter um pênis relativamente pequeno, apresenta a maior densidade de espinhos penianos, o que sugere uma complexa ornamentação peniana nesta espécie.

  17. 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

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    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.

  18. 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.

  19. 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

  20. Aspectos ecológicos del roedor arborícola Rhipidomys Latimanus Tomes, 1860, (Rodentia: Cricetidae en el oriente de Cundinamarca, Colombia Aspectos ecológicos del roedor arborícola Rhipidomys Latimanus Tomes, 1860, (Rodentia: Cricetidae en el oriente de Cundinamarca, Colombia

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    Montenegro Díaz Olga

    1991-12-01

    Full Text Available The population biology of Rhipidomys latimanus was studied by capture-recapture methods from February to August, 1989, on a grid of 1.2 ha of high Andean forest and paramo vegetation, at 3000 m.sl, elevation in the eastern part of departament of Cundinamarca, Colombia. Survivor ship was moderately high through the study period, and highest population density was associated with periods of maximum precipitation. Reproduction activity appeared to be constant throughout the study period. Average home range was stimated to  be 0.21 ha. Information on diets is given and the possible role of Rhipidomys latimanus in seed dispersal is discussed. Se estudiaron aspectos demográficos de Rhipidomys latimanus de febrero a agosto de 1989, utilizando la técnica de captura-recaptura en una cuadrícula de 1.2 Ha. con vegetación de Bosque altoandino y páramo a una altura superior a los 3.000 msnm en el oriente de Cundinamarca, Colombia. La densidad poblacional se incrementó en los meses de mayor precipitación y la supervivencia se mantuvo entre moderada y alta. La actividad reproductiva fue constante en esta época del año, El área de acción promedio de la especie se estimó en 0.21 hectáreas. Se presenta información sobre la dieta de este roedor y su posible papel como dispersor de semillas.

  1. 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

  2. Seed predation and defleshing in the agouti-dispersed palm Astrocaryum standleyanum

    NARCIS (Netherlands)

    Jansen, Patrick A.; Elschot, Kelly; Verkerk, P. Johannes; Wright, S. Joseph

    The agouti (Dasyprocta punctata) meticulously defleshes Astrocaryum standleyanum palm seeds before scatter hoarding. On Barro Colorado Island, Panama, we experimentally tested three hypotheses on how this behaviour could reduce seed predation to the mutual benefit of the tree and the rodent. The

  3. Seed predation and defleshing in the agouti-dispersed palm Astrocaryum standleyanum

    NARCIS (Netherlands)

    Jansen, P.A.; Elschot, K.; Verkerk, P.J.; Wright, S.J.

    2010-01-01

    The agouti (Dasyprocta punctata) meticulously defleshes Astrocaryum standleyanum palm seeds before scatter hoarding. On Barro Colorado Island, Panama, we experimentally tested three hypotheses on how this behaviour could reduce seed predation to the mutual benefit of the tree and the rodent. The fir

  4. 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.

  5. 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.

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    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.

  6. 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.

  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. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. [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.

  14. Mazzanema n. gen. and Mazzanema fortuita n. comb. for Longistriata fortuita Freitas, Lent, and Almeida, 1937 (Nematoda: Heligmonellidae), a parasite of the marsh rat Holochilus chacarius (Rodentia: Cricetidae) from northern Argentina.

    Science.gov (United States)

    Digiani, María Celina; Notarnicola, Juliana; Paulos, María Soledad

    2013-10-01

    The species described as Longistriata fortuita Freitas, Lent, and Almeida, 1937 is here redescribed from new material collected from the type host, Holochilus chacarius balnearum Thomas, and the type locality, San Martín del Tabacal, Salta, Argentina. Neotypes are designed for the species since the type material deposited by the authors is lost. The original description did not include the synlophe or the female and both are here described. Several characters of the synlophe as the number of ridges (14-19), the ridges continuous and all around body, and the presence of a gradient of size of the ridges allow us to place the species within the Heligmonellidae, Nippostrongylinae. The species possesses a unique combination of characters as the synlophe having a carene together with characters of the caudal bursa as the pattern 1-3-1 and the strong development of the dorsal lobe and ray, which precludes its inclusion in any known genus of Nippostrongylinae. A new genus Mazzanema n. gen. is proposed for it, resulting in the new combination Mazzzanema fortuita n. comb.

  15. 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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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...

  17. 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.

  18. 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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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...

  20. 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.

  1. [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 ...

  2. 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.

  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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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.

  7. 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.

  8. 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

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    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.

  9. Seed predation and defleshing in the agouti-dispersed palm Astrocaryum standleyanum

    OpenAIRE

    Jansen, P.A.; Elschot, K.; Verkerk, P. J.; Wright, S. J.

    2010-01-01

    The agouti (Dasyprocta punctata) meticulously defleshes Astrocaryum standleyanum palm seeds before scatter hoarding. On Barro Colorado Island, Panama, we experimentally tested three hypotheses on how this behaviour could reduce seed predation to the mutual benefit of the tree and the rodent. The first and established hypothesis – that defleshing reduces seed predation by bruchid beetles by intercepting larvae – was rejected. Experiments in which manually defleshed seeds or entire fruits were ...

  10. The importance of pollen chemistry in evolutionary host shifts of bees

    Science.gov (United States)

    Vanderplanck, Maryse; Vereecken, Nicolas J.; Grumiau, Laurent; Esposito, Fabiana; Lognay, Georges; Wattiez, Ruddy; Michez, Denis

    2017-01-01

    Although bee-plant associations are generally maintained through speciation processes, host shifts have occurred during evolution. Understanding shifts between both phylogenetically and morphologically unrelated plants (i.e., host-saltation) is especially important since they could have been key processes in the origin and radiation of bees. Probably far from being a random process, such host-saltation might be driven by hidden constraints associated with plant traits. We selected two clades of oligolectic bees (i.e., Colletes succinctus group and Melitta leporina group) foraging on co-flowering but unrelated host-plants to test this hypothesis. We analyzed floral scent, floral color and chemical composition of pollen from host and non-host plants of these two clades. We did not find evidence for host-plant evolution in the Melitta leporina group driven by one of the assayed floral traits. On the contrary, hosts of the C. succinctus group display similar primary nutritive content of pollen (i.e., amino acids and sterols) but not similar floral scent or color, suggesting that shared pollen chemistry probably mediates saltation in this clade. Our study revealed that constraints shaping floral associations are diverse and clearly depend on species life-history traits, but evidence suggests that pollen chemistry may act as a major floral filter and guide evolutionary host-shifts. PMID:28216663

  11. 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.

  12. 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....

  13. Reproductive Characteristics of Rodent Assemblages in Cultivated Regions of Central Argentina

    Science.gov (United States)

    1992-01-01

    Secretaria de Estado Ecologia de Caloin ’vs laucha (Rodentia. Cricetidae) de Salud Puiblica, Buenos Aires. Argentina. 45 pp. en el dcpartamento de Rio...340-344. ZULETA, G. A. 1989. Estrategias de historia de vida HoDARA, V. L., A. E. KAJON, C. QurNT~ANS. L. en el raton del pastizal pampeano. .4kodon

  14. 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.

  15. 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

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    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.

  16. New mammalian records in the Parque Nacional Cerros de Amotape, northwestern Peru

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    Cindy M. Hurtado

    2015-04-01

    Full Text Available The Pacific Tropical Rainforest and Equatorial Dry Forest are found only in southern Ecuador and northern Peru, and are among the most poorly known ecosystems of South America. Even though these forests are protected in Parque Nacional Cerros de Amotape (PNCA, they are threatened by fragmentation because of farming and agriculture. The aim of this study was to determine the medium and large mammalian species richness, using transect census, camera trapping, and specimen bone collection. Nine transects were established and 21 camera trap stations were placed along 16 km2 in three localities of PNCA, from August 2012 to April 2013. Total sampling effort was 215 km of transects and 4077 camera-days. We documented 22 species; including 17 with camera trapping, 11 with transect census, and 10 with specimen collection.  Camera traps were the most effective method, and four species (Dasyprocta punctata, Cuniculus paca, Leopardus wiedii and Puma concolor were documented only with this method. This comprised the first Peruvian record for Dasyprocta punctata, and the first record for the western slope of the Peruvian Andes for Cuniculus paca. Also, both specimen collections and sightings confirm the presence of Potos flavus, first record in the western slope of the Peruvian Andes. Panthera onca, Tremarctos ornatus and Saimiri sciureus are considered locally extinct, while several species are in need of further research. We highlight the importance of the high diversity of this rainforests and encourage local authorities to give the area the highest priority in conservation.

  17. 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

  18. 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...

  19. 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...

  20. 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...

  1. Rodent phylogeny revised: analysis of six nuclear genes from all major rodent clades

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    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.

  2. An Autochthonous Case of Echinococcus vogeli Rausch & Bernstein, 1972 Polycystic Echinococcosis in the State of Rondônia, Brazil

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    Rosângela Rodrigues-Silva

    2002-01-01

    Full Text Available The present case report refers to a patient from the State of Rondônia, North region of Brazil, attended with clinical suspicion of hepatic echinococcosis. Examination by imaging (ultrasonography and computerized tomography revealed a conglomerate of cystic lesions, with mobile contents within the cyst. The serology (immunoblot for Echinococcus sp. was positive (21 and 31 kDa bands. This case is the first reported in Rondônia, suggesting the need to investigate the polycystic echinococcosis in individuals with hepatic cysts from areas of tropical forest and hunting habits where wild life was present as wild dogs, cats and rodents, particularly Agouti paca (paca and Dasyprocta aguti (agouti.

  3. Notas sôbre a evolução do virus vacínico em animais silvestres da fauna brasileira

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    Cicero Alves Moreira

    1956-06-01

    Full Text Available A note on the evolution of cow-pox virus in wild animals of Brazilian fauna. We have tried the sensibility of wild animals of Brazilian fauna to the cow-pox virus. The following specimens were submitted to experiences: Procyon cancrivorus, Hydrochoerus capybara, Cavea aperea, Coendu villosus, Didelphis aurita, Bradypus tridactylus, Euphractus sexcintus, Tamandua tetradactylus, Nasua narica, Dasyprocta aguti and Testudo tabulata. In all these animals, - excepting Bradypus tridactylus - we have obtained an infection with incubation (five days, aspect and duration similar to cow-pox of the laboratorial animals (calf and rabbit. In the Bradypus tridactylus howewer, the incubation was very long. Only after 30 days of inoculation we verified the infection with the formation of vesiculae and postulae.

  4. Seed dispersal and spatial distribution of Attalea geraensis (Arecaceae) in two remnants of Cerrado in Southeastern Brazil

    Science.gov (United States)

    Bonjorne de Almeida, Lilian; Galetti, Mauro

    2007-09-01

    The seed dispersal system of Attalea geraensis (Arecaceae), an acaulescent palm, was investigated during one year in two Cerrado fragments in the state of São Paulo, southeastern Brazil. A. geraensis had inflorescences and infrutescences throughout the year. Two scatter-hoarding rodents (the spiny rat, Clyomys bishopi and agoutis, Dasyprocta azarae) were identified as seed predators/dispersers, able to move seeds up to 30 m from the palms, although most of the fruits (57.5%) were dispersed less than 2 m. The removal rates were high and after 20 days, 97.2% of the fruits were removed. Fruit fate was not related to fruit mass, length and diameter. The application of Morisita's index showed a more clumped distribution of adults in the smaller fragment, probably because of the absence of agoutis. Higher seed removal by rodents in the large Cerrado remnant may decrease seed predation by beetles.

  5. Arborescent palm seed morphology and seedling distribution

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    Rodolfo Salm

    Full Text Available This study examines how the seed morphology of two large arborescent palms, Attalea maripa (Aubl. Mart. and Astrocaryum aculeatum G. Mey, may affect their seed shadow in a seasonally dry Amazonian forest. In addition to being smaller and produced in larger numbers than those of A. aculeatum, A. maripa seeds also presented a substantially lower amount of nutritional reserves available for the embryo. However, A. maripa seedlings were found in much higher numbers than those of A. aculeatum. The results suggest that, within the spatial scale considered, the seed rain of A. maripa is more restricted to the area surrounding around reproductive conspecifics than that of A. aculeatum. Furthermore, in comparison with those of A. aculeatum, the smaller seeds of A. maripa might be less attractive to scatterhoarding rodents (e.g. Dasyprocta aguti. The pattern observed emphasizes the importance of scatterhoarding rodents as dispersers of large-seeded plant species in Neotropical forests.

  6. Arborescent palm seed morphology and seedling distribution.

    Science.gov (United States)

    Salm, Rodolfo

    2005-11-01

    This study examines how the seed morphology of two large arborescent palms, Attalea maripa (Aubl.) Mart. and Astrocaryum aculeatum G. Mey, may affect their seed shadow in a seasonally dry Amazonian forest. In addition to being smaller and produced in larger numbers than those of A. aculeatum, A. maripa seeds also presented a substantially lower amount of nutritional reserves available for the embryo. However, A. maripa seedlings were found in much higher numbers than those of A. aculeatum. The results suggest that, within the spatial scale considered, the seed rain of A. maripa is more restricted to the area surrounding around reproductive conspecifics than that of A. aculeatum. Furthermore, in comparison with those of A. aculeatum, the smaller seeds of A. maripa might be less attractive to scatterhoarding rodents (e.g. Dasyprocta aguti). The pattern observed emphasizes the importance of scatterhoarding rodents as dispersers of large-seeded plant species in Neotropical forests.

  7. Mammal Hunting in the Special Use Zone and Buffer Tingo Maria National Park, Huánuco, Peru

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    Fiorella Nasha Gonzales Guillén

    2014-12-01

    Full Text Available Between the months of August to November 2011 were conducted 42 semi-structured interviews to assess the hunting of mammals in areas of special purpose (ZUE and buffer (ZA National Park Tingo María surveys. The results indicate that 43% of the population practiced hunting as a secondary activity, the main smallholder agriculture. The methodology used for hunting are the "tramperas" while the hunting is often 2-3 times a month. Hunting is more common after the wet season, it is selective and responds to the taste of meat that an economic need. Among the most hunted mammals include agouti Dasyprocta sp. and picuro Cuniculus paca, while animals higher biomass as the peccary Pecari tajacu are rare in the area, so it is recommended to increase the control of hunting of vulnerable species in the villages which are inside and in the vicinity of the Park.

  8. Zygomycetes from herbivore dung in the ecological reserve of Dois Irmãos, Northeast Brazil

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    André Luiz Cabral Monteiro de Azevedo Santiago

    2011-03-01

    Full Text Available Thirty-eight taxa of Zygomycetes distributed in 15 genera were recorded from tapir (Tapirus terrestris, camel (Camelus bactrianus, horse (Equus caballus, deer (Cervus elaphus, agouti (Dasyprocta aguti, donkey (Equus asinus, llama (Llama glama and waterbuck (Kobus ellipsiprymnus dung collected at the Reserva Ecológica de Dois Irmãos located in Recife, State of Pernambuco, Northeast Brazil. The samples were collected on a monthly basis from June 2005 to May 2006, taken to the laboratory and incubated in moist chambers. Higher number of taxa was observed in the excrements of tapir, followed by deer and donkey. The highest number of species was detected for Mucor, followed by Pilobolus. Statistical analyses showed significant differences in richness of Zygomycetes taxa between the herbivore dung types. Differences of species composition, however, were weak. Seasonality influenced the Zygomycetes species composition but not its richness. Variations in taxa composition between ruminants and non-ruminants dung were non significant.

  9. Fatty acids composition of fruits of selected Central European sedges (Carex L. Cyperaceae

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    Janyszek, Magdalena

    2010-06-01

    Full Text Available Fatty acids in the fruits of 13 sedge species (Carex L., Cyperaceae were analyzed. The oil contents in the fruits of the studied sedges ranged from 3.73 and 46.52%. In the studied fruit oils 14 different fatty acids were identified. The main unsaturated fatty acids were: linoleic, α-linolenic, oleic, oleopalmitic n-7; oleopalmitic n-9, octadecenic, and eicosenoic acids. The following acids were found in the greatest quantities: linoleic, oleic, α-linolenic and palmitic acids. Based on the fatty acid composition, studied taxa can be divided in two groups. The first group (C. flava, C. pseudocyperus, C. riparia, C. leporina is a very good source of linoleic acid. The second group, including the remaining species, is a good source of α-linolenic acid. The highest oleic acid contents were observed in C. vulpina. The studied material has shown a low concentration of saturated fatty acids, among which palmitic acid was the main one.Results of the analyses allow for the inclusion of the studied species among plants whose fruits are characterized by a high content of unsaturated fatty acids.Los ácidos grasos de frutos de 13 especies de juncos (Carex L., Cyperaceae fueron analizados. El contenido de aceite en los frutos de juncos estudiados vario desde un 3.73 a un 46.52%. En los aceites de los frutos estudiados fueron identificados 14 ácidos grasos diferentes. Los principales ácidos grasos insaturados fueron los ácidos linoleico, α-linolenico, oleico, n-7 palmitoleico, n-9 palmitoleico, octadecenoico y eicosanoico. Los siguientes ácidos grasos fueron encontrados en mayor cantidad: ácido linoleico, ácido oleico, ácido α-linolenico, y ácido palmítico. Basado en la composición de ácidos grasos, las especies estudiadas pueden ser divididas en dos grupos. El primer grupo (C. flava, C. pseudocyperus, C. riparia, C. leporina es una muy buena fuente de ácido linoleico. El segundo grupo, que incluye las especies restantes, es una buena fuente

  10. Illustrations and studies in Neotropical Orchidaceae. 6. The Lepanthes guatemalensis group (Pleurothallidinae in Costa Rica

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    Pupulin, Franco

    2014-06-01

    Full Text Available We revise and characterize the group of species close to Lepanthes guatemalensis. The group comprises eight species in Costa Rica. Three new species are described and illustrated. Lepanthes durikäensis is distinguished by the non resupinate flowers, the lateral sepals ovate with the apical tails diverging, the lower lobe of petals lanceolate-subfalcate, up-curved and the pinkish column. Lepanthes leporina is recognized by the resupinate flowers with yellow sepals, faintly suffused with red, the petals violet, the lip orange, the bifid synsepal with the apices of the lateral sepals not forming tails, the lateral sepals subequal to the dorsal sepal, the petals markedly convex with the upper lobe elliptic-lanceolate and the lobes of the lip connivent at apex. Lepanthes sanctiorum is characterized by the small plants less than 1.1 cm tall, the short peduncle less than 10 mm long, the petals as wide as the lip length and the blades of the lip distinctly diverging at apex. All the species are described and illustrated on the basis of Costa Rican material. A key to the species of the group is provided.Revisamos y caracterizamos el grupo de especies cercanas a Lepanthes guatemalensis. El grupo está compuesto por ocho especies en Costa Rica. Se describen e ilustran tres especies nuevas. Lepanthes durikäensis se caracteriza por las flores no resupinadas, los sépalos laterales ovados, con las colas apicales divergentes, el lóbulo inferior de los pétalos lanceolado-subfalcado, con curvatura hacia arriba y la columna rosada. Lepanthes leporina es reconocida por las flores resupinadas, los sépalos amarillos y ligeramente teñidos de rojo, los pétalos violeta, el labelo naranja, el sinsépalo bífido con los ápices de los sépalos laterales que no forman colas, los sépalos laterales subiguales al sépalo dorsal, los pétalos marcadamente convexo con el lóbulo superior elíptico-lanceolado y los lóbulos del labelo conniventes en el ápice. Lepanthes

  11. 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. PMID:23593236

  12. Why can't rodents vomit? A comparative behavioral, anatomical, and physiological study.

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    Charles C Horn

    Full Text Available 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.

  13. 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.

  14. Protocolo para la obtención de un Concentrado Autólogo de Plaquetas en conejos: estudio piloto

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    A. F. Bonilla-Gutiérrez

    2017-01-01

    Full Text Available Una de las principales dificultades que se presenta en la práctica quirúrgica es el restablecimiento de la integridad de los tejidos afectados por la patología o por la técnica quirúrgica implementada para su resolución. Actualmente se desarrollan técnicas y tratamientos enfocados en mejorar los procesos cicatrizales y favorecer la regeneración de los tejidos; uno de ellos es el Concentrado Autólogo de Plaquetas (CAP. El objetivo del presente estudio fue evaluar la técnica de colecta y procesamiento de la sangre para obtener CAP en un modelo experimental lagomorfo utilizando conejos machos de la raza Nueva Zelanda (n = 10 con pesos comprendidos entre 3 y 3,8 kg. La sangre de cada animal fue obtenida por punción de la vena yugular, colectada en tubos con citrato de sodio y centrifugada a 120 g durante 5 minutos. Después del proceso de centrifugación los niveles de eritrocitos, leucocitos y plaquetas presentaron diferencias estadísticamente significativas (P < 0,05 en comparación con la sangre completa. Los resultados de este estudio, permiten concluir que es factible la elaboración de un CAP para la especie leporina, obteniendo plaquetas sin alteración de la morfología a partir de un ciclo de centrifugación.

  15. Fatty acids composition of fruits of selected Central European sedges (Carex L. Cyperaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Bogucka-Kocka, A.; Janyszek, M.

    2010-07-01

    Fatty acids in the fruits of 13 sedge species (Ca rex L., Cyperaceae) were analyzed. The oil contents in the fruits of the studied sedges ranged from 3.73 and 46.52%. In the studied fruit oils 14 different fatty acids were identified. The main unsaturated fatty acids were: linoleic, a-linolenic, oleic, oleo palmitic n-7; oleo palmitic n-9, octadecenic, and eicosenoic acids. The following acids were found in the greatest quantities: linoleic, oleic, a-linolenic and palmitic acids. Based on the fatty acid composition, studied taxa can be divided in two groups. The first group (C. flava, C. pseudocyperus, C. riparia, C. leporina) is a very good source of linoleic acid. The second group, including the remaining species, is a good source of a-linolenic acid. The highest oleic acid contents were observed in C. vulpina. The studied material has shown a low concentration of saturated fatty acids, among which palmitic acid was the main one.Results of the analyses allow for the inclusion of the studied species among plants whose fruits are characterized by a high content of unsaturated fatty acids. (Author)

  16. 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.

  17. 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.

  18. 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...

  19. 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.

  20. Experimental model of double wounds on the rats back , in order to study the skin cicatrization process on rat treated with cellulose coat

    OpenAIRE

    Lecy Marcondes Cabral; Lydia Masako Ferreira; Manuel de Jesus Simões; Oswaldo Alves Mora

    2003-01-01

    To the present study were used males rats (Rattus Norvegicus, var. Albinus, Rodentia Mammalia) EPM-1 Wistar, which came from Biotério Central da UNIFESP-EPM. Each animal was submitted to two wound of circular shape, made with a "punch", with superficial cuts of 2 cm diameter; located on medium line of dorsal region. In the present study, one wound was re-covered with the cellulose coat and the other serves as a control. This experimental form, makes it possible to us realize different studies...

  1. Mammal (Mammalia Fauna of Kapıdağ Peninsula

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    Erdem HIZAL

    2008-01-01

    Full Text Available The number of studies on mammals of Kapıdag Peninsula is insufficent. The present study is based on mammal species collected and observed in Kapıdag Peninsula. Kapıdag Peninsula was visited as a total of 226 days between 2001-2007. Field collections yielded 32 mammal species from 6 orders: Insectivora (5, Chiroptera (9,Lagomorpha (1, Rodentia (7, Carnivora (7, Artiodactyla (3. Of the species recorded in this study are rare for Kapıdag Peninsula: Lynx lynx and Felis silvestris.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Mitigación de daños provocados por fauna silvestre en cultivos agrícolas en un bosque montano de Bolivia

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    Eddy Pérez L.

    2014-12-01

    Full Text Available El daño causado por fauna silvestre en cultivos agrícolas es una de las causas principales de conflicto dentro y fuera de áreas protegidas. Para un adecuado manejo del conflicto se requieren evaluaciones del daño y de la aplicación de distintos métodos de mitigación. El objetivo del trabajo fue evaluar la efectividad de prácticas agroculturales y cacería de control, para reducir daños por vertebrados silvestres en cultivos agrícolas anuales en el PN ANMI Cotapata. Se trabajó en siete parcelas con prácticas agroculturales, cuatro parcelas con cacería de control y cinco parcelas control, registrándose el tipo y densidad de cultivo, frecuencia de visitas de especies dañinas a huelleros, plantación perdida, especies responsables y biomasa de cosecha. Los resultados muestran que las especies más frecuentes fueron: Dasyprocta sp. y Dasypus novemcinctus, siendo estas 1.6 veces más frecuentes en parcelas con prácticas agroculturales. En promedio se perdió 7.3% de la plantación en parcelas agroculturales, 4.6% en parcelas sujetas a cacería de control, y 27.6% en parcelas control. Las principales especies responsables de las pérdidas fueron: P. tajacu, seguido por Dasyprocta sp. y S. apella. A través de estas estrategias de manejo, redujo las pérdidas en >50%, con lo cual se considera que los métodos puestos a prueba son útiles y se recomienda utilizarlos a gran escala con la consideración de que podría ser necesario innovar cada cierto tiempo, pues los animales silvestres tienden a acostumbrarse a los métodos de ahuyentamiento en ejecución.

  8. Diversidad de mamíferos terrestres de talla grande y media de una selva subcaducifolia del noreste de Oaxaca, México Diversity of large and medium sized land mammals of a subcaducifolious tropical forest of north eastern of Oaxaca, Mexico

    Directory of Open Access Journals (Sweden)

    Gabriela Pérez-Irineo

    2012-03-01

    Full Text Available El estado de Oaxaca en el sureste de México alberga una biodiversidad extraordinaria. Sin embargo, las actividades humanas han propiciado alteraciones considerables, incluida la disminución de diferentes ambientes naturales, especialmente de los bosques tropicales; por ello es importante documentar la diversidad de estos ambientes, así como su respuesta a las transformaciones antropocéntricas. Este trabajo tiene como objetivo estimar la diversidad de mamíferos terrestres en una selva mediana en el noreste del estado de Oaxaca, México. Se recorrieron 3 senderos para la búsqueda de rastros, captura de organismos, avistamientos y fototrampeo de septiembre de 2007 a agosto de 2008. Se registraron 15 especies de 6 órdenes, 11 familias y 14 géneros, entre ellas 7 nuevas para la región. Las especies más abundantes fueron Nasua narica, Pecari tajacu, Dasyprocta mexicana, Cuniculus paca y Leopardus pardalis. A pesar de presentar un índice de diversidad bajo con respecto a otros estudios comparables, la presencia de especies consideradas en riesgo por la legislación mexicana, como L. pardalis, L. wiedii, Eira barbara y Tamandua mexicana hacen a la zona valiosa para la conservación de la diversidad en la región.The state of Oaxaca, in southeast Mexico is home to an extraordinary biodiversity. But human activities have led to significant changes, including reduction of different natural habitats, especially tropical forests, so it is important to document the diversity of these environments, and their response to the anthropocentric changes. Therefore, this study aimed to estimate the diversity of terrestrial mammals in a tropical forest in northeastern of the state of Oaxaca, Mexico. Three transects were walked to search for tracks, catches of organisms, sightings, and phototrapping from September 2007 to August 2008. There were recorded 15 species of 6 orders, 11 families, and 14 genera, 7 of this not previously known in the region. The

  9. A monograph of Otidea (Pyronemataceae, Pezizomycetes).

    Science.gov (United States)

    Olariaga, I; Van Vooren, N; Carbone, M; Hansen, K

    2015-12-01

    The easily recognised genus Otidea is subjected to numerous problems in species identification. A number of old names have undergone various interpretations, materials from different continents have not been compared and misidentifications occur commonly. In this context, Otidea is monographed, based on our multiple gene phylogenies assessing species boundaries and comparative morphological characters (see Hansen & Olariaga 2015). All names combined in or synonymised with Otidea are dealt with. Thirty-three species are treated, with full descriptions and colour illustrations provided for 25 of these. Five new species are described, viz. O. borealis, O. brunneoparva, O. oregonensis, O. pseudoleporina and O. subformicarum. Otidea cantharella var. minor and O. onotica var. brevispora are elevated to species rank. Otideopsis kaushalii is combined in the genus Otidea. A key to the species of Otidea is given. An LSU dataset containing 167 sequences (with 44 newly generated in this study) is analysed to place collections and determine whether the named Otidea sequences in GenBank were identified correctly. Fourty-nine new ITS sequences were generated in this study. The ITS region is too variable to align across Otidea, but had low intraspecific variation and it aided in species identifications. Thirty type collections were studied, and ITS and LSU sequences are provided for 12 of these. A neotype is designated for O. cantharella and epitypes for O. concinna, O. leporina and O. onotica, along with several lectotypifications. The apothecial colour and shape, and spore characters are important for species identification. We conclude that to distinguish closely related or morphologically similar species, a combination of additional features are needed, i.e. the shape of the paraphyses, ectal excipulum structure, types of ectal excipulum resinous exudates and their reactions in Melzer's reagent and KOH, tomentum and basal mycelium colours and exudates. The KOH reaction of

  10. On the mammals collected by Friedrich Sellow in Brazil and Uruguay (1814-1831), with special reference to the types and their provenance.

    Science.gov (United States)

    Garbino, Guilherme S T; Nogueira, Marcelo R

    2017-01-17

    From 1814 to 1831, the Prussian naturalist Friedrich Sellow collected 263 mammals in Brazil and Uruguay. Upon receiving the specimens, the curator of the Berlin Zoological Museum, Martin Lichtenstein, removed the original labels and replaced with ones containing more generalized locations. As a consequence, several type specimens have now dubious type localities. We examined these types as well as geographically restricted mammals collected by Sellow. In some cases, there are inconsistencies between the specimen label and the collection catalog regarding the collecting locality. We conclude that the locality information on the lectotype of the tent-making bat Uroderma bilobatum is mistakenly identified, and therefore, we restrict it to "eastern Brazil". We designate a lectoype for Azara's agouti, Dasyprocta azarae, and restrict its type locality to the region travelled by Sellow in São Paulo. Although there are no recent records of the woolly giant rat, Kunsia tomentosus, from its type locality, the species may have been recently extirpated from the area. Two primate specimens supposedly collected by Sellow, a silvery marmoset, Mico argentatus, and a black tamarin, Saguinus niger, occur only in the Amazonia of northern Brazil, outside the route travelled by the naturalist, and are more likely to have been collected by Sieber. Our investigations stress the importance of collecting vouchers for verifying species occurrence records and establishing a solid taxonomy.

  11. Le mini-élevage, son développement villageoiset l'action de BEDIM

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    Jacques Hardouin

    1997-01-01

    Full Text Available Minilivestock, village development and the role of BEDIM.Minilivestock encompasses all animals of small site, and little-known in terras of production but usable as food, feed or revenues if not eaten. Sustainable breeding becomes possible, and should progressively replace uncontrolled gathering in the wild. Amongst vertebrates, an important meat supply is based on edible rodents like Thryonomys, Cricetomys, Xerus, Atherurus, Tenrec; Hydrochoerus, Dasyprocta, Myocastor, Capromys, Dolichotis, Agouti, etc. The saine applies to the guinea-pig Cavia porcellus and to frogs. Invertebrates farming is also practised through breeding of maggots, termites, butterflies (pupae and adults for consumption or sale; giant snails are also highly appreciated in many African countries. Minilivestock development is usually a back-yard activity, hence its interest as it relies on local species, substrates and raw materials for infrastructure. The demand for minilivestock product is high but there is still reluctance often from the official authorities, unfortunately. However minilivestock is not an utopia, and a country like Papua-New-Guinea, which bas officially adopted minilivestock production as a tool to help to develop remote villages, is an excellent example of success

  12. Hunting and use of terrestrial fauna used by Caiçaras from the Atlantic Forest coast (Brazil

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    Alves Rômulo RN

    2009-11-01

    Full Text Available Abstract Background The Brazilian Atlantic Forest is considered one of the hotspots for conservation, comprising remnants of rain forest along the eastern Brazilian coast. Its native inhabitants in the Southeastern coast include the Caiçaras (descendants from Amerindians and European colonizers, with a deep knowledge on the natural resources used for their livelihood. Methods We studied the use of the terrestrial fauna in three Caiçara communities, through open-ended interviews with 116 native residents. Data were checked through systematic observations and collection of zoological material. Results The dependence on the terrestrial fauna by Caiçaras is especially for food and medicine. The main species used are Didelphis spp., Dasyprocta azarae, Dasypus novemcinctus, and small birds (several species of Turdidae. Contrasting with a high dependency on terrestrial fauna resources by native Amazonians, the Caiçaras do not show a constant dependency on these resources. Nevertheless, the occasional hunting of native animals represents a complimentary source of animal protein. Conclusion Indigenous or local knowledge on native resources is important in order to promote local development in a sustainable way, and can help to conserve biodiversity, particularly if the resource is sporadically used and not commercially exploited.

  13. [Wildlife damage mitigation in agricultural crops in a Bolivian montane forest].

    Science.gov (United States)

    Perez, Eddy; Pacheco, Luis F

    2014-12-01

    Wildlife is often blamed for causing damage to human activities, including agricultural practices and the result may be a conflict between human interests and species conservation. A formal assessment of the magnitude of damage is necessary to adequately conduct management practices and an assessment of the efficiency of different management practices is necessary to enable managers to mitigate the conflict with rural people. This study was carried out to evaluate the effectiveness of agricultural management practices and controlled hunting in reducing damage to subsistence annual crops at the Cotapata National Park and Natural Area of Integrated Management. The design included seven fields with modified agricultural practices, four fields subjected to control hunting, and five fields held as controls. We registered cultivar type, density, frequency of visiting species to the field, crops lost to wildlife, species responsible for damage, and crop biomass. Most frequent species in the fields were Dasyprocta punctata and Dasypus novemcinctus. Hunted plots were visited 1.6 times more frequently than agriculturally managed plots. Crop lost to wildlife averaged 7.28% at agriculturally managed plots, 4.59% in plots subjected to hunting, and 27.61% in control plots. Species mainly responsible for damage were Pecari tajacu, D. punctata, and Sapajus apella. We concluded that both management strategies were effective to reduce damage by >50% as compared to unmanaged crop plots.

  14. Seed dispersal, plant recruitment and spatial distribution of Bactris acanthocarpa Martius (Arecaceae) in a remnant of Atlantic forest in northeast Brazil

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    Silva, Maria G.; Tabarelli, Marcelo

    2001-12-01

    Seed dispersal ecology of Bactris acanthocarpa Mart. (Arecaceae), an Atlantic forest understory palm, was investigated during two years as an attempt to test the following predictions: (i) seeds of Bactris are dispersed by mammals and large-gaped birds; (ii) Bactris benefits from seed dispersal in terms of seed predation avoidance, improvement of seed germination and seedling survival; and (iii) spatial distribution of adults is related to patterns of seed dispersal. The study was conducted at Dois Irmãos Reserve, a 387.4-ha reserve of Atlantic forest in northeastern Brazil (8º S-35º W). Black-rumped agoutis ( Dasyprocta prymnolopha) and Guianan squirrels ( Sciurus aestuans) were identified as the seed dispersers/predators, moving seeds short distances ( 4 m away in contrast to 96% of seedlings that occurred concentrated within 4 m from adults (77% under the palm crowns). Here, we present evidence that spatial distribution of B. acanthocarpa is partly due to low rates of seed removal, short-distance seed dispersal by agoutis and squirrels, and early seedling mortality associated with presence of seedlings under palm crowns.

  15. Natural regeneration and dispersion of seeds of the imbuzeiro (spondias tuberosa Arruda in the Pernambuco hinterland, Brazil

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    Luiza Teixeira de Lima Brito

    2009-08-01

    Full Text Available This work had as objective to evaluate the dispersion of the seeds of imbuzeiro (Spondias tuberosa Arruda for the animals and the survival of plants in caatinga. The work was carried out in the period from October of 2002 to December of 2005 in degraded and native area of caatinga. They had been selected to perhaps, 16 plants of imbuzeiro, being eight plants in each area. In each plant twelve transectos of 1 m of width for 25 m had been demarcated, where the seeds found in the young ground and plants. The used experimental delineation was block-type to perhaps in factorial project 5 x 2, with four repetitions. 1003.5 seeds.m-2 had been, on average, in the first units you show of caatinga native and in caatinga degraded, it was observed, on average, 31.25 seeds m-2. In the native area of caatinga they had been registered 2.5 plants m-2, on average, in the first units you show during the rainy station. The dispersive ones of the seeds observed in the native area of catinga had been the deer-catingueiro (Mazama gouazoubira, the cotia (Dasyprocta cf. prymnolopha, caititu (Tayassu tajacu, the fox (Dusicyon thous, the teiú (Tupinambis merianae, the tatu-peba (Euphractus sexcinctus of the guará (Procyon cancrivous the area of caatinga e na área de caatinga degraded the sheep (Capra hircus.Key-words: rain, tree, seedlings, emergency, germination.

  16. Novel piroplasmid and Hepatozoon organisms infecting the wildlife of two regions of the Brazilian Amazon

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    Herbert S. Soares

    2017-08-01

    Full Text Available During 2009–2012, wild animals were sampled in two areas within the Amazon biome of Brazil, in the states of Mato Grosso and Pará. Animal tissues and blood were molecularly tested for the presence of Piroplasmida (genera Babesia, Theileria, Cytauxzoon or Hepatozoon DNA. Overall, 181 wild animals comprising 36 different species (2 reptiles, 5 birds, and 29 mammals were sampled. The following Piroplasmida agents were detected: Cytauxzoon felis in one ocelot (Leopardus pardalis, Theileria cervi in two red brocket deer (Mazama americana, Theileria spp. in three nine-banded-armadillos (Dasypus novemcinctus, one agouti (Dasyprocta sp., and four lowland pacas (Cuniculus paca, Babesia spp. in one common opossum (Didelphis marsupialis and one white-lipped peccary (Tayassu pecari. The following Hepatozoon agents were detected: Hepatozoon sp. (possibly Hepatozoon caimani in three spectacled caimans (Caiman crocodilus, Hepatozoon felis in an ocelot (Leopardus pardalis, and Hepatozoon spp. in one scorpion mud turtle (Kinosternon scorpioides and one lowland paca (Cuniculus paca. Phylogenetic analyses inferred by the 18S rRNA gene partial sequences supported these results, highlighting at least five novel Piroplasmida agents, and two novel Hepatozoon agents. This study screened the presence of tick-borne protozoa in a number of wildlife species from the Amazon for the first time. Our results indicate that a variety of genetically distinct Piroplasmida and Hepatozoon organisms circulate under natural conditions in the Amazonian wildlife.

  17. Wild Rodents as Experimental Intermediate Hosts of Lagochilascaris minor Leiper, 1909

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    Julieta Machado Paçô

    1999-07-01

    Full Text Available A total of 25 specimens of Cavia porcellus (guinea pig, 5 Dasyprocta agouti (agouti, and 22 Calomys callosus (vesper mice were inoculated with infective eggs of Lagochilascaris minor. The inoculum was prepared with embryonated eggs and orally administered to each individual animal through an esophagus probe. In parallel, 100 specimens of Felis catus domesticus were individually fed with 55-70 nodules containing 3rd-stage larvae encysted in tissues of infected rodents. Animals were examined and necropsied at different time intervals. The migration and encystment of L3 larva was observed in viscera, skeletal muscle, adipose and subcutaneous tissues from all rodents. Adult worms localized at abscesses in the cervical region, rhino, and oropharynx were recovered from domestic cats inoculated with infected rodent tissues. Through this study we can conclude that: (1 wild rodents act as intermediate hosts, characterizing this ascarid heteroxenic cycle; (2 in natural conditions rodents could possibly act as either intermediate hosts or paratenic hosts of Lagochilascaris minor; (3 despite the occurrence of an auto-infecting cycle, in prime-infection of felines (definite hosts the cycle is only completed when intermediate hosts are provided; and (4 in the wild, rodents could serve as a source of infection for humans as they are frequently used as food in regions with the highest incidence of human lagochilascariasis.

  18. 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.

  19. 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.

  20. 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

  1. MÉTODOS DIRETOS E INDIRETOS PARA O REGISTRO DE MAMÍFEROS NO FRAGMENTO DE MATA ATLÂNTICA - UNIVAP, CAMPUS URBANOVA

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    Caio Ferreira

    2017-05-01

    Full Text Available A Mata Atlântica é um dos biomas mais ameaçados do Brasil e o estabelecimento de áreas protegidas é uma das formas para se conservar este bioma. Para legalizar uma unidade de conservação, é preciso conhecer a fauna e flora local. O trabalho objetiva inventariar a mastofauna terrestre em um fragmento de Mata Atlântica, localizado na divisa entre os municípios de Jacareí e São José dos Campos, SP. Foram utilizados dois métodos distintos: método direto (transecto linear e método indireto (parcela de areia. Como resultados foram registrados oito táxons distribuídos em quatro ordens: Cingulata, Carnivora, Didelphimorphia e Rodentia. Os dois métodos foram eficientes para o registro da mastofauna presente na área de estudo.

  2. 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.

  3. Discussion to several tapeworm species from the families Hymenolepididae, Anoplocephalidae and Davaineidae parasitizing rodents and man

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    František Tenora

    2004-01-01

    Full Text Available With the more recent knowledge, the hypothesis by Joyeux and Baer (1929 is consulted: “... most of rarer species of tapeworms occurring in man are probably parasites of other mammals, specially of Rodentia .....“. In connection with that, the host specificity in several species from the families Hymenolepididae, Anoplocephalidae and Davaineidae is discussed. So far parasites of rodents are concerned, they are the species Rodentolepis straminea, R. fraterna, Hymenolepis diminuta, H. pseudodiminuta, H. hibernia and Inermicapsifer arvicanthidis. So far parasites of man are concerned, they are the species Rodentolepis nana, Hymenolepis flavopunctata and Inermicapsifer madagascariensis. Attention is drawn also to discrepancies in the opinions published on the views of hosts’ specificity or of zoogeographical distribution of several species from the family Davaineidae.

  4. Epidemiological role of a rodent in Morocco: Case of cutaneous leishmaniasis

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    Mohamed Echchakery

    2015-08-01

    Full Text Available Commensal rodents as well as wild ones may present a potential risk to public health. They are reservoirs or vectors of many pathogens. This review provides an update on their epidemiological role in the spread of leishmaniasis in Morocco. In Morocco, the order Rodentia is represented by 7 families and 32 species of which Rattus norvegicus, Psammomys obesus, Mastomys erythrolecus, Meriones shawi, Meriones crassus and Meriones libycus are considered reservoirs of leishmaniasis in Asia, Midle East and Africa. With the aim to define the extent of zoonotic leishmaniasis risk in Morocco, we represent and discuss the geographical distribution of these potential reservoirs in relation to that of Phlebotomus papatasi, proven vector of cutaneous leishmaniasis by Leishmania major in Morocco.