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Sample records for murid rodent species

  1. Xenopsylla spp. (Siphonaptera: Pulicidae) in murid rodents from the Canary Islands: an update.

    Science.gov (United States)

    Sánchez, S; Gómez, M S

    2012-11-01

    The geographical and host distributions of Xenopsylla fleas parasitizing murid rodents on the Canary Islands have been reported. Three Xenopsylla species, X. cheopis, X. brasiliensis and X. guancha, have been detected on two rodents species, Mus musculus and Rattus rattus. X. guancha has been the most prevalent species detected, specifically on M. musculus, the most abundant rodent, but it has been detected only on three eastern islands, where the species is endemic. X. cheopis has been shown to be the most widely distributed species throughout the archipelago and the species most frequently found on R. rattus. X. brasiliensis has been shown to be the least prevalent Xenopsylla species, with the lowest geographical distribution on the Canary Islands and focused only on R. rattus. The detection of both X. cheopis and X. brasiliensis on the island of Lanzarote, and of X. guancha on the island of Fuerteventura and the islet of La Graciosa represents the first report of these species on those particular Canary Islands.

  2. Xenopsylla spp. (Siphonaptera: Pulicidae in murid rodents from the Canary Islands: An update

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    Sánchez S.

    2012-11-01

    Full Text Available The geographical and host distributions of Xenopsylla fleas parasitizing murid rodents on the Canary Islands have been reported. Three Xenopsylla species, X. cheopis, X. brasiliensis and X. guancha, have been detected on two rodents species, Mus musculus and Rattus rattus. X. guancha has been the most prevalent species detected, specifically on M. musculus, the most abundant rodent, but it has been detected only on three eastern islands, where the species is endemic. X. cheopis has been shown to be the most widely distributed species throughout the archipelago and the species most frequently found on R. rattus. X. brasiliensis has been shown to be the least prevalent Xenopsylla species, with the lowest geographical distribution on the Canary Islands and focused only on R. rattus. The detection of both X. cheopis and X. brasiliensis on the island of Lanzarote, and of X. guancha on the island of Fuerteventura and the islet of La Graciosa represents the first report of these species on those particular Canary Islands.

  3. Thermal energetics of the New-Guinean moss-forest rat (Rattus niobe) in comparison with other tropical murid rodents.

    Science.gov (United States)

    Genoud, Michel

    2014-04-01

    The thermal energetics of rodents from cool, wet tropical highlands are poorly known. Metabolic rate, body temperature and thermal conductance were measured in the moss-forest rat, Rattus niobe (Rodentia), a small murid endemic to the highlands of New Guinea. These data were evaluated in the context of the variation observed in the genus Rattus and among tropical murids. In 7 adult R. niobe, basal metabolic rate (BMR) averaged 53.6±6.6mLO2h(-1), or 103% of the value predicted for a body mass of 42.3±5.8g. Compared to other species of Rattus, R. niobe combines a low body temperature (35.5±0.6°C) and a moderately low minimal wet thermal conductance cmin (5.88±0.7mLO2h(-1)°C(-1), 95% of predicted) with a small size, all of which lead to reduced energy expenditure in a constantly cool environment. The correlations of mean annual rainfall and temperature, altitude and body mass with BMR, body temperature and cmin were analyzed comparatively among tropical Muridae. Neither BMR, nor cmin or body temperature correlated with ambient temperature or altitude. Some of the factors which promote high BMR in higher latitude habitats, such as seasonal exposure to very low temperature and short reproductive season, are lacking in wet montane tropical forests. BMR increased with rainfall, confirming a pattern observed among other assemblages of mammals. This correlation was due to the low BMR of several desert adapted murids, while R. niobe and other species from wet habitats had a moderate BMR. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Distribution and genetic variation of hymenolepidid cestodes in murid rodents on the Canary Islands (Spain).

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    Foronda, Pilar; López-González, Mercedes; Hernández, Mariano; Haukisalmi, Voitto; Feliu, Carlos

    2011-09-26

    In the Canary Islands there are no previous data about tapeworms (Cestoda) of rodents. In order to identify the hymenolepidid species present in these hosts, a survey of 1,017 murine (349 Rattus rattus, 13 Rattus norvegicus and 655 Mus musculus domesticus) was carried out in the whole Archipelago. Molecular studies based on nuclear ITS1 and mitochondrial COI loci were performed to confirm the identifications and to analyse the levels of genetic variation and differentiation. Three species of hymenolepidids were identified: Hymenolepis diminuta, Rodentolepis microstoma and Rodentolepis fraterna. Hymenolepis diminuta (in rats) and R. microstoma (in mice) showed a widespread distribution in the Archipelago, and R. fraterna was the least spread species, appearing only on five of the islands. The hymenolepidids found on Fuerteventura, Lanzarote and La Graciosa were restricted to one area. The COI network of H. diminuta showed that the haplotypes from Lanzarote and Fuerteventura are the most distant with respect to the other islands, but clearly related among them. Founder effects and biotic and abiotic factors could have played important role in the presence/absence of the hymenolepidid species in determined locations. The haplotypes from the eastern islands (Fuerteventura and Lanzarote) seem to have shared an ancestral haplotype very distant from the most frequent one that was found in the rest of the islands. Two colonization events or a single event with subsequent isolation and reduced gene flow between western-central and eastern islands, have taken place in the Archipelago. The three tapeworms detected are zoonotic species, and their presence among rodents from this Archipelago suggests a potential health risk to human via environmental contamination in high risk areas. However, the relatively low prevalence of infestations detected and the focal distribution of some of these species on certain islands reduce the general transmission risk to human.

  5. Distribution and genetic variation of hymenolepidid cestodes in murid rodents on the Canary Islands (Spain

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    Feliu Carlos

    2011-09-01

    Full Text Available Abstract Background In the Canary Islands there are no previous data about tapeworms (Cestoda of rodents. In order to identify the hymenolepidid species present in these hosts, a survey of 1,017 murine (349 Rattus rattus, 13 Rattus norvegicus and 655 Mus musculus domesticus was carried out in the whole Archipelago. Molecular studies based on nuclear ITS1 and mitochondrial COI loci were performed to confirm the identifications and to analyse the levels of genetic variation and differentiation. Results Three species of hymenolepidids were identified: Hymenolepis diminuta, Rodentolepis microstoma and Rodentolepis fraterna. Hymenolepis diminuta (in rats and R. microstoma (in mice showed a widespread distribution in the Archipelago, and R. fraterna was the least spread species, appearing only on five of the islands. The hymenolepidids found on Fuerteventura, Lanzarote and La Graciosa were restricted to one area. The COI network of H. diminuta showed that the haplotypes from Lanzarote and Fuerteventura are the most distant with respect to the other islands, but clearly related among them. Conclusions Founder effects and biotic and abiotic factors could have played important role in the presence/absence of the hymenolepidid species in determined locations. The haplotypes from the eastern islands (Fuerteventura and Lanzarote seem to have shared an ancestral haplotype very distant from the most frequent one that was found in the rest of the islands. Two colonization events or a single event with subsequent isolation and reduced gene flow between western-central and eastern islands, have taken place in the Archipelago. The three tapeworms detected are zoonotic species, and their presence among rodents from this Archipelago suggests a potential health risk to human via environmental contamination in high risk areas. However, the relatively low prevalence of infestations detected and the focal distribution of some of these species on certain islands reduce

  6. A redescription of Protospirura muricola Gedoelst, 1916 (Nematoda: Spiruridae), a parasite of murid rodents.

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    Smales, L R; Harris, P D; Behnke, J M

    2009-01-01

    The spirurid nematode Protospirura muricola Gedoelst, 1916 is redescribed from Acomys dimidiatus (Desmarest) from the St Katherine Protectorate, Sinai, Egypt. Egyptian material closely resembled specimens of P. muricola from African mammals re-examined in this study, as well as conforming to published reports of this species. P. muricola with two denticles on each lateral lobe of the pseudolabia and six pairs of postanal papillae is closest to P. pseudomuris Yokohata & Abe, 1989, but can be readily distinguished in having the right spicule shorter than the left. The significance of the characteristics of the head and mouth, and of the male spicules, in characterising Protospirura Seurat, 1914 is evaluated. P. muricola, an African parasite of rodents, appears to have spread globally with synanthropic rat final hosts and possibly with the cosmopolitan dermapteran intermediate host Leucophaea maderae (Fabr.).

  7. Can a native rodent species limit the invasive potential of a non-native rodent species in tropical agroforest habitats?

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    Stuart, Alexander M; Prescott, Colin V; Singleton, Grant R

    2016-06-01

    Little is known about native and non-native rodent species interactions in complex tropical agroecosystems. We hypothesised that the native non-pest rodent Rattus everetti may be competitively dominant over the invasive pest rodent Rattus tanezumi within agroforests. We tested this experimentally by using pulse removal for three consecutive months to reduce populations of R. everetti in agroforest habitat, and assessed over 6 months the response of R. tanezumi and other rodent species. Following removal, R. everetti individuals rapidly immigrated into removal sites. At the end of the study period, R. tanezumi were larger and there was a significant shift in their microhabitat use with respect to the use of ground vegetation cover following the perturbation of R. everetti. Irrespective of treatment, R. tanezumi selected microhabitat with less tree canopy cover, indicative of severely disturbed habitat, whereas R. everetti selected microhabitat with a dense canopy. Our results suggest that sustained habitat disturbance in agroforests favours R. tanezumi, while the regeneration of agroforests towards a more natural state would favour native species and may reduce pest pressure in adjacent crops. In addition, the rapid recolonisation of R. everetti suggests this species would be able to recover from non-target impacts of short-term rodent pest control. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  8. CLIMBING BEHAVIOUR IN THREE AFRICAN RODENT SPECIES ...

    African Journals Online (AJOL)

    These two species, but more no~ ably TIUlllomy8 ... covered by thin wire mesh. Three branches, two with rough bark and the third barkless, were ... Animals were tested during the dark phase of a reversed photoperiod (09hOO-17hOO of the.

  9. MENINGKATKAN SELF-ESTEEM MURID MELALUI TEKNIK STEP BY STEP

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    Er, Lim Xing; Zakaria, Sheridean

    2017-01-01

    Dalam kehidupan dan pergaulan harian, sesetengah murid menghadapi masalah tahap self-esteem yang rendah sehingga mempengaruhi prestasi diri dan keyakinan diri untuk melakukan apa-apa sahaja. Kajian ini dijalankan bertujuan untuk meningkatkan self-esteem murid. Pemilihan peserta kajian adalah berdasarkan hasil temubual, pemerhatian dan borang soal selidik yang dapat mengenal pasti tahap self-esteem murid yang rendah. Peserta kajian terdiri daripada 2 orang murid lelaki Tahun 4 dan seorang muri...

  10. A test of five mechanisms of species coexistence between rodents in ...

    African Journals Online (AJOL)

    A test of five mechanisms of species coexistence between rodents in a southern African savanna. M.R. Perrin, B.P. Kotler. Abstract. The operation of five different mechanisms of species coexistence in a community of rodents was examined in a semi-arid Kalahari savanna in southern Africa. The two most common species ...

  11. Rodent Species Distribution and Hantavirus Seroprevalence in Residential and Forested areas of Sarawak, Malaysia.

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    Hamdan, Nur Elfieyra Syazana; Ng, Yee Ling; Lee, Wei Bin; Tan, Cheng Siang; Khan, Faisal Ali Anwarali; Chong, Yee Ling

    2017-01-01

    Rodents belong to the order Rodentia, which consists of three families in Borneo (i.e., Muridae, Sciuridae and Hystricidae). These include rats, mice, squirrels, and porcupines. They are widespread throughout the world and considered pests that harm humans and livestock. Some rodent species are natural reservoirs of hantaviruses (Family: Bunyaviridae) that can cause zoonotic diseases in humans. Although hantavirus seropositive human sera were reported in Peninsular Malaysia in the early 1980s, information on their infection in rodent species in Malaysia is still lacking. The rodent populations in residential and forested areas in Sarawak were sampled. A total of 108 individuals from 15 species of rodents were collected in residential ( n = 44) and forested ( n = 64) areas. The species diversity of rodents in forested areas was significantly higher (H = 2.2342) compared to rodents in residential areas (H = 0.64715) ( p Sarawak, East Malaysia. The results suggested that hantavirus was not circulating in the studied rodent populations in Sarawak, or it was otherwise at a low prevalence that is below the detection threshold. It is important to remain vigilant because of the zoonotic potential of this virus and its severe disease outcome. Further studies, such as molecular detection of viral genetic materials, are needed to fully assess the risk of hantavirus infection in rodents and humans in this region of Malaysia.

  12. Stochastic seasonality and nonlinear density-dependent factors regulate population size in an African rodent

    DEFF Research Database (Denmark)

    Leirs, Herwig; Steneth, Nils Chr.; Nichols, James D.

    1997-01-01

    , but clear examples of both processes acting in the same population are rare(7,8). Key-factor analysis (regression of population changes on possible causal factors) and time-series analysis are often used to investigate the presence of density dependence, but such approaches may be biased and provide...... no information on actual demographic rates(9,10). Here we report on both density-dependent and density-independent effects in a murid rodent pest species, the multimammute rat Mastomys natalensis (Smith, 1834), using statistical capture-recapture models, Both effects occur simultaneously, but we also demonstrate...

  13. The bioeconomics of controlling an African rodent pest species

    DEFF Research Database (Denmark)

    Skonhoft, Anders; Leirs, Herwig; Andreassen, Harry P

    2006-01-01

    The paper treats the economy of controlling an African pest rodent, the multimammate rat, causing major damage in maize production. An ecological population model is presented and used as a basis for the economic analyses carried out at the village level using data from Tanzania. This model...... incorporates both density-dependent and density-independent (stochastic) factors. Rodents are controlled by applying poison, and the costs are made up of the cost of poison plus the damage to maize production. We analyse how the present-value costs of maize production are affected by various rodent control...

  14. The bioeconomics of controlling an African rodent pest species

    OpenAIRE

    Skonhoft, Anders; Herwig, Leirs; Andreassen, Harry Peter; Mulungu, Loth S. A.; Stenseth, Nils Christian

    2006-01-01

    The paper treats the economy of controlling an African pest rodent, the multimammate rat, causing major damage in maize production. An ecological population model is presented and used as a basis for the economic analyses carried out at the village level using data from Tanzania. This model incorporates both density-dependent and density-independent (stochastic) factors. Rodents are controlled by applying poison, and the economic benefits depend on the income from maize production minus the c...

  15. Effects of rodent species, seed species, and predator cues on seed fate

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    Sivy, Kelly J.; Ostoja, Steven M.; Schupp, Eugene W.; Durham, Susan

    2011-07-01

    Seed selection, removal and subsequent management by granivorous animals is thought to be a complex interaction of factors including qualities of the seeds themselves (e.g., seed size, nutritional quality) and features of the local habitat (e.g. perceived predator risk). At the same time, differential seed selection and dispersal is thought to have profound effects on seed fate and potentially vegetation dynamics. In a feeding arena, we tested whether rodent species, seed species, and indirect and direct predation cues influence seed selection and handling behaviors (e.g., scatter hoarding versus larder hoarding) of two heteromyid rodents, Ord's kangaroo rat ( Dipodomys ordii) and the Great Basin pocket mouse ( Perognathus parvus). The indirect cue was shrub cover, a feature of the environment. Direct cues, presented individually, were (1) control, (2) coyote ( Canis latrans) vocalization, (3) coyote scent, (4) red fox ( Vulpes vulpes) scent, or (5) short-eared owl ( Asio flammeus) vocalization. We offered seeds of three sizes: two native grasses, Indian ricegrass ( Achnatherum hymenoides) and bluebunch wheatgrass ( Pseudoroegneria spicata), and the non-native cereal rye ( Secale cereale), each in separate trays. Kangaroo rats preferentially harvested Indian ricegrass while pocket mice predominately harvested Indian ricegrass and cereal rye. Pocket mice were more likely to scatter hoard preferred seeds, whereas kangaroo rats mostly consumed and/or larder hoarded preferred seeds. No predator cue significantly affected seed preferences. However, both species altered seed handling behavior in response to direct predation cues by leaving more seeds available in the seed pool, though they responded to different predator cues. If these results translate to natural dynamics on the landscape, the two rodents are expected to have different impacts on seed survival and plant recruitment via their different seed selection and seed handling behaviors.

  16. Occurrence and distribution of Giardia species in wild rodents in Germany.

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    Helmy, Yosra A; Spierling, Nastasja G; Schmidt, Sabrina; Rosenfeld, Ulrike M; Reil, Daniela; Imholt, Christian; Jacob, Jens; Ulrich, Rainer G; Aebischer, Toni; Klotz, Christian

    2018-03-27

    Giardiasis is an important gastrointestinal parasitic disease in humans and other mammals caused by the protozoan Giardia duodenalis. This species complex is represented by genetically distinct groups (assemblages A-H) with varying zoonotic potential and host preferences. Wild rodents can harbor potentially zoonotic assemblages A and B, and the rodent-specific assemblage G. Other Giardia spp. found in these animals are Giardia muris and Giardia microti. For the latter, only limited information on genetic typing is available. It has been speculated that wild rodents might represent an important reservoir for parasites causing human giardiasis. The aim of this study was to investigate the occurrence and distribution of Giardia spp. and assemblage types in wild rodents from different study sites in Germany. Screening of 577 wild rodents of the genera Apodemus, Microtus and Myodes, sampled at eleven study sites in Germany, revealed a high overall Giardia prevalence. Giardia species determination at the SSU rDNA gene locus revealed that Apodemus mice, depending on species, were predominantly infected with one of two distinct G. muris sequence types. Giardia microti was the predominant parasite species found in voles of the genera Microtus and Myodes. Only a few animals were positive for potentially zoonotic G. duodenalis. Subtyping at the beta-giardin (bg) and glutamine dehydrogenase (gdh) genes strongly supported the existence of different phylogenetic subgroups of G. microti that are preferentially harbored by distinct host species. The present study highlights the preference of G. muris for Apodemus, and G. microti for Microtus and Myodes hosts and argues for a very low prevalence of zoonotic G. duodenalis assemblages in wild rodents in Germany. It also provides evidence that G. muris and G. microti subdivide into several phylogenetically distinguishable subgroups, each of which appears to be preferentially harbored by species of a particular rodent host genus

  17. Intestinal Helminths in Different Species of Rodents in North Khorasan Province, Northeast of Iran

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    Kourosh ARZAMANI

    2017-06-01

    Full Text Available Background: Rodents are an important source of zoonotic diseases for human. The aim of this study was to determine the infectivity of rodents with intestinal helminths in North Khorasan Province, Iran.Methods: One hundred and thirteen rodents were collected using different collection methods such as kill and live traps, digging of their burrow, filling of their hiding places with water and hand net during 2011-2013. Their alimentary canals were removed in the laboratory and helminths were determined in the department of parasitology, Tehran University of Medical Sciences.Results: Thirteen species of helminths parasites were found in 13 species of rodents, including Aspiculuris tetraptera, Hymenolepis diminuta, Nippostrongylus brasiliensis, Protospirura Seurat, Rictolaria ratti, Skrjabinitaenia lobata, Streptopharagus kuntzi, Syphacia obvelata, Taenia taeniaeformis, Trichuris muris, Cysticercus fasciolaris, Acanthocephal. spp and Trichuris spp. Some of them were reported for the first time in new host in Iran. S. obvelata and A. tetraptera were the most frequent parasites and P. Seurat, R. ratti and C. fasciolaris were found only in one rodent.Conclusion: This is the first study to investigate the intestinal parasites in rodents in this area. Among different species identified, some of helminths were reported in new host.

  18. Intestinal Helminths in Different Species of Rodents in North Khorasan Province, Northeast of Iran.

    Science.gov (United States)

    Arzamani, Kourosh; Salehi, Mitra; Mobedi, Iraj; Adinezade, Amir; Hasanpour, Hamid; Alavinia, Mohammad; Darvish, Jamshid; Shirzadi, Mohammad Reza; Mohammadi, Zeinolabedin

    2017-01-01

    Rodents are an important source of zoonotic diseases for human. The aim of this study was to determine the infectivity of rodents with intestinal helminths in North Khorasan Province, Iran. One hundred and thirteen rodents were collected using different collection methods such as kill and live traps, digging of their burrow, filling of their hiding places with water and hand net during 2011-2013. Their alimentary canals were removed in the laboratory and helminths were determined in the department of parasitology, Tehran University of Medical Sciences. Thirteen species of helminths parasites were found in 13 species of rodents, including Aspiculuris tetraptera, Hymenolepis diminuta, Nippostrongylus brasiliensis, Protospirura Seurat, Rictolaria ratti, Skrjabinitaenia lobata, Streptopharagus kuntzi, Syphacia obvelata, Taenia taeniaeformis, Trichuris muris, Cysticercus fasciolaris, Acanthocephal. spp and Trichuris spp . Some of them were reported for the first time in new host in Iran. S. obvelata and A. tetraptera were the most frequent parasites and P. Seurat, R. ratti and C. fasciolaris were found only in one rodent. This is the first study to investigate the intestinal parasites in rodents in this area. Among different species identified, some of helminths were reported in new host.

  19. Subcellular binding of 239Pu in the liver of selected species of rodents

    International Nuclear Information System (INIS)

    Winter, R.

    1980-01-01

    The subcellular distribution of 239 Pu in the liver of selected rodent species was investigated as well as the relation between 239 Pu and the iron metabolism. The goal of the investigation was to find out why the liver discharge of 239 Pu from the liver varies so much between species. (orig.) [de

  20. Genetic identification of Iberian rodent species using both mitochondrial and nuclear loci: application to noninvasive sampling.

    Science.gov (United States)

    Barbosa, S; Pauperio, J; Searle, J B; Alves, P C

    2013-01-01

    Species identification through noninvasive sampling is increasingly used in animal conservation genetics, given that it obviates the need to handle free-living individuals. Noninvasive sampling is particularly valuable for elusive and small species such as rodents. Although rodents are not usually assumed to be the most obvious target for conservation, of the 21 species or near-species present in Iberia, three are considered endangered and declining, while several others are poorly studied. Here, we develop a genetic tool for identifying all rodent species in Iberia by noninvasive genetic sampling. To achieve this purpose, we selected one mitochondrial gene [cytochrome b (cyt-b)] and one nuclear gene [interphotoreceptor retinoid-binding protein (IRBP)], which we first sequenced using tissue samples. Both genes allow for the phylogenetic distinction of all species except the sibling species Microtus lusitanicus and Microtus duodecimcostatus. Overall, cyt-b showed higher resolution than IRBP, revealing a clear barcoding gap. To allow these markers to be applied to noninvasive samples, we selected a short highly diagnostic fragment from each gene, which we used to obtain sequences from faeces and bones from owl pellets. Amplification success for the cyt-b and IRBP fragment was 85% and 43% in faecal and 88% and 64% in owl-pellet DNA extractions, respectively. The method allows the unambiguous identification of the great majority of Iberian rodent species from noninvasive samples, with application in studies of distribution, spatial ecology and population dynamics, and for conservation. © 2012 Blackwell Publishing Ltd.

  1. Prevalence of Leishmania species in rodents: A systematic review and meta-analysis in Iran.

    Science.gov (United States)

    Foroutan, Masoud; Khademvatan, Shahram; Majidiani, Hamidreza; Khalkhali, Hamidreza; Hedayati-Rad, Faezeh; Khashaveh, Shahla; Mohammadzadeh, Habib

    2017-08-01

    Leishmaniasis are diverse group of diseases caused by numerous species of genus Leishmania. Herein we have contrived a systematic review and meta-analysis on the prevalence of Leishmania species in rodents of Iran. For this purpose, following the general methodology recommended for systematic reviews and meta-analysis, six English databases (PubMed, Science Direct, Scopus, Ovid, Web of Science and Google Scholar) and four Persian databases (Magiran, SID, Iran Doc and Iran Medex) were explored during January 1995 till June 2015. Papers were selected based on 8 pre-defined inclusion criteria. During the years, a total number of 4485 different rodents were captured; among which 1291 cases were Leishmania positive. The calculated weighted prevalence of Leishmania species in rodents was 23% (95% CI=18-28). Given geographical zones of Iran, the highest and lowest prevalence rate was belonged to North 50% (95% CI=40-61) and West 11% (95% CI=5-17), respectively. Rhombomys opimus (1766), Meriones lybicus (1258) and Tatera indica (488) were the three most abundant captured rodents, while the highest prevalence of Leishmania species was observed in Nesokia indica 48% (95% CI=42-54) and followed by R. opimus 39% (95% CI=30-47). Egger's regression test was performed to detect publication bias, which revealed it may not have a significant influence on overall weighted prevalence estimate (P=0.317). Meta-regression analysis demonstrated that there is no significant relationship between overall prevalence with sample size (P=0.1) and year of publication (P=0.7). The results showed remarkable prevalence of Leishmania species in rodent reservoirs. In future, adopting a suitable strategy for control and combat with rodents is necessary. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Brain development in rodents and humans: Identifying benchmarks of maturation and vulnerability to injury across species

    Science.gov (United States)

    Semple, Bridgette D.; Blomgren, Klas; Gimlin, Kayleen; Ferriero, Donna M.; Noble-Haeusslein, Linda J.

    2013-01-01

    Hypoxic-ischemic and traumatic brain injuries are leading causes of long-term mortality and disability in infants and children. Although several preclinical models using rodents of different ages have been developed, species differences in the timing of key brain maturation events can render comparisons of vulnerability and regenerative capacities difficult to interpret. Traditional models of developmental brain injury have utilized rodents at postnatal day 7–10 as being roughly equivalent to a term human infant, based historically on the measurement of post-mortem brain weights during the 1970s. Here we will examine fundamental brain development processes that occur in both rodents and humans, to delineate a comparable time course of postnatal brain development across species. We consider the timing of neurogenesis, synaptogenesis, gliogenesis, oligodendrocyte maturation and age-dependent behaviors that coincide with developmentally regulated molecular and biochemical changes. In general, while the time scale is considerably different, the sequence of key events in brain maturation is largely consistent between humans and rodents. Further, there are distinct parallels in regional vulnerability as well as functional consequences in response to brain injuries. With a focus on developmental hypoxicischemic encephalopathy and traumatic brain injury, this review offers guidelines for researchers when considering the most appropriate rodent age for the developmental stage or process of interest to approximate human brain development. PMID:23583307

  3. Comparison of food hoarding of two sympatric rodent species under interspecific competition.

    Science.gov (United States)

    Zhang, Yi-Feng; Tong, Lei; Ji, Wei-Hong; Lu, Ji-Qi

    2013-01-01

    Competition can greatly affect the food hoarding strategies of rodents and the fate of seeds hoarded. In order to understand the influence of interspecific competition on food caching behavior of sympatric rodents, we investigated food hoarding patterns of two sympatric rodent species, buff-breasted rat (Rattus flavipectus) and Chinese white-bellied rat (Niviventor confucianus), and compared their responses and adjustment in hoarding behavior under interspecific competition. The results showed that: (1) the buff-breasted rat larder hoarded seeds only, while Chinese white-bellied rat hoarded seeds in both larder and scatter forms; (2) two species of rodents both larder hoarded more seeds when competitors were present; and (3) the Chinese white-bellied rats adjusted their seed hoarding from scatter to larder when competitors were introduced, which reduced the seed availability. Therefore, we concluded that rodents would adjust their food hoarding strategy when interspecific competitors were present, and this may produce a different effect on the fate of seeds and the recruitment of plants. This article is part of a Special Issue entitled: insert SI title. Copyright © 2012. Published by Elsevier B.V.

  4. Wheat or barley? Feeding preferences affect distribution of three rodent species in agricultural landscape

    Czech Academy of Sciences Publication Activity Database

    Heroldová, Marta; Tkadlec, E.; Bryja, Josef; Zejda, J.

    2008-01-01

    Roč. 110, 3-4 (2008), s. 354-362 ISSN 0168-1591 R&D Projects: GA ČR GA206/04/2003 Institutional research plan: CEZ:AV0Z60930519 Keywords : agro-ecosystem * small rodent species * diet preference * habitat preference Subject RIV: EH - Ecology, Behaviour Impact factor: 1.823, year: 2008

  5. Long-lived cancer-resistant rodents as new model species for cancer research

    Directory of Open Access Journals (Sweden)

    Jorge eAzpurua

    2013-01-01

    Full Text Available Most rodents are small and short-lived, but several lineages have independently evolved long lifespans without a concomitant increase in body mass. Most notably, the two subterranean species naked mole rat (NMR and blind mole rat (BMR which have maximum lifespans of 32 and 21 years respectively. The longevity of these species has sparked interest in the tumor suppression strategies that may have also evolved, because for many rodent species (including mice, rats, guinea pigs, gerbils and hamsters tumors are major source of late-life mortality. Here, we review the recent literature on anticancer mechanisms in long-lived rodents. Both NMR and BMR seem to have developed tumor defenses that rely on extra-cellular signals. However, while the NMR relies on a form of contact inhibition to suppress growth, the BMR evolved a mechanism mediated by the release of interferon and rapid necrotic cell death. Although both organisms ultimately rely on canonical downstream tumor suppressors (pRB and p53 the studies reveal species can evolve different strategies to achieve tumor-resistance. Importantly, studies of these cancer-resistant rodents may benefit human health if such mechanisms can be activated in human cells.

  6. 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....... METHODS: We examined the reproductive tract of nonpregnant (n = 5), early (n = 3) and mid to late gestation (n = 2) females. Selected characters were mapped to a phylogenetic tree to examine their evolution in rodents. RESULTS: The chorionic placenta was discoid and labyrinthine with a spongy zone...

  7. Prevalence of zoonotic Bartonella species among rodents and shrews in Thailand.

    Science.gov (United States)

    Pangjai, Decha; Maruyama, Soichi; Boonmar, Sumalee; Kabeya, Hidenori; Sato, Shingo; Nimsuphan, Burin; Petkanchanapong, Wimol; Wootta, Wattanapong; Wangroongsarb, Piyada; Boonyareth, Maskiet; Preedakoon, Poom; Saisongkorh, Watcharee; Sawanpanyalert, Pathom

    2014-03-01

    We investigated the prevalence of Bartonella species in 10 rodent and one shrew species in Thailand. From February 2008 to May 2010, a total of 375 small animals were captured in 9 provinces in Thailand. Bartonella strains were isolated from 57 rodents (54 from Rattus species and 3 from Bandicota indica) and one shrew (Suncus murinus) in 7 of the 9 provinces, and identified to the species level. Sequence analysis of the citrate synthase and RNA polymerase β subunit genes identified the 58 isolates from each Bartonella-positive animal as B. tribocorum in 27 (46.6%) animals, B. rattimassiliensis in 17 (29.3%) animals, B. elizabethae in 10 (17.2%) animals and B. queenslandensis in 4 (6.9%) animals. R. norvegicus, R. rattus, and Suncus murinus carried B. elizabethae, which causes endocarditis in humans. The prevalence of Bartonella bacteremic animals by province was 42.9% of the animals collected in Phang Nga, 26.8% in Chiang Rai, 20.4% in Sa Kaeo, 16.7% in Nakhon Si Thammarat, 12.0% in Surat Thani, 9.1% in Mae Hong Son and Loei Provinces. These results indicate that Bartonella organisms are widely distributed in small mammals in Thailand and some animal species may serve as important reservoirs of zoonotic Bartonella species in the country. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  8. Tritium water as a marker for the measurement of body water turnover rates in desert livestock, rodent and bird species

    International Nuclear Information System (INIS)

    Khan, M.S.; Ghosh, P.K.; Bohra, R.C.

    1990-01-01

    Tritiated water has been used for estimating body water turnover rates (BWTRs) in desert livestock, rodent and birds. BWTRs in relation to adaption of these animal species to desert environment have been discussed. (author). 5 refs., 2 tabs

  9. Molecular Survey on Brucellosis in Rodents and Shrews - Natural Reservoirs of Novel Brucella Species in Germany?

    Science.gov (United States)

    Hammerl, J A; Ulrich, R G; Imholt, C; Scholz, H C; Jacob, J; Kratzmann, N; Nöckler, K; Al Dahouk, S

    2017-04-01

    Brucellosis is a widespread zoonotic disease introduced from animal reservoirs to humans. In Germany, bovine and ovine/caprine brucellosis were eradicated more than a decade ago and mandatory measures in livestock have been implemented to keep the officially brucellosis-free status. In contrast, surveillance of wildlife is still challenging, and reliable data on the prevalence of brucellae in small mammal populations do not exist. To assess the epidemiology of Brucella spp. in rodents and shrews, a molecular survey was carried out. A total of 537 rodents and shrews were trapped in four federal states located throughout Germany and investigated for the presence of Brucella. Using a two-step molecular assay based on the detection of the Brucella-specific bcsp31 and IS711 sequences in tissue samples, 14.2% (n = 76) of the tested animals were positive. These originated mainly from western and south-western Germany, where preliminary analyses indicate population density-dependent Brucella prevalence in voles (Myodes glareolus) and mice (Apodemus spp.). recA typing revealed a close relationship to a potentially novel Brucella species recently isolated from red foxes (Vulpes vulpes) in Austria. The molecular detection of brucellae in various rodent taxa and for the first time in shrew species shows that these animals may be naturally infected or at least have a history of exposure to Brucella spp. © 2015 Blackwell Verlag GmbH.

  10. 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.

  11. New occurrences and biological aspects to four species of rodents (Mammalia: Cricetidae from Brazil

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    Felipe Santana Machado

    2015-07-01

    Full Text Available The most representative group among mammals are rodents for presenting high ratio to the total of species. However, rodents are considered a "taxonomic chaos" and some species such as Blarinomys breviceps, Bibimys labiosus, Akodon lindberghi and Pseudoryzomys simplex are little known. That can be explained because of low occurrence of small terrestrial mammals in wildlife inventories and/or reduced abundance. The objective is to describe the occurrence of these species and analyze these locations presenting descriptive comments about their biological aspects. Therefore, in addition to specimens collected in the field, some scientific collections were visited and reviews in relevant literature were conducted in order to obtain information about the locations and biological aspects. Akodon lindberghi was found in five sites, Bibimys labiosus was found in 15, Blarinomys breviceps in 39 and Pseudoryzomys simplex  in 13. Each species has specific information and they are included in two threatened areas, Atlantic Forest and Cerrado. The occurrences are disconnected and related to taxonomic and methodological problems. Keywords: New records. Rodentia. Sigmodontinae. Occurence area.

  12. Differences in Diet between Two Rodent Species, Mastomys natalensis and Gerbilliscus vicinus, in Fallow Land Habitats in Central Tanzania

    DEFF Research Database (Denmark)

    Mulungu, Loth S.; Massawe, Apia W.; Kennis, Jan

    2011-01-01

    simply reflect availability of food, and when food is limited, different animal species compete. In this study, the diet of two rodent pest species, Mastomys natalensis and Gerbilliscus vicinus, coexisting in fallow land in central Tanzania were studied to assess the degree of diet differentiation among......Differences in the ecological niche requirements among rodent species competing in the same habitat may result from differences in the use of one to three resources: space, time and food or some combination of these. Alternatively, differences in resource use utilization among animal species may...... them. Dietary niche breadth of G. vicinus was greater than that of M. natalensis in all stages of the maize cropping seasons. The rodent species studied overlapped considerably in the food items consumed ranging from niche overlap (Ojk) of 0.77–0.89. Grains/seeds featured high in the diet of M...

  13. Identification of Alpha and Beta Coronavirus in Wildlife Species in France: Bats, Rodents, Rabbits, and Hedgehogs

    Directory of Open Access Journals (Sweden)

    Elodie Monchatre-Leroy

    2017-11-01

    Full Text Available Coronaviruses are closely monitored in the context of emerging diseases and, as illustrated with Severe Acute Respiratory Syndrome coronavirus (SARS-CoV and Middle East Respiratory Syndrome-coronavirus (MERS-CoV, are known to cross the species barrier and eventually to move from wildlife to humans. Knowledge of the diversity of coronaviruses in wildlife is therefore essential to better understand and prevent emergence events. This study explored the presence of coronaviruses in four wild mammal orders in France: Bats, rodents, lagomorphs, and hedgehogs. Betacoronavirus and Alphacoronavirus genera were identified. The results obtained suggest the circulation of potentially evolving virus strains, with the potential to cross the species barrier.

  14. Identification of the facultative heterochromatic X chromosome in females of 25 rodent species.

    Science.gov (United States)

    Kanda, N; Yosida, T H

    1979-01-01

    Treatment of the chromosomes of 25 rodent species with a 50 degrees C hypotonic solution and Giemsa staining permitted identification of the heterochromatic X chromosome in 24 species. With this technique, the facultative of the heterochromatic X chromosome or the facultative portion of large, composite-type X chromosoms is stained darker than the other chromosomes, allowing it to be distinguished from the homologous euchromatic X chromosome in female metaphase cells. Intense staining of the single X chromosome was not observed in male metaphase cells. It is suggested that this differential staining of one of the two X chromosomes might be due to qualitative differences in chromosomal proteins rather than to differences in the degree of chromosomal condensation or in DNA base sequence.

  15. Dental microwear of sympatric rodent species sampled across habitats in southern Africa: Implications for environmental influence.

    Science.gov (United States)

    Burgman, Jenny H E; Leichliter, Jennifer; Avenant, Nico L; Ungar, Peter S

    2016-03-01

    Dental microwear textures have proven to be a valuable tool for reconstructing the diets of a wide assortment of fossil vertebrates. Nevertheless, some studies have recently questioned the efficacy of this approach, suggesting that aspects of habitat unrelated to food preference, especially environmental grit load, might have a confounding effect on microwear patterning that obscures the diet signal. Here we evaluate this hypothesis by examining microwear textures of 3 extant sympatric rodent species that vary in diet breadth and are found in a variety of habitat types: Mastomys coucha, Micaelamys namaquensis and Rhabdomys pumilio. We sample each of these species from 3 distinct environmental settings in southern Africa that differ in rainfall and vegetative cover: Nama-Karoo shrublands (semi-desert) and Dry Highveld grasslands in the Free State Province of South Africa, and Afromontane (wet) grasslands in the highlands of Lesotho. While differences between habitat types are evident for some of the species, inconsistency in the pattern suggests that the microwear signal is driven by variation in foods eaten rather than grit-level per se. It is clear that, at least for species and habitats sampled in the current study, environmental grit load does not swamp diet-related microwear signatures. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  16. Effects of Strain and Species on the Septo-Temporal Distribution of Adult Neurogenesis in Rodents

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    Franziska Wiget

    2017-12-01

    Full Text Available The functional septo-temporal (dorso-ventral differentiation of the hippocampus is accompanied by gradients of adult hippocampal neurogenesis (AHN in laboratory rodents. An extensive septal AHN in laboratory mice suggests an emphasis on a relation of AHN to tasks that also depend on the septal hippocampus. Domestication experiments indicate that AHN dynamics along the longitudinal axis are subject to selective pressure, questioning if the septal emphasis of AHN in laboratory mice is a rule applying to rodents in general. In this study, we used C57BL/6 and DBA2/Crl mice, wild-derived F1 house mice and wild-captured wood mice and bank voles to look for evidence of strain and species specific septo-temporal differences in AHN. We confirmed the septal > temporal gradient in C57BL/6 mice, but in the wild species, AHN was low septally and high temporally. Emphasis on the temporal hippocampus was particularly strong for doublecortin positive (DCX+ young neurons and more pronounced in bank voles than in wood mice. The temporal shift was stronger in female wood mice than in males, while we did not see sex differences in bank voles. AHN was overall low in DBA and F1 house mice, but they exhibited the same inversed gradient as wood mice and bank voles. DCX+ young neurons were usually confined to the subgranular zone and deep granule cell layer. This pattern was seen in all animals in the septal and intermediate dentate gyrus. In bank voles and wood mice however, the majority of temporal DCX+ cells were radially dispersed throughout the granule cell layer. Some but not all of the septo-temporal differences were accompanied by changes in the DCX+/Ki67+ cell ratios, suggesting that new neuron numbers can be regulated by both proliferation or the time course of maturation and survival of young neurons. Some of the septo-temporal differences we observe have also been found in laboratory rodents after the experimental manipulation of the molecular mechanisms

  17. Molecular detection of Leishmania infantum and Leishmania tropica in rodent species from endemic cutaneous leishmaniasis areas in Morocco.

    Science.gov (United States)

    Echchakery, Mohamed; Chicharro, Carmen; Boussaa, Samia; Nieto, Javier; Carrillo, Eugenia; Sheila, Ortega; Moreno, Javier; Boumezzough, Ali

    2017-10-02

    Leishmaniasis remains a major public health problem in African nations, including Morocco, where little is known about the vertebrate reservoirs involved in the causal parasites' transmission cycles. The present study investigates the role of rodent species as potential reservoirs of Leishmania spp. in central Morocco, where both L. tropica and L. infantum have been reported. Rodents were caught from 22 sites in central Morocco, by using Sherman metal traps, and identified morphologically. For each specimen, genomic DNA was extracted from different tissues using the Speed Tools DNA extraction Kit. Then, samples were PCR-analyzed, targeting the SSU rRNA gene to detect Leishmania spp. DNA, followed by amplification of the internal transcribed spacer 1 (ITS1) and its sequencing to identify the species. A total of 197 rodents belonging to ten species were captured and identified: Rattus rattus (40.61%), Mus musculus (25.38%), Apodemus sylvaticus (8.63%), Mus spretus (7.11%), Meriones shawi (5.58%), Rattus norvegicus (4.57%), Meriones libycus (3.05%), Mastomys erythroleucus (2.03%), Gerbillus campestris (2.03%) and Lemniscomys barbarus (1.01%). Molecular analysis revealed the presence of Leishmania species in 18 specimens: six R. rattus (out of 80 captured; 7.5%), 11 M. musculus (out of 50 captured; 22%), and one R. norvegicus (out of 9 captured; 11.11%). To the best of our knowledge, L. infantum and L. tropica were identified in rodent species for the first time in Morocco. These findings suggest that rodent species may be involved in L. infantum and L. tropica transmission cycles in this country but that further studies are needed to confirm their role as reservoirs of Leishmania species in Morocco.

  18. Imaging mass spectrometry identifies prognostic ganglioside species in rodent intracranial transplants of glioma and medulloblastoma.

    Directory of Open Access Journals (Sweden)

    Leonardo Ermini

    Full Text Available Matrix-assisted laser desorption ionization (MALDI imaging mass spectrometry (MALDI-MSI allows us to investigate the distribution of lipid molecules within tissues. We used MALDI-MSI to identify prognostic gangliosides in tissue sections of rat intracranial allografts of rat glioma and mouse intracranial xenografts of human medulloblastoma. In the healthy adult rodent brain, GM1 and GD1 were the main types of glycolipids. Both gangliosides were absent in both intracranial transplants. The ganglioside GM3 was not present in the healthy adult brain but was highly expressed in rat glioma allografts. In combination with tandem mass spectrometry GM3 (d18:1/C24:0 was identified as the most abundant ganglioside species in the glioma allotransplant. By contrast, mouse xenografts of human medulloblastoma were characterized by prominent expression of the ganglioside GM2 (d18:0/C18:0. Together, these data demonstrate that tissue-based MALDI-MSI of gangliosides is able to discriminate between different brain tumors and may be a useful clinical tool for their classification and grading.

  19. Plague cycles in two rodent species from China: Dry years might provide context for epizootics in wet years

    Science.gov (United States)

    Eads, David A.; Biggins, Dean E.; Xu, Lei; Liu, Qiyong

    2016-01-01

    Plague, a rodent-associated, flea-borne zoonosis, is one of the most notorious diseases in history. Rates of plague transmission can increase when fleas are abundant. Fleas commonly desiccate and die when reared under dry conditions in laboratories, suggesting fleas will be suppressed during droughts in the wild, thus reducing the rate at which plague spreads among hosts. In contrast, fleas might increase in abundance when precipitation is plentiful, producing epizootic outbreaks during wet years. We tested these hypotheses using a 27-yr data set from two rodents in Inner Mongolia, China: Mongolian gerbils (Meriones unguiculatus) and Daurian ground squirrels (Spermophilus dauricus). For both species of rodents, fleas were most abundant during years preceded by dry growing seasons. For gerbils, the prevalence of plague increased during wet years preceded by dry growing seasons. If precipitation is scarce during the primary growing season, succulent plants decline in abundance and, consequently, herbivorous rodents can suffer declines in body condition. Fleas produce more offspring and better survive when parasitizing food-limited hosts, because starving animals tend to exhibit inefficient behavioral and immunological defenses against fleas. Further, rodent burrows might buffer fleas from xeric conditions aboveground during dry years. After a dry year, fleas might be abundant due to the preceding drought, and if precipitation and succulent plants become more plentiful, rodents could increase in density, thereby creating connectivity that facilitates the spread of plague. Moreover, in wet years, mild temperatures might increase the efficiency at which fleas transmit the plague bacterium, while also helping fleas to survive as they quest among hosts. In this way, dry years could provide context for epizootics of plague in wet years.

  20. Murid herpesvirus-4 exploits dendritic cells to infect B cells.

    Directory of Open Access Journals (Sweden)

    Miguel Gaspar

    2011-11-01

    Full Text Available Dendritic cells (DCs play a central role in initiating immune responses. Some persistent viruses infect DCs and can disrupt their functions in vitro. However, these viruses remain strongly immunogenic in vivo. Thus what role DC infection plays in the pathogenesis of persistent infections is unclear. Here we show that a persistent, B cell-tropic gamma-herpesvirus, Murid Herpesvirus-4 (MuHV-4, infects DCs early after host entry, before it establishes a substantial infection of B cells. DC-specific virus marking by cre-lox recombination revealed that a significant fraction of the virus latent in B cells had passed through a DC, and a virus attenuated for replication in DCs was impaired in B cell colonization. In vitro MuHV-4 dramatically altered the DC cytoskeleton, suggesting that it manipulates DC migration and shape in order to spread. MuHV-4 therefore uses DCs to colonize B cells.

  1. Experimental infection of nontarget species of rodents and birds with Brucella abortus strain RB51 vaccine

    Science.gov (United States)

    Januszewski, M.C.; Olsen, S.C.; McLean, R.G.; Clark, L.; Rhyan, Jack C.

    2001-01-01

    The Brucella abortus vaccine strain RB51 (SRB51) is being considered for use in the management of bnucellosis in wild bison (Bison bison) and elk (Cervus elaphus) populations in the Greater Yellowstone Area (USA). Evaluation of the vaccines safety in non-target species was considered necessary prior to field use. Between June 1998 and December 1999, ground squirrels (Spermophilus richardsonii, n = 21), deer mice (Peromyscus maniculatus, n = 14), prairie voles (Microtus ochrogaster, n = 21), and ravens (Corvus corax, n = 13) were orally inoculated with SRB51 or physiologic saline. Oral and rectal swabs and blood samples were collected for bacteriologic evaluation. Rodents were necropsied at 8 to 10 wk and 12 to 21 wk post inoculation (PI), and ravens at 7 and 11 wk PI. Spleen, liver and reproductive tissues were collected for bacteriologic and histopathologic evaluation. No differences in clinical signs, appetite, weight loss or gain, or activity were observed between saline- and SRB51-inoculated animals in all four species. Oral and rectal swabs from all species were negative throughout the study. In tissues obtained from SRB51-inoculated animals, the organism was isolated from six of seven (86%) ground squirrels, one of six (17%) deer mice, none of seven voles, and one of five (20%) ravens necropsied at 8, 8, 10, and 7 wk PI, respectively. Tissues from four of seven (57%) SRB51-inoculated ground squirrels were culture positive for the organism 12 wk PI; SRB51 was not recovered from deer mice, voles. or ravens necropsied 12, 21, or 11 wk, respectively, PI. SRB51 was not recovered from saline-inoculated ground squirrels, deer mice, or voles at any time but was recovered from one saline-inoculated raven at necropsy, 7 wk PI, likely attributable to contact with SRB51-inoculated ravens in an adjacent aviary room. Spleen was time primary tissue site of colonization in ground squirrels, followed by the liver and reproductive organs. The results indicate oral exposure to

  2. A new species of the Rodent Baiomys from Aruba and Curaçao

    NARCIS (Netherlands)

    Husson, A.M.

    1960-01-01

    In his paper on the mammals of the islands of Aruba, Curaçao, and Bonaire (situated off the north coast of Venezuela), WAGENAAR HUMMELINCK (1940 a, p. 69) mentioned a juvenile specimen of a cricetine rodent which was identified by Mr. M. A. C. HINTON and Mr. R. W. HAYMAN as probably belonging to the

  3. Proteomic characterization of murid herpesvirus 4 extracellular virions.

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    Sarah Vidick

    Full Text Available Gammaherpesvirinae, such as the human Epstein-Barr virus (EBV and the Kaposi's sarcoma associated herpesvirus (KSHV are highly prevalent pathogens that have been associated with several neoplastic diseases. As EBV and KSHV are host-range specific and replicate poorly in vitro, animal counterparts such as Murid herpesvirus-4 (MuHV-4 have been widely used as models. In this study, we used MuHV-4 in order to improve the knowledge about proteins that compose gammaherpesviruses virions. To this end, MuHV-4 extracellular virions were isolated and structural proteins were identified using liquid chromatography tandem mass spectrometry-based proteomic approaches. These analyses allowed the identification of 31 structural proteins encoded by the MuHV-4 genome which were classified as capsid (8, envelope (9, tegument (13 and unclassified (1 structural proteins. In addition, we estimated the relative abundance of the identified proteins in MuHV-4 virions by using exponentially modified protein abundance index analyses. In parallel, several host proteins were found in purified MuHV-4 virions including Annexin A2. Although Annexin A2 has previously been detected in different virions from various families, its role in the virion remains controversial. Interestingly, despite its relatively high abundance in virions, Annexin A2 was not essential for the growth of MuHV-4 in vitro. Altogether, these results extend previous work aimed at determining the composition of gammaherpesvirus virions and provide novel insights for understanding MuHV-4 biology.

  4. Hubungan antara Aktivitas Fisik Terhadap Memori Kerja Murid SMA Don Bosco III Bekasi

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    Michelle Clarissa Junaidi

    2017-03-01

    Full Text Available Latar belakang. Memori kerja merupakan bagian dari memori jangka pendek yang berperan penting dalam membantu proses pembelajaran dan dipengaruhi oleh aktivitas fisik, memori kerja yang rendah akan menimbulkan kesulitan untuk menerima informasi baru serta penurunan prestasi belajar. Tujuan. Mengetahui pengaruh aktivitas fisik terhadap kapasitas memori kerja murid SMA Don Bosco III. Metode. Penelitian metode analitik dengan pendekatan potong lintang pada 113 murid SMA Don Bosco III, Bekasi, pada 18 – 20 Juli 2016. Penelitian dilakukan dengan menggunakan kuesioner demografi, kuesioner skrining gangguan mental dan penyakit kronis, Physical Acitivity Questionnaire of Adolescent (PAQ-A dan Operation Span (O-SPAN. Analisis data dengan univariat dan bivariat menggunakan uji korelasi Spearman. Hasil. Terdapat 113 murid SMA Don Bosco III dengan kisaran usia 14 – 17 tahun, usia terbanyak 15 tahun (47.8%, laki-laki 61,1%, murid kelas X 44.2%. Mayoritas responden memiliki aktivitas fisik “kurang baik” dan rerata memori kerja 6,16. Analisis Spearman menunjukkan terdapat hubungan bermakna (p<0,05 antara aktivitas fisik terhadap memori kerja dengan korelasi positif lemah (r=0,384. Kesimpulan. Terdapat korelasi positif antara aktivitas fisik dan memori kerja, aktivitas fisik yang semakin tinggi cenderung akan meningkatkan memori kerja.

  5. KASUS KECACINGAN PADA MURID SEKOLAH DASAR DI KECAMATAN MENTEWE, KABUPATEN TANAH BUMBU KALIMANTAN SELATAN TAHUN 2010

    Directory of Open Access Journals (Sweden)

    Dina Bisara

    2016-07-01

    kesehatan masyarakat diIndonesia yang berhubungan erat dengan kondisi lingkungan. Prevalensi kecacingan di suatu daerah sangatbervariasi tergantung dari beberapa faktor antara lain kelembaban, kondisi tanah, higiene sanitasi,kelompok umur yang diperiksa. Usia sekolah dasar merupakan golongan yang sering terkena infeksikecacingan karena sering berhubungan dengan tanah yang tercemar telur cacing. Tujuan penelitian iniadalah untuk mengetahui kasus kecacingan pada anak sekolah dasar serta mengetahui Pengetahuan Sikapdan Perilaku (PSP masyarakat di sekitar pemukiman bekas penambangan batubara di Kecamatan Mentewe, Kabupaten Tanah Bumbu Kalimantan Selatan tahun 2010. Penelitian ini merupakan penelitiandeskriptif dengan rancangancrossectional.Pemeriksaan sampel tinja di lokasi penelitian dilakukan denganpemeriksaan secara langsung pada kaca benda dengan menggunakan cairan logol 2 %. Dari hasil penelitian didapatkan pada 106 anak sekolah dasar yang diperiksa, sebanyak 18 anak (17 % positif kecacingan,dengan parasite rate 7 anak (38,9 %Ascaris lumbricoides,2 anak (11,1%Trichuris trichiura,3 anak(16,7% cacing tambang, 5 anak mix (27,8 % yaitu ; 3 anak detemukan dengan dua jenis cacing Asc.lumbricoidesdan T. trichiuraserta 2 anak detemukan dengan dua species cacingAsc. lumbricoides dancacing tambang. Selain ketiga jenis cacing di atas juga ditemukan sate jenis cacing pada 1 anak yaitu Hvmenolepis nana.Pengetahuan respoden tentang kecacingan di Kecamatan Mentewe sebesar 98,5%menyatakan pernah mendengar tentang kecacingan. Daerah penelitian banyak anak-anak mereka yang masih usia sekolah dasar mengalami kecacingan tetapi tidak dianggap berbahaya oleh orang tua mereka.Kesimpulan dari penelitian ini, kecacingan pada murid SD yang ditemukan yaitu cacing Ascaris lumbricoides, T trichiuria, Hymenotepis nanodan cacing tambang . Pengetahuan, sikap dan perilaku masyarakat terhadap cars pengobatan, pencegahan kecacingan, menunjukkan bahwa masih sangat kurang.Kata kunci: Kecacingan, PSP

  6. Hubungan Asupan Zat Gizi dan Indeks Masa Tubuh dengan Hiperlipidemia pada Murid SLTP yang Obesitas di Yogyakarta

    OpenAIRE

    Siti Nurul Hidayati; Hamam Hadi; W. Lestariana

    2016-01-01

    Latar belakang. Obesitas pada anak dan remaja meningkatkan risiko penyakit degeneratif dan kardiovaskular. Namun belum jelas apakah remaja yang obesitas berisiko mengalami hiperlipidemia Tujuan. Menilai hubungan antara indeks masa tubuh (IMT), asupan karbohidrat dan lemak dengan hiperlipidemia pada murid SLTP yang obesitas. Metoda. Penelitian cross sectional di Yogyakarta. Sampel 109 murid SLTP dengan IMT = persentile-95 kurve IMT dari NCHS-CDC, dipilih secara acak dari muri...

  7. Circadian phase and period responses to light stimuli in two nocturnal rodents

    NARCIS (Netherlands)

    Sharma, Vijay Kumar; Daan, Serge

    2002-01-01

    We report period response curves (tauRC) for two nocturnal Murid species from India, Mus booduga and Mus platythrix. We further discuss the method of phase shift estimation in the presence of tau-changes, because such changes pose a serious methodological problem in the estimation of phase shifts.

  8. Native rodent species are unlikely sources of infection for Leishmania (Viannia braziliensis along the Transoceanic Highway in Madre de Dios, Peru.

    Directory of Open Access Journals (Sweden)

    Lisa A Shender

    Full Text Available An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V. braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%, Hylaeamys perenensis (15.7%, and Proechimys spp. (12%. All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V. braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V. braziliensis transmission to human inhabitants in this highly prevalent region.

  9. Native rodent species are unlikely sources of infection for Leishmania (Viannia) braziliensis along the Transoceanic Highway in Madre de Dios, Peru.

    Science.gov (United States)

    Shender, Lisa A; De Los Santos, Maxy; Montgomery, Joel M; Conrad, Patricia A; Ghersi, Bruno M; Razuri, Hugo; Lescano, Andres G; Mazet, Jonna A K

    2014-01-01

    An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V.) braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail) were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%), Hylaeamys perenensis (15.7%), and Proechimys spp. (12%). All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V.) braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V.) braziliensis transmission to human inhabitants in this highly prevalent region.

  10. Species-specific escape of Plasmodium sporozoites from oocysts of avian, rodent, and human malarial parasites.

    Science.gov (United States)

    Orfano, Alessandra S; Nacif-Pimenta, Rafael; Duarte, Ana P M; Villegas, Luis M; Rodrigues, Nilton B; Pinto, Luciana C; Campos, Keillen M M; Pinilla, Yudi T; Chaves, Bárbara; Barbosa Guerra, Maria G V; Monteiro, Wuelton M; Smith, Ryan C; Molina-Cruz, Alvaro; Lacerda, Marcus V G; Secundino, Nágila F C; Jacobs-Lorena, Marcelo; Barillas-Mury, Carolina; Pimenta, Paulo F P

    2016-08-02

    Malaria is transmitted when an infected mosquito delivers Plasmodium sporozoites into a vertebrate host. There are many species of Plasmodium and, in general, the infection is host-specific. For example, Plasmodium gallinaceum is an avian parasite, while Plasmodium berghei infects mice. These two parasites have been extensively used as experimental models of malaria transmission. Plasmodium falciparum and Plasmodium vivax are the most important agents of human malaria, a life-threatening disease of global importance. To complete their life cycle, Plasmodium parasites must traverse the mosquito midgut and form an oocyst that will divide continuously. Mature oocysts release thousands of sporozoites into the mosquito haemolymph that must reach the salivary gland to infect a new vertebrate host. The current understanding of the biology of oocyst formation and sporozoite release is mostly based on experimental infections with P. berghei, and the conclusions are generalized to other Plasmodium species that infect humans without further morphological analyses. Here, it is described the microanatomy of sporozoite escape from oocysts of four Plasmodium species: the two laboratory models, P. gallinaceum and P. berghei, and the two main species that cause malaria in humans, P. vivax and P. falciparum. It was found that sporozoites have species-specific mechanisms of escape from the oocyst. The two model species of Plasmodium had a common mechanism, in which the oocyst wall breaks down before sporozoites emerge. In contrast, P. vivax and P. falciparum sporozoites show a dynamic escape mechanism from the oocyst via polarized propulsion. This study demonstrated that Plasmodium species do not share a common mechanism of sporozoite escape, as previously thought, but show complex and species-specific mechanisms. In addition, the knowledge of this phenomenon in human Plasmodium can facilitate transmission-blocking studies and not those ones only based on the murine and avian models.

  11. First amplification of Eimeria hessei DNA from the lesser horseshoe bat (Rhinolophus hipposideros) and its phylogenetic relationships with Eimeria species from other bats and rodents.

    Science.gov (United States)

    Afonso, Eve; Baurand, Pierre-Emmanuel; Tournant, Pierline; Capelli, Nicolas

    2014-04-01

    Although coccidian parasites of the genus Eimeria are among the best-documented parasites in bats, few Eimeria species found in bats have been characterised using molecular tools, and none of the characterised species are found in European countries. Phylogenetic relationships of Eimeria species that parasitise bats and rodents can be related to the morphology of oocysts, independently from host range, suggesting that these species are derived from common ancestors. In the present study, we isolated a partial sequence of the Eimeria hessei 18S rRNA gene from the lesser horseshoe bat (Rhinolophus hipposideros), a European bat species. Droppings from lesser horseshoe bats were collected from 11 maternity roosts located in France that were positive for the presence of the parasite. Through morphological characterisation, the oocysts detected in the lesser horseshoe bat droppings were confirmed to be E. hessei. The unique E. hessei sequence obtained through molecular analysis belonged to a clade that includes both rodent and bat Eimeria species. However, the E. hessei oocysts isolated from the bat droppings did not show morphological similarities to rodent Eimeria species. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Negligible senescence in the longest living rodent, the naked mole-rat: insights from a successfully aging species.

    Science.gov (United States)

    Buffenstein, Rochelle

    2008-05-01

    Aging refers to a gradual deterioration in function that, over time, leads to increased mortality risk, and declining fertility. This pervasive process occurs in almost all organisms, although some long-lived trees and cold water inhabitants reportedly show insignificant aging. Negligible senescence is characterized by attenuated age-related change in reproductive and physiological functions, as well as no observable age-related gradual increase in mortality rate. It was questioned whether the longest living rodent, the naked mole-rat, met these three strict criteria. Naked mole-rats live in captivity for more than 28.3 years, approximately 9 times longer than similar-sized mice. They maintain body composition from 2 to 24 years, and show only slight age-related changes in all physiological and morphological characteristics studied to date. Surprisingly breeding females show no decline in fertility even when well into their third decade of life. Moreover, these animals have never been observed to develop any spontaneous neoplasm. As such they do not show the typical age-associated acceleration in mortality risk that characterizes every other known mammalian species and may therefore be the first reported mammal showing negligible senescence over the majority of their long lifespan. Clearly physiological and biochemical processes in this species have evolved to dramatically extend healthy lifespan. The challenge that lies ahead is to understand what these mechanisms are.

  13. Gender and Species Differences in Triadimefon Metabolism by Rodent Hepatic Microsomes

    Science.gov (United States)

    Understanding the potential differences in metabolic capacity and kinetics between various common laboratory species as well as between genders is an important facet of chemical risk assessment that is often overlooked, particularly for chemicals which undergo non-cytochrome P450...

  14. The role of early life experience and species differences in alcohol intake in microtine rodents.

    Directory of Open Access Journals (Sweden)

    Allison M J Anacker

    Full Text Available Social relationships have important effects on alcohol drinking. There are conflicting reports, however, about whether early-life family structure plays an important role in moderating alcohol use in humans. We have previously modeled social facilitation of alcohol drinking in peers in socially monogamous prairie voles. We have also modeled the effects of family structure on the development of adult social and emotional behaviors. Here we assessed whether alcohol intake would differ in prairie voles reared by both parents compared to those reared by a single mother. We also assessed whether meadow voles, a closely related species that do not form lasting reproductive partnerships, would differ in alcohol drinking or in the effect of social influence on drinking. Prairie voles were reared either bi-parentally (BP or by a single mother (SM. BP- and SM-reared adult prairie voles and BP-reared adult meadow voles were given limited access to a choice between alcohol (10% and water over four days and assessed for drinking behavior in social and non-social drinking environments. While alcohol preference was not different between species, meadow voles drank significantly lower doses than prairie voles. Meadow voles also had significantly higher blood ethanol concentrations than prairie voles after receiving the same dose, suggesting differences in ethanol metabolism. Both species, regardless of rearing condition, consumed more alcohol in the social drinking condition than the non-social condition. Early life family structure did not significantly affect any measure. Greater drinking in the social condition indicates that alcohol intake is influenced similarly in both species by the presence of a peer. While the ability of prairie voles to model humans may be limited, the lack of differences in alcohol drinking in BP- and SM-reared prairie voles lends biological support to human studies demonstrating no effect of single-parenting on alcohol abuse.

  15. The role of natural radioresistance and ecological specialization of a specie in radio adaptation (as exemplified by natural rodent populations)

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    Grigorkina, E.; Olenev, G. [Institute of Plant and Animal Ecology, Ural Branch RAS, Ekaterinburg, (Russian Federation)

    2004-07-01

    The problem of mammal radio-adaptation is closely connected with problems of micro-evolution and prediction of the fate of irradiated populations. This report gives new materials on radio-adaptation of small mammals inhabiting the East Ural Radioactive Trace (EURT) which has been formed after the Kyshtym accident in 1957 year. The EURT zone is a unique area for studying long-term consequences of chronic low-dose irradiation of small mammal populations many generations being born after the accident. The role of natural radioresistance, ecological specialization and biological characteristics of a specie in the development of radio-adaptation are discussed. The objects of investigation were rodents: 1) Ellobius talpinus is a peculiar specialized specie with low ability to migrate, burrowing underground way of life and lifespan up to 6 years; 2) Sylvaemus uralensis, Apodemus agrarius, Clethrionomys rutilus widespread aboveground species, very active migrators with a 1.5 year lifespan. Significant differences were found among species in natural radioresistance to acute gamma-irradiation. LD{sub 50/30} is 5.0{+-}0.7 Gy for the Ellobius talpinus, 7.0{+-}0.4 Gy for the Sylvaemus uralensis, 10.0{+-}0.2 Gy for the Apodemus agrarius, 12.8{+-}0.2 Gy for the Clethrionomys rutilus. Despite the high radiosensitivity the Ellobius talpinus was more tolerant to chronic irradiation (over 45 years inhabiting the EURT, soil pollution by {sup 90}Sr was 950-1050 Ci/km{sup 2} - 35-39 MBq/m{sup 2}) in a complex of morpho-physiological, haematological and immunological parameters, than other species with active migration activity (the initial pollution of soil by {sup 90}Sr was 400-540 Ci/km{sup 2} - 15-20 MBq/m{sup 2}). This phenomenon is explained by radio-adaptation which developed in the Ellobius talpinus due to isolation of their settlement in the periphery of the area in conditions of radio-contamination. Various radioresistance to acute and chronic irradiation, disproportion of

  16. Polyandry and polygyny in an African rodent pest species, Mastomys natalensis

    DEFF Research Database (Denmark)

    Kennis, Jan; Sluydts, Vincent; Leirs, Herwig

    2008-01-01

    removal and capture-mark-recapture techniques combined with microsatellite analyses. In total, 36 litters (359 young) and 94 candidate fathers were genotyped. Multiple paternity (more than one male per litter) occurs frequently in all sampled grids (>47% of all litters). Paternity assignment success rates...... are relatively high (mean 69%). Males are polygynous, but this is less frequent than female polyandry. Large differences in male reproductive success exist with a large part of the male population without offspring in our sample. Larger males father significantly more offspring. Spatial analyses do not show...... a strict spatial organisation. Our data suggest male M. natalensis roam around to mate with as many females as possible, while females also mate with several males to produce litters fathered by several males. This species could be an interesting candidate for testing virally vectored immunocontraception...

  17. Cone and seed traits of two Juniperus species influence roles of frugivores and scatter-hoarding rodents as seed dispersal agents

    Science.gov (United States)

    Dimitri, Lindsay A.; Longland, William S.; Vander Wall, Stephen B.

    2017-11-01

    Seed dispersal in Juniperus is generally attributed to frugivores that consume the berry-like female cones. Some juniper cones are fleshy and resinous such as those of western juniper (Juniperus occidentalis), while others are dry and leathery such as those of Utah juniper (J. osteosperma). Rodents have been recorded harvesting Juniperus seeds and cones but are mostly considered seed predators. Our study sought to determine if rodents play a role in dispersal of western and Utah juniper seeds. We documented rodent harvest of cones and seeds of the locally-occurring juniper species and the alternate (non-local) juniper species in removal experiments at a western juniper site in northeastern California and a Utah juniper site in western Nevada. Characteristics of western and Utah juniper cones appeared to influence removal, as cones from the local juniper species were preferred at both sites. Conversely, removal of local and non-local seeds was similar. Piñon mice (Peromyscus truei) were responsible for most removal of cones and seeds at both sites. We used radioactively labeled seeds to follow seed fate and found many of these seeds in scattered caches (western juniper: 415 seeds in 82 caches, 63.0% of seeds found; Utah juniper: 458 seeds in 127 caches, 39.5% of seeds found) most of which were attributed to piñon mice. We found little evidence of frugivores dispersing Utah juniper seeds, thus scatter-hoarding rodents appear to be the main dispersal agents. Western juniper cones were eaten by frugivores, and scatter-hoarding is a complimentary or secondary form of seed dispersal. Our results support the notion that Utah juniper has adapted to xeric environments by conserving water through the loss of fleshy fruits that attract frugivores and instead relies on scatter-hoarding rodents as effective dispersal agents.

  18. Diet choice patterns in rodents depend on novelty of the diet, exercise, species, and sex.

    Science.gov (United States)

    Yang, Tiffany; Xu, Wei-Jie; York, Haley; Liang, Nu-Chu

    2017-07-01

    Prolonged consumption of a palatable, high fat (HF) diet paired with a lack of physical activity can exacerbate the development of obesity. Exercise can facilitate the maintenance of a healthy body weight, possibly though mediating changes in diet preference. Using a two-diet choice and wheel running (WR) paradigm, our laboratory previously demonstrated that WR induces HF diet avoidance with different persistency in male and female rats when HF diet and WR are introduced simultaneously. The aims of this study were to examine whether this behavior is species dependent and to what extent the novelty of the diet affects WR induced HF diet avoidance. Experiment 1 utilized male C57BL6 mice in a two-diet choice and WR paradigm. Results show that all mice preferred HF to chow diet regardless of exercise and the order in which exercise and HF diet were presented. Experiment 2A (diet novelty) utilized Sprague-Dawley rats that were first habituated to a 45% HF diet prior to the simultaneous introduction of WR and a novel high-carbohydrate, low-fat (DK) diet. All rats avoided the novel high-carbohydrate diet and neither male nor female wheel running rats exhibited reduction in HF diet intake or HF diet avoidance. After all rats were returned to a sedentary condition, female rats consumed significantly more of the DK diet than the male rats. In Experiment 2B (diet familiarity), rats remained sedentary and were re-habituated to the DK diet until intake stabilized. Subsequently, a 60% HF diet was introduced for all rats and for running rats, access to the running wheels were provided simultaneously. Consistent with our previous findings, HF diet intake and preference was significantly reduced in all wheel running rats. These data suggest that exercise induced HF diet avoidance is affected by species and the novelty of the diet. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Re-emergence of tularemia in Germany: Presence of Francisella tularensis in different rodent species in endemic areas

    Directory of Open Access Journals (Sweden)

    Pfeffer Martin

    2008-11-01

    Full Text Available Abstract Background Tularemia re-emerged in Germany starting in 2004 (with 39 human cases from 2004 to 2007 after over 40 years of only sporadic human infections. The reasons for this rise in case numbers are unknown as is the possible reservoir of the etiologic agent Francisella (F. tularensis. No systematic study on the reservoir situation of F. tularensis has been published for Germany so far. Methods We investigated three areas six to ten months after the initial tularemia outbreaks for the presence of F. tularensis among small mammals, ticks/fleas and water. The investigations consisted of animal live-trapping, serologic testing, screening by real-time-PCR and cultivation. Results A total of 386 small mammals were trapped. F. tularensis was detected in five different rodent species with carrier rates of 2.04, 6.94 and 10.87% per trapping area. None of the ticks or fleas (n = 432 tested positive for F. tularensis. We were able to demonstrate F. tularensis-specific DNA in one of 28 water samples taken in one of the outbreak areas. Conclusion The findings of our study stress the need for long-term surveillance of natural foci in order to get a better understanding of the reasons for the temporal and spatial patterns of tularemia in Germany.

  20. FAKTOR-FAKTOR YANG BERHUBUNGAN DENGAN KEJADIAN ASCARIASIS PADA MURID SEKOLAH DASAR

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    Atikah Mardhika Ihsan

    2015-09-01

    Full Text Available AbstrakKejadian Ascariasis masih tinggi di Kota Padang, terutama pada anak usia sekolah dasar. Banyak faktor yang mempengaruhi tingginya kejadian Ascariasis ini. Tujuan penelitian ini adalah untuk mengetahui faktor-faktor yang berhubungan dengan kejadian Ascariasis pada murid Sekolah Dasar. Penelitian ini merupakan penelitian analitik dengan metode cross sectional study yang dilakukan pada 122 murid SDN 25 dan 28 Purus, Kota Padang pada bulan Desember 2013. Faktor-faktor yang diteliti antara lain higienitas perorangan, tingkat pengetahuan ibu, sanitasi lingkungan, tempat tinggal, dan tingkat penghasilan orang tua. Hubungan antar variabel dianalisis dengan uji chi-square. Hasil penelitian menunjukkan bahwa murid yang positif Ascariasis sebesar 34,4%. Kejadian Ascariasis ditemukan pada murid yang higienitas perorangan kurang baik sebesar 52%, tingkat pengetahuan ibu yang rendah sebesar 34,9%, sanitasi lingkungan yang kurang baik sebesar 29,3%, dan tingkat penghasilan orang tua yang rendah sebesar 37%. Analisis statistik menunjukkan tidak terdapat hubungan bermakna antara higienitas perorangan (p=0.06, pengetahuan ibu (p=1, sanitasi lingkungan (p=0,35, dan tingkat penghasilan orang tua (p=0,59 dengan kejadian Ascariasis. Kesimpulan: Kejadian Ascariasis pada pada murid SDN 25 dan 28 Purus, Kota Padang tahun 2013 tidak berkaitan dengan higienitas perorangan, pengetahuan ibu, sanitasi lingkungan, dan tingkat penghasilan orang tua.AbstractThe prevalence of Ascariasis is still high in Padang, especially at primary school age children. There are many factors contribute to the high incidence of this Ascariasis. The purpose of this study was to know the factors that associated with the incidence of Ascariasis in primary school. This study uses an analytical design method of cross -sectional study on 122 students in 25 and 28 primary school Purus, Padang in December 2013. The factors studied include personal hygiene, level of maternal knowledge, sanitary

  1. Time management in a co-housed social rodent species (Arvicanthis niloticus).

    Science.gov (United States)

    Castillo-Ruiz, Alexandra; Indic, Premananda; Schwartz, William J

    2018-01-19

    Sociality has beneficial effects on fitness, and timing the activities of animals may be critical. Social cues could influence daily rhythmic activities via direct effects on the circadian clock or on processes that bypass it (masking), but these possibilities remain incompletely addressed. We investigated the effects of social cues on the circadian body temperature (Tb) rhythms in pairs of co-housed and isolated grass rats, Arvicanthis niloticus (a social species), in constant darkness (DD). Cohabitation did not induce synchronization of circadian Tb rhythms. However, socio-sexual history did affect circadian properties: accelerating the clock in sexually experienced males and females in DD and advancing rhythm phase in the females in a light-dark cycle. To address whether synchronization occurs at an ultradian scale, we analyzed Tb and activity rhythms in pairs of co-housed sisters or couples in DD. Regardless of pair type, co-housing doubled the percentage of time individuals were simultaneously active without increasing individual activity levels, suggesting that activity bouts were synchronized by redistribution over 24 h. Together, our laboratory findings show that social cues affect individual "time allocation" budgets via mechanisms at multiple levels of biological organization. We speculate that in natural settings these effects could be adaptive, especially for group-living animals.

  2. Convergent and Divergent Adaptations of Subterranean Rodents

    DEFF Research Database (Denmark)

    Fang, Xiaodong

    Subterranean rodents comprise approximately 250 species that spend their entire lives in underground, unventilated tunnels, distributed along all continents except Australia and Antarctica. Subterranean rodents escape from predators and extreme climatic fluctuations in their underground habitats,...

  3. How many species of mammals are there in Brazil? New records of rare rodents (Rodentia: Cricetidae: Sigmodontinae from Amazonia raise the current known diversity

    Directory of Open Access Journals (Sweden)

    Alexandre R. Percequillo

    2017-12-01

    Full Text Available Background Since 1996, when Vivo questioned how many species of mammals occur in Brazil, there has been a huge effort to assess this biodiversity. In this contribution, we present new records for rare species of the sigmodontine rodent genera Rhagomys and Neusticomys previously unknown to Brazilian Amazon. We provided detailed information on the morphologic variation to allow the proper identification of these species. We also furnished updated information on their collection, aiming to establish hypothesis of their geographic distribution, based on SDM’s, aiming to hypothesize potential occurrence areas for these species. Methods Rodent specimens were sampled in separate inventories in two sites of Rondônia State (Hydroelectric Dam Jirau and Parque Nacional de Pacaás Novos and one site in Pará State (Pacajá, Brazil, and were compared to specimens from museum collections to apply appropriate names. The SDM were conducted using two algorithms for rare species, MaxEnt and randomForest (RF, and were based on seven localities for Rhagomys, and 10 for Neusticomys. Results All specimens were collected with pitfall traps. One specimen of genus Rhagomys was trapped in the Hydroelectric Dam Jirau. We identified this specimen as R. longilingua, and the SDM species indicates suitable areas for its occurrence at high elevations near on the Andes and lowlands of Amazon Basin to the South of the Rio Amazonas. Two specimens of Neusticomys were recorded, and we identified the specimen from Pacaás Novos as N. peruviensis, with SDM suggesting main areas of occurrence on Western Amazon. We applied the name N. ferreirai to the specimen from Pacajá, with SDM recovering suitable areas in Eastern Amazon. Discussion We reinforced the importance of pitfall traps on the study of Neotropical rodents. We described morphologic variation within and among all species that do not invalidate their specific status, but in the near future a re-evaluation will be mandatory

  4. Late Quaternary climatic vegetational shifts in an ecological transition zone of northern Madagascar: insights from genetic analyses of two endemic rodent species.

    Science.gov (United States)

    Rakotoarisoa, J-E; Raheriarisena, M; Goodman, S M

    2013-05-01

    The Loky-Manambato region, located in northern Madagascar, is a biotically rich contact zone between different forest biomes. Local current forest cover is composed of both humid and dry formations, which show elevational stratification. A recent phylogeographical study of a regional dry forest rodent, Eliurus carletoni (subfamily Nesomyinae), found genetic evidence of forest contractions between 18 750 and 7500 years BP, which based on extrapolation of the pollen subfossil record, was thought to be associated with an expansion of local humid forests. Herein, we conduct a genetic test of this hypothesis and focused on populations on two neighbouring massifs of forest-dependent rodent species, one associated with low-elevation dry forests (E. carletoni) and the other with higher elevation humid forests (Eliurus tanala). Using mitochondrial markers and a combination of traditional and coalescent-based phylogeographical, historical demographic and population genetic methods, we found evidence of historical connections between populations of E. tanala. Adjacent populations of E. carletoni and E. tanala exhibit opposite historical demographic patterns, and for both, evidence suggests that historical demographic events occurred within the last 25 000 years BP. These findings strongly support the proposed late Quaternary shifts in the floristic composition of the Loky-Manambato region. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  5. Comparative Ultrastructural Studies on the Impact of Moderate and Hyperthermic Environment on the Corneal Structure of two Species of Wild Rodents

    International Nuclear Information System (INIS)

    Naguib, N.I.; El-Dawi, E.F.

    2011-01-01

    This study was carried out to investigate the impact of environmental climate (temperature) on the corneal structure of two wild rodents; the nocturnal Norway rats (Rattus norvegicus) and the diurnal golden spiny mouse (Acomys russatus). Both rodents were collected from two extreme climatic environment and their dissected corneas were prepared for light, scanning and transmission electron microscopy. The corneas of both rodents are composed of three main layers; an outer epithelium, stroma, Descemet's membrane, and an inner endothelium. The mean thickness of the epithelium, stroma, Descemet's membrane and inner endothelium of both rodents were measured. The scanning electron microscopy revealed that in R. norvegicus and A. russatus; the outermost cells of the corneal epithelium, are mostly polygonal in shape with nearly regular borders and show dense pattern of microplicae with different scatter electron that exhibits three polymorphic appearances (A, B, C) and two (A, B), respectively. Numerous A-light cells with dense microplicae, many B-dark cells with a moderate density of microplicae and few C-dark cells with a less density of microplicae were observed. Using transmission electron microscope, the epithelial cells of both species possess glycocalyx and the cytokeratin filaments are more extensive in the apical epithelial cells in A. russatus. The stroma in R. norvegicus is formed of outer and inner lamellar zones with spaces in between its wavy bundles. In A. russatus, the stroma is formed of one lamellar zone of flattened bundles of highly wavy and branched collagen fibrils. On the other hand, the surface of the endothelial cells in R. norvegicus is slightly bulging with many blebs whereas it showed flattened and nearly smooth surface in A. russatus. In conclusion, the differences in the number of the superficial epithelial cells and the thickness of the stroma and structure of the endothelium of R. norvegicus (nocturnal) and A. russatus (diurnal) are most

  6. Tool-use training in a species of rodent: the emergence of an optimal motor strategy and functional understanding.

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    Kazuo Okanoya

    Full Text Available BACKGROUND: Tool use is defined as the manipulation of an inanimate object to change the position or form of a separate object. The expansion of cognitive niches and tool-use capabilities probably stimulated each other in hominid evolution. To understand the causes of cognitive expansion in humans, we need to know the behavioral and neural basis of tool use. Although a wide range of animals exhibit tool use in nature, most studies have focused on primates and birds on behavioral or psychological levels and did not directly address questions of which neural modifications contributed to the emergence of tool use. To investigate such questions, an animal model suitable for cellular and molecular manipulations is needed. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrated for the first time that rodents can be trained to use tools. Through a step-by-step training procedure, we trained degus (Octodon degus to use a rake-like tool with their forelimbs to retrieve otherwise out-of-reach rewards. Eventually, they mastered effective use of the tool, moving it in an elegant trajectory. After the degus were well trained, probe tests that examined whether they showed functional understanding of the tool were performed. Degus did not hesitate to use tools of different size, colors, and shapes, but were reluctant to use the tool with a raised nonfunctional blade. Thus, degus understood the functional and physical properties of the tool after extensive training. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that tool use is not a specific faculty resulting from higher intelligence, but is a specific combination of more general cognitive faculties. Studying the brains and behaviors of trained rodents can provide insights into how higher cognitive functions might be broken down into more general faculties, and also what cellular and molecular mechanisms are involved in the emergence of such cognitive functions.

  7. Molecular characterization and specific detection of Anaplasma species (AP-sd) in sika deer and its first detection in wild brown bears and rodents in Hokkaido, Japan.

    Science.gov (United States)

    Moustafa, Mohamed Abdallah Mohamed; Lee, Kyunglee; Taylor, Kyle; Nakao, Ryo; Sashika, Mariko; Shimozuru, Michito; Tsubota, Toshio

    2015-12-01

    A previously undescribed Anaplasma species (herein referred to as AP-sd) has been detected in sika deer, cattle and ticks in Japan. Despite being highly similar to some strains of A. phagocytophilum, AP-sd has never been detected in humans. Its ambiguous epidemiology and the lack of tools for its specific detection make it difficult to understand and interpret the prevalence of this Anaplasma species. We developed a method for specific detection, and examined AP-sd prevalence in Hokkaido wildlife. Our study included 250 sika deer (Cervus nippon yesoensis), 13 brown bears (Ursus arctos yesoensis) and 252 rodents including 138 (Apodemus speciosus), 45 (Apodemus argenteus), 42 (Myodes rufocanus) and 27 (Myodes rutilus) were collected from Hokkaido island, northern Japan, collected during 2010 to 2015. A 770 bp and 382 bp segment of the 16S rRNA and gltA genes, respectively, were amplified by nested PCR. Results were confirmed by cloning and sequencing of the positive PCR products. A reverse line blot hybridization (RLB) based on the 16S rRNA gene was then developed for the specific detection of AP-sd. The prevalence of AP-sd by nested PCR in sika deer was 51% (128/250). We detected this Anaplasma sp. for the first time in wild brown bears and rodents with a prevalence of 15% (2/13) and 2.4% (6/252), respectively. The sequencing results of the 16S rRNA and gltA gene amplicons were divergent from the selected A. phagocytophilum sequences in GenBank. Using a newly designed AP-sd specific probe for RLB has enabled us to specifically detect this Anaplasma species. Besides sika deer and cattle, wild brown bears and rodents were identified as potential reservoir hosts for AP-sd. This study provided a high throughput molecular method that specifically detects AP-sd, and which can be used to investigate its ecology and its potential as a threat to humans in Japan. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Reticulate Pleistocene evolution of Ethiopian rodent genus along remarkable altitudinal gradient.

    Science.gov (United States)

    Bryja, Josef; Kostin, Danila; Meheretu, Yonas; Šumbera, Radim; Bryjová, Anna; Kasso, Mohammed; Mikula, Ondřej; Lavrenchenko, Leonid A

    2018-01-01

    The Ethiopian highlands are the most extensive complex of mountainous habitats in Africa. The presence of the Great Rift Valley (GRV) and the striking elevational ecological gradients inhabited by recently radiated Ethiopian endemics, provide a wide spectrum of model situations for evolutionary studies. The extant species of endemic rodents, often markedly phenotypically differentiated, are expected to possess complex genetic features which evolved asa consequence of the interplay between geomorphology and past climatic changes. In this study, we used the largest available multi-locus genetic dataset of the murid genus Stenocephalemys (347 specimens from ca 40 localities across the known distributional area of all taxa) to investigate the relative importance of disruptive selection, temporary geographic isolation and introgression in their adaptive radiations in the Pleistocene. We confirmed the four main highly supported mitochondrial (mtDNA) clades that were proposed as four species in a previous pilot study: S. albipes is a sister species of S. griseicauda (both lineages are present on both sides of the GRV), while the second clade is formed by two Afro-alpine species, S. albocaudata (east of GRV) and the undescribed Stenocephalemys sp. A (west of GRV). There is a clear elevational gradient in the distribution of the Stenocephalemys taxa with two to three species present at different elevations of the same mountain range. Surprisingly, the nuclear species tree corresponded only a little to the mtDNA tree. Multispecies coalescent models based on six nuclear markers revealed the presence of six separate gene pools (i.e. candidate species), with different topology. Phylogenetic analysis, together with the geographic distribution of the genetic groups, suggests a complex reticulate evolution. We propose a scenario that involves (besides classical allopatric speciation) two cases of disruptive selection along the elevational ecological gradient, multiple crosses of

  9. Diurnal rodents as animal models of human central vision: characterisation of the retina of the sand rat Psammomys obsesus.

    Science.gov (United States)

    Saïdi, Tounès; Mbarek, Sihem; Chaouacha-Chekir, Rafika Ben; Hicks, David

    2011-07-01

    Cone photoreceptor-based central vision is of paramount importance in human eyesight, and the increasing numbers of persons affected by macular degeneration emphasizes the need for relevant and amenable animal models. Although laboratory mice and rats have provided valuable information on retinal diseases, they have inherent limitations for studies on macular pathology. In the present study, we extend our recent analyses of diurnal murid rodents to demonstrate that the sand rat Psammomys obesus has a remarkably cone-rich retina, and represents a useful adjunct to available animal models of central vision. Adult P. obesus were captured and transferred to animal facilities where they were maintained under standard light/dark cycles. Animals were euthanised and their eyes enucleated. Tissue was either fixed in paraformaldehyde and prepared for immunohistochemistry, or solubilized in lysis buffer and separated by SDS-PAGE and subjected to western blot analysis. Samples were labelled with a battery of antibodies against rod and cone photoreceptors, inner retinal neurones, and glia. P. obesus showed a high percentage of cones, 41% of total photoreceptor numbers in both central and peripheral retina. They expressed multiple cone-specific proteins, including short and medium-wavelength opsin and cone transducin. A second remarkable feature of the retina concerned the horizontal cells, which expressed high levels of glial fibrillar acidic protein and occludin, two proteins which are not seen in other species. The retina of P. obesus displays high numbers of morphologically and immunologically identifiable cones which will facilitate analysis of cone pathophysiology in this species. The unusual horizontal cell phenotype may be related to the cone distribution or to an alternative facet of the animals lifestyle.

  10. Urban resident attitudes toward rodents, rodent control products, and environmental effects

    Science.gov (United States)

    Rodent control in urban areas can result in the inadvertent mortality of non-target species (e.g., bobcats). However, there is little detailed information about rodent control practices of urban residents. Our objective was to evaluate urban rodent control behaviors in two area...

  11. Pig BMSCs Transfected with Human TFPI Combat Species Incompatibility and Regulate the Human TF Pathway in Vitro and in a Rodent Model

    Directory of Open Access Journals (Sweden)

    Hongchen Ji

    2015-05-01

    Full Text Available Background: The activation of tissue factor (TF is one of the major reasons for coagulation dysregulation after pig-to-primate xenotransplantation. Tissue factor pathway inhibitor (TFPI is the most important inhibitor of TF. Studies have demonstrated species incompatibility between pig TFPI and human TF. Methods: A pig-to-macaque heterotopic auxiliary liver transplantation model was established to determine the origin of activated TF. Chimeric proteins of human and pig TFPI were constructed to assess the role of Kunitz domains in species incompatibility. Immortalised pig bone marrow mesenchymal stem cells transfected with human TFPI were tested for their ability to inhibit clotting in vitro. Results: TF from recipient was activated early after liver xenotransplantation. Pig TFPI Kunitz domain 2 bound human FXa, but Kunitz domain 1 did not effectively inhibit human TF/FVIIa. Immortalised pig bone marrow mesenchymal cells (BMSCs transfected with human TFPI showed a prolonged recalcification time in vitro and in a rodent model. Conclusion: Recipient TF is relevant to dysregulated coagulation after xenotransplantation. Kunitz domain 1 plays the most important role in species incompatibility between pig TFPI and human TF, and clotting can be inhibited by human TFPI-transfected pig BMSCs. Our study shows a possible way to resolve the incompatibility of pig TFPI.

  12. Thermoregulation of the subterranean rodent genus Bathyergus ...

    African Journals Online (AJOL)

    The thermoregulation of the largest subterranean rodent, genus Bathyergus, comprising two species, B. suillus and B. janetta,occurring in mesic and semiarid habitats respectively, was investigated and compared with that of other subterranean rodents. Both species display low resting metabolic rates and low body ...

  13. DNA-based and geometric morphometric analysis to validate species designation: a case study of the subterranean rodent Ctenomys bicolor.

    Science.gov (United States)

    Stolz, J F B; Gonçalves, G L; Leipnitz, L; Freitas, T R O

    2013-10-25

    The genus Ctenomys (Rodentia: Ctenomyidae) shows several taxonomic inconsistencies. In this study, we used an integrative approach including DNA sequences, karyotypes, and geometric morphometrics to evaluate the taxonomic validity of a nominal species, Ctenomys bicolor, which was described based on only one specimen in 1912 by Miranda Ribeiro, and since then neglected. We sampled near the type locality assigned to this species and collected 10 specimens. A total of 820 base pairs of the cytochrome b gene were sequenced and analyzed together with nine other species and four morphotypes obtained from GenBank. Bayesian analyses showed that C. bicolor is monophyletic and related to the Bolivian-Matogrossense group, a clade that originated about 3 mya. We compared the cranial shape through morphometric geometrics of C. bicolor, including the specimen originally sampled in 1912, with other species representative of the same phylogenetic group (C. boliviensis and C. steinbachi). C. bicolor shows unique skull traits that distinguish it from all other currently known taxa. Our findings confirm that the specimen collected by Miranda Ribeiro is a valid species, and improve the knowledge about Ctenomys in the Amazon region.

  14. 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.

  15. Response of the dominant rodent species to close-to-nature logging practices in a temperate mixed forest

    Directory of Open Access Journals (Sweden)

    Peter Lešo

    2016-12-01

    Full Text Available The paper aims to answer the question whether differences exist in microhabitat preferences of the yellow-necked mouse and the bank vole between the natural forest and close-to-nature managed forest in the phase of stand regeneration. The two species were live-trapped during two periods in 2006 and 2007 on a square trapping grid established in a managed forest and a natural one. Ten microhabitat variables of each trapping point were measured to analyse their influence on the spatial distribution of the two species. At trapping points, the number of capture records for each species as a dependent variable was modelled using Generalised Linear Models. The herbal cover and a distance to the nearest woody debris were the most important measured microhabitat variables which affect the spatial distribution of both species. In the natural forest, the number of captures in both species increased significantly (p < 0.05 with a decreasing number of trees, increasing undergrowth coverage and decreasing distance to the nearest woody debris. In the managed forest, an increasing distance to the nearest tree and increasing herbal cover had a negative effect on the yellow-necked mouse occurrence (p < 0.001, while in contrast, the increase in values of the same variables increased frequency of occurrence of the bank vole (p < 0.001. Moreover, the bank vole was more frequent in the presence of woody debris (p < 0.002. The study demonstrated clearly that these species modify their spatial activity depending on the management of the woodland.

  16. Systematic studies of Oryzomyine rodents (Muridae, Sigmodontinae): diagnoses and distributions of species formerly assigned to Oryzomys 'capito'

    Science.gov (United States)

    Musser, G.G.; Carleton, M.D.; Brothers, E.M.; Gardner, A.L.

    1998-01-01

    We describe the morphological species-boundaries and geographic distributions of ten Neotropical Oryzomys based on analyses of museum specimens (skins and skulls, examples preserved in fluid, chromosomal spreads, and information about collection sites from skin tags, field catalogs, and other sources). These species have been regarded as members of an Oryzomys capito complex and for a long time were consolidated into a single entity identified as O. capito. Our study documents the following: 1. Defining the limits of species within the O. capito complex first requires a comprehensive review and rigorous definition of O. capito itself. We consider Fischer's (1814) Mus megacephalus to be valid and available, designate a neotype to bear the name, and reinstate it as a senior synonym of capito Olfers (1818). We then provide a working definition of O. megacephalus and its close relative, O. laticeps, derived from analyses of morphometric variation, estimates of geographic distributions, and evaluations of synonyms. In our view, O. megacephalus occurs in Amazonia but also extends into eastern Paraguay; its synonyms are capito Olfers (1818), cephalotes Desmarest (1819), velutinus Allen and Chapman (1893), goeldi Thomas (1897), modestus Allen (1899), and perenensis Allen (1901). Oryzomys laticeps Lund (1840) occurs in the Atlantic Forest region of eastern Brazil. We designate a lectotype for laticeps and allocate the names saltator Winge (1887) and oniscus Thomas (1904) as synonyms. 2. We provide the first comprehensive taxonomic revision of Oryzomys yunganus Thomas (1902). Its range covers tropical evergreen rainforest formations in the Guiana region and the Amazon Basin where, as documented by voucher specimens, it has been collected at the same localities as O. megacephalus, O. nitidus, and O. tern of carotid arterial circulation, occlusal patterns of second upper and lower molars, cranial proportions, and chromosomal features. Appreciable intraspecific geographic

  17. Dietary patterns of two herbivorous rodents: and Parotomys brantsii ...

    African Journals Online (AJOL)

    Frequency of occurrence of plant species in the diets were compared with availability of the plants in the rodents' habitats. Both rodents are generalist herbivores, eating plants species in proportion to the availability in their habitats. Dietary patterns, diversity of diet and degree of overlap between rodent's diets are a function ...

  18. Species and Sex Differences in the Morphogenic Response of Primary Rodent Neurons to 3,3'-Dichlorobiphenyl (PCB 11).

    Science.gov (United States)

    Sethi, Sunjay; Keil, Kimberly P; Lein, Pamela J

    2017-12-23

    PCB 11 is an emerging global pollutant that we recently showed promotes axonal and dendritic growth in primary rat neuronal cell cultures. Here, we address the influence of sex and species on neuronal responses to PCB 11. Neuronal morphology was quantified in sex-specific primary hippocampal and cortical neuron-glia co-cultures derived from neonatal C57BL/6J mice and Sprague Dawley rats exposed for 48 h to vehicle (0.1% DMSO) or PCB 11 at concentrations ranging from 1 fM to 1 nM. Total axonal length was quantified in tau-1 immunoreactive neurons at day in vitro (DIV) 2; dendritic arborization was assessed by Sholl analysis at DIV 9 in neurons transfected with MAP2B-FusRed. In mouse cultures, PCB 11 enhanced dendritic arborization in female, but not male, hippocampal neurons and male, but not female, cortical neurons. In rat cultures, PCB 11 promoted dendritic arborization in male and female hippocampal and cortical neurons. PCB 11 also increased axonal growth in mouse and rat neurons of both sexes and neuronal cell types. These data demonstrate that PCB 11 exerts sex-specific effects on neuronal morphogenesis that vary depending on species, neurite type, and neuronal cell type. These findings have significant implications for risk assessment of this emerging developmental neurotoxicant.

  19. Wild Rodent Ectoparasites Collected from Northwestern Iran

    Directory of Open Access Journals (Sweden)

    Zabihollah Zarei

    2017-04-01

    Full Text Available Background: Rodents play an important role as reservoir of some pathogens, and the host of some ectoparasites as well. These ectoparasites can transmit rodents’ pathogens to human or animals. The aim of this study was to assess the distribution and infestation load of ectoparasites on rodents in Meshkin-Shahr District, northwestern Iran.Method: Rodents were captured using baited live traps in spring 2014 from Meshkin-Shahr District and were trans­ferred to the laboratory for identification to the species level. Their ectoparasites were collected, mounted and identi­fied.Results: Three rodent species including Meriones persicus (74%, Mus musculus (16.9% and Cricetulus migrato­rius (9% were identified. Among all rodents, 185 specimens (90.69% were infested with a total of 521 ectopara­sites. Overall, 10 arthropods species were collected, including fleas (97.6%, one mite (1.6% and one louse species (0.6% as follows: Xenopsylla nubica, X. astia, X. buxtoni, X. cheopis, Nosopsyllus fasciatus, N. iranus, Cten­ocephalides felis, Ctenophthalmus rettigismiti, Ornithonyssus sp and one species of genus Polyplax. The most prev­alent ectoparasites species was X. nubica (89%.Conclusion: Nearly all rodent species were infested with Xenopsylla species. Monitoring of ectoparasites on infested rodents is very important for awareness and early warning towards control of arthropod-borne diseases.

  20. Identification of Putative Ortholog Gene Blocks Involved in Gestant and Lactating Mammary Gland Development: A Rodent Cross-Species Microarray Transcriptomics Approach

    Science.gov (United States)

    Rodríguez-Cruz, Maricela; Coral-Vázquez, Ramón M.; Hernández-Stengele, Gabriel; Sánchez, Raúl; Salazar, Emmanuel; Sanchez-Muñoz, Fausto; Encarnación-Guevara, Sergio; Ramírez-Salcedo, Jorge

    2013-01-01

    The mammary gland (MG) undergoes functional and metabolic changes during the transition from pregnancy to lactation, possibly by regulation of conserved genes. The objective was to elucidate orthologous genes, chromosome clusters and putative conserved transcriptional modules during MG development. We analyzed expression of 22,000 transcripts using murine microarrays and RNA samples of MG from virgin, pregnant, and lactating rats by cross-species hybridization. We identified 521 transcripts differentially expressed; upregulated in early (78%) and midpregnancy (89%) and early lactation (64%), but downregulated in mid-lactation (61%). Putative orthologous genes were identified. We mapped the altered genes to orthologous chromosomal locations in human and mouse. Eighteen sets of conserved genes associated with key cellular functions were revealed and conserved transcription factor binding site search entailed possible coregulation among all eight block sets of genes. This study demonstrates that the use of heterologous array hybridization for screening of orthologous gene expression from rat revealed sets of conserved genes arranged in chromosomal order implicated in signaling pathways and functional ontology. Results demonstrate the utilization power of comparative genomics and prove the feasibility of using rodent microarrays to identification of putative coexpressed orthologous genes involved in the control of human mammary gland development. PMID:24288657

  1. EKSPRESI VERBAL PENDERITA APRAXIA WICARA: KASUS GANGGUAN WICARA MURID SDN 2 BATU PUTIH KAB. BOMBANA

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    Batmang Batmang

    2016-05-01

    Full Text Available Abstract This study aimed to obtain factual data of the verbal expression of speech apraxia people in order to know the forms of verbal expressions of patients with apraxia speech in terms of aspects of phonological, lexical aspect, and description of non-linguistic abilities. The study was conducted in SD Negeri 2 Batuputih, Southeast Sulawesi with a single subject, a fourth-grade student who suffered speech apraxia. This research was a case study that examined the behavior of language of the speech apraxia patients. The techniques used in data collection are observation, recording, question and answer, and interviews. The instrument used in data collection is, the pictures of objects, field notes, interview guide, and voice recorder. The data analysis was done by using an error analysis and contrastive analysis. The results obtained: (1 in terms of phonological aspects, the speech apraxia patients tended to have difficulty in reciting the phoneme, (2 in terms of lexical aspect, the verbal expressions of the apraxia speech patients are not meaningful at all, what people said just the unmeaning sounds, (3 linguistically speech apraxia patients are unable to express themselves the meaningful words but the non-linguistic one, the observed patients did not show any symptoms of abnormality. Keywords: Apraxia speech, verbal expression, impaired speech   Abstrak Penelitian ini betujuan untuk memperoleh data faktual tentang ekspresi verbal penderita apraxia wicara agar dapat mengetahui bentuk-bentuk ekspresi verbal penderita apraxia wicara dalam hal aspek fonologi, aspek leksikal, dan gambaran tentang kemampuan non-linguistiknya. Penelitian dilakukan di SD Negeri 2 Batuputih, Sulawesi Tenggara dengan subjek tunggal seorang murid kelas IV yang menderita apraxia wicara. Penelitian ini mengkaji perilaku berbahasa pada penderita apraxia wicara. Teknik yang digunakan dalam pengumpulan data adalah: observasi, perekaman, tanya-jawab, dan wawancara. Alat yang

  2. Allometric disparity in rodent evolution

    OpenAIRE

    Wilson LAB

    2013-01-01

    In this study, allometric trajectories for 51 rodent species, comprising equal representatives from each of the major clades (Ctenohystrica, Muroidea, Sciuridae), are compared in a multivariate morphospace (=allometric space) to quantify magnitudes of disparity in cranial growth. Variability in allometric trajectory patterns was compared to measures of adult disparity in each clade, and dietary habit among the examined species, which together encapsulated an ecomorphological breadth. Results ...

  3. Identifikasi Carrier Bakteri Streptococcus β hemolyticus Group A pada Murid SD Negeri 13 Padang Berdasarkan Perbedaan Umur dan Jenis Kelamin

    Directory of Open Access Journals (Sweden)

    Fadhila Aini

    2016-01-01

    Full Text Available AbstrakStreptococcus β hemolyticus Grup A atau yang disebut juga Streptococcus pyogenes merupakan salah satu bakteri patogen yang banyak menginfeksi manusia.Bakteri ini dapat ditemukan sebagai carrier di saluran pernafasan terutama pada anak-anak, tidak menimbulkan penyakit tetapi berisiko untuk menyebarkan penyakit. Tujuan penelitian ini adalah menentukan jumlah carrier  bakteri Streptococcus β hemolyticus Grup A pada murid berdasarkan perbedaan umur dan jenis kelamin. Jenis penelitian ini adalah deskriptif cross-sectional dengan menggunakan sampel seluruh murid SD Negeri 13 Padang. Hasil penelitian adalah didapatkan 2 orang murid yang menderita carrier, yaitu pada kelompok usia>8-9 tahun dan >11 tahun. Berdasarkan jenis kelamin yang terdiri dari 54 orang laki-laki dan 50 orang perempuan, didapatkan 2 orang carrier yaitu hanya pada anak laki-laki. Hasil penelitian menunjukkan bahwa carrier bakteri Streptococcus β hemolyticus Group  A terdapat pada anak usia tersebut karena masih kurangnya pengetahuan tentang kebersihan. Carrier yang ditemukan hanya pada anak laki-laki kemungkinan disebabkan mereka lebih sering bermain di luar rumah dan terpapar dengan berbagai bakteri patogen dan kurang memperhatikan kebersihan diri.Kata kunci: carrier, streptococcus β hemolyticus grup A, umur, jenis kelamin AbstractGroup A Streptococcus β hemolyticus or also called Streptococcus pyogenes is one of many pathogenic bacteria that infect humans. These bacteria can be found as a carrier in the respiratory tract especially in children, do not cause disease but can be a risk for spreading the disease. This objective of this study was to determine the amount of the carrier of bacteria group A Streptococcus β hemolyticus based on age and gender differences. This research is a descriptive cross - sectional study using a sample of all students of SD Negeri 13 Padang. Based on the age of 104 students found that students who suffer 2 carrier, which is in the age

  4. Population dynamics of Rodents and Insectivores in lowland tropical ...

    African Journals Online (AJOL)

    The community structure of rodents and insectivores in the lowland tropical rainforest of Okomu National Park, Edo State, Nigeria was assessed using a combination of live-trapping and sighting techniques during the dry and wet seasons. Seventeen species (14 species of rodent, 3 species of insectivores) were captured, ...

  5. The Murid Herpesvirus-4 gL regulates an entry-associated conformation change in gH.

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    Laurent Gillet

    2008-07-01

    Full Text Available The glycoprotein H (gH/gL heterodimer is crucial for herpesvirus membrane fusion. Yet how it functions is not well understood. The Murid Herpesvirus-4 gH, like that of other herpesviruses, adopts its normal virion conformation by associating with gL. However, gH switched back to a gL-independent conformation after virion endocytosis. This switch coincided with a conformation switch in gB and with capsid release. Virions lacking gL constitutively expressed the down-stream form of gH, prematurely switched gB to its down-stream form, and showed premature capsid release with poor infectivity. These data argue that gL plays a key role in regulating a gH and gB functional switch from cell binding to membrane fusion.

  6. Faktor Risiko Asma Pada Murid Sekolah Dasar Usia 6-7 Tahun di Kota Padang

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    Afdal .

    2012-11-01

    Full Text Available Abstrak Latar belakang : Asma merupakan penyakit kronik yang sering dijumpai pada anak. Dilaporkan bahwa prevalens asma meningkat pada anak maupun dewasa. Usia 6-7 tahun merupakan periode dimana prevalens asma dan angka kunjungan ke rumah sakit karena asma lebih tinggi. Terjadinya asma dianggap sebagai interaksi yang kompleks antara faktor genetik dan faktor lingkungan. Faktor genetik sudah dibuktikan dari penelitian-penelitian sebelumnya, tetapi karakteristik faktor risiko lingkungan pada asma belum jelas. Apabila melihat derajat peningkatan kejadian asma, tidak mungkin hanya faktor genetik yang berperan, tetapi peran faktor lingkungan justru yang lebih besar. Tujuan : Untuk mengetahui prevalens dan faktor risiko asma pada anak SD usia 6-7 tahun di Kota Padang.Metoda : Suatu penelitian cross sectional di 20 SD di Kota Padang pada bulan Juni – November 2009 dengan jumlah sampel 879 orang. Terhadap setiap subjek dilakukan penelitian yaitu pembagian kuisioner ISAAC (international study of asthma and allergies in childhood untuk orang tua. Analisis data dilakukan dengan uji chi-square untuk variabel katagorik dan analisis multivariat dengan regresi logistik. Data dianalisis menggunakan peranti lunak komputer.Hasil : Prevalens asma pada murid SD usia 6-7 tahun di Kota Padang berdasarkan kuisioner ISAAC sebesar 8%. Faktor yang paling dominan berpengaruh terhadap kejadian asma adalah atopi ayah atau ibu, diikuti faktor berat badan lahir dan kebiasaan merokok pada ibu serta pemberian obat parasetamol. Sedangkan pemberian ASI dan kontak dengan unggas merupakan faktor protektif terhadap kejadian asma. Kata kunci: faktor risiko, asma, sekolah dasar Abstract Background: Background Asthma is a common chronic disease in children. It had been reported that the prevalence of asthma in children and adults was increasing. The age of 6-7 years is the period where the prevalence and the number of visits to the hospital because of asthma are higher. The

  7. Ecology of rodents at an old quarry in Zambia

    African Journals Online (AJOL)

    Ecology of rodents at an old quarry in Zambia. E.N. Chidumayo. Livingstone Museum, Zambia. An old quarry, 2,5 hain size near Livingstone in southern. Zambia was kill- and live-trapped between September 1974 and December 1976 to determine ecological relations among. rodent species inhabiting it. Seven species ...

  8. HUBUNGAN PENYAKIT GONDOK DENGAN KADAR YODIUM DALAM URIN MURID MADRASAH IBTIDAIYAH NEGERI (MIN KORONG GADANG KECAMATAN KURANJI KOTA PADANG

    Directory of Open Access Journals (Sweden)

    Yustini Alioes

    2010-09-01

    Full Text Available AbstrakYodium adalah komponen esensial dalam asupan makanan manusia, yang merupakan bagian dari hormone tiroid yaitu tiroksin (T4 and triiodotironin (T3. Hormon tersebut dibutuhkan untuk menjaga metabolism basal, metabolism sel, dan kesatuan jaringan tubuh. Hormone tiroid diperlukan dalam perkembangan system sarat janin dan bayi. Kekurangan asupan yodium dapat menyebabkan penyakit gondok, yaitu pembesaran kelenjar tiroid. Gondok endemic merupakan hasil dari peningkatan kerja kelenjar tiroid oleh Thyroid Stimulating Hormone (TSH dalam memaksimalkan penggunaan yodium yang tersedia, hal ini merupakan penyesuaian terhadap kekurangan yodium.Tujuan penelitian ini adalah untuk mengetahui hubungan penyakit gondok dengan kadar yodium dalam urin murid Madrasah Ibtidaiyah Negeri Korong Gadang Kecamatan Kuranji Kota Padang.Telah dilakukan penelitian pada 130 murid kelas II, III, IV, V dan VI di Madrasah Ibtidaiyah Negeri (MIN Korong Gadang Kecamatan Kuranji Kota Padang. Data tentang prestasi belajar didaptkan dari hasil ujian semester. Pertumbuhan fisik ditentukan berdasarkan berat badan dan tinggi badan.Selama penelitian ini didapatkan 80 anak (61,5% menderita penyakit gondok. Tidak didapatkan hubungan yang bermakna antara penyakit gondok dan kadar yodium dalam urin (p>0,05. Penelitian ini juga menemukan tidak terdapat hubungan antara penyakit gondok dan pertumbuhan fisik (p>0,05.Kata Kunci : Iodium, urin, hipertiroidAbstractIodine is an essential component of human diet, which part of thyroid hormones thyroxine (T4 and triiodothyronine (T3. These hormones are involved in the maintenance of metabolic rate, cellular metabolism and integrity of connective tissue. Thyroid hormones are necessary for the development of nervous system in the fetus and infant. Lack of dietary iodine is cause of goiter, an enlargement of the thyroid stimulating hormone (TSH to maximize the utilization of available iodine and thus respresents maladaption to iodine deficiency

  9. Phylogeography of a widespread sub-Saharan murid rodent Aethomys chrysophilus: the role of geographic barriers and paleoclimate in the Zambezian bioregion

    Czech Academy of Sciences Publication Activity Database

    Mazoch, Vladimír; Mikula, Ondřej; Bryja, Josef; Konvičková, Hana; Russo, I.-R.; Verheyen, E.; Šumbera, R.

    (2018) ISSN 0025-1461 R&D Projects: GA ČR GAP506/10/0983; GA ČR GA15-20229S Institutional support: RVO:68081766 Keywords : Aethomys chrysophilus * Aethomys ineptus * phylogeography * Plio-Pleistocene climate changes * Zambezian bioregion Subject RIV: EG - Zoology Impact factor: 0.805, year: 2016

  10. Public Health and Rodents: A Game of Cat and Mouse

    NARCIS (Netherlands)

    Meerburg, B.G.

    2015-01-01

    Rodents are the most abundant order of living mammals, distributed on every continent except Antarctic and represent 43 % of all mammalian species. Beside causing food losses and infrastructural damage, rodents can harbour pathogens that may cause serious problems to human and animal health.

  11. Leptospira and rodents in Cambodia : environmental determinants of infection

    OpenAIRE

    Ivanova, S.; Herbreteau, Vincent; Blasdell, K.; Chaval, Y.; Buchy, P.; Guillard, B.; Morand, S.

    2012-01-01

    We investigated infection of rodents and shrews by Leptospira spp. in two localities of Cambodia (Veal Renh, Kaev Seima) and in four types of habitat (forests, non-flooded lands, lowland rain-fed paddy fields, houses) during the wet and the dry seasons. Habitat preference was common, and rodent and shrew species were found only in houses or in rain-fed paddy fields or in forests. Among 649 small mammals trapped belonging to 12 rodent species and 1 shrew species, 71 of 642 animals tested were ...

  12. Epidemiology of Leptospira Transmitted by Rodents in Southeast Asia

    Science.gov (United States)

    Mielcarek, Mathilde; Tatard, Caroline; Chaval, Yannick; Suputtamongkol, Yupin; Buchy, Philippe; Jittapalapong, Sathaporn; Herbreteau, Vincent; Morand, Serge

    2014-01-01

    Background Leptospirosis is the most common bacterial zoonoses and has been identified as an important emerging global public health problem in Southeast Asia. Rodents are important reservoirs for human leptospirosis, but epidemiological data is lacking. Methodology/Principal Findings We sampled rodents living in different habitats from seven localities distributed across Southeast Asia (Thailand, Lao PDR and Cambodia), between 2009 to 2010. Human isolates were also obtained from localities close to where rodents were sampled. The prevalence of Leptospira infection was assessed by real-time PCR using DNA extracted from rodent kidneys, targeting the lipL32 gene. Sequencing rrs and secY genes, and Multi Locus Variable-number Tandem Repeat (VNTR) analyses were performed on DNA extracted from rat kidneys for Leptospira isolates molecular typing. Four species were detected in rodents, L. borgpetersenii (56% of positive samples), L. interrogans (36%), L. kirschneri (3%) and L. weilli (2%), which were identical to human isolates. Mean prevalence in rodents was approximately 7%, and largely varied across localities and habitats, but not between rodent species. The two most abundant Leptospira species displayed different habitat requirements: L. interrogans was linked to humid habitats (rice fields and forests) while L. borgpetersenii was abundant in both humid and dry habitats (non-floodable lands). Conclusion/Significance L. interrogans and L. borgpetersenii species are widely distributed amongst rodent populations, and strain typing confirmed rodents as reservoirs for human leptospirosis. Differences in habitat requirements for L. interrogans and L. borgpetersenii supported differential transmission modes. In Southeast Asia, human infection risk is not only restricted to activities taking place in wetlands and rice fields as is commonly accepted, but should also include tasks such as forestry work, as well as the hunting and preparation of rodents for consumption, which

  13. Native Rodent Species Are Unlikely Sources of Infection for Leishmania (Viannia) braziliensis along the Transoceanic Highway in Madre de Dios, Peru

    OpenAIRE

    Shender, Lisa A.; De Los Santos, Maxy; Montgomery, Joel M.; Conrad, Patricia A.; Ghersi, Bruno M.; Razuri, Hugo; Lescano, Andres G.; Mazet, Jonna A. K.

    2014-01-01

    An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-born...

  14. Contrasting patterns of diversity and population differentiation at the innate immunity gene toll-like receptor 2 (TLR2) in two sympatric rodent species.

    Science.gov (United States)

    Tschirren, Barbara; Andersson, Martin; Scherman, Kristin; Westerdahl, Helena; Råberg, Lars

    2012-03-01

    Comparing patterns of diversity and divergence between populations at immune genes and neutral markers can give insights into the nature and geographic scale of parasite-mediated selection. To date, studies investigating such patterns of selection in vertebrates have primarily focused on the acquired branch of the immune system, whereas it remains largely unknown how parasite-mediated selection shapes innate immune genes both within and across vertebrate populations. Here, we present a study on the diversity and population differentiation at the innate immune gene Toll-like receptor 2 (TLR2) across nine populations of yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) in southern Sweden. In yellow-necked mice, TLR2 diversity was very low, as was TLR2 population differentiation compared to neutral loci. In contrast, several TLR2 haplotypes co-occurred at intermediate frequencies within and across bank vole populations, and pronounced isolation by distance between populations was observed. The diversity and differentiation at neutral loci was similar in the two species. These results indicate that parasite-mediated selection has been acting in dramatically different ways on a given immune gene in ecologically similar and sympatric species. Furthermore, the finding of TLR2 population differentiation at a small geographical scale in bank voles highlights that vertebrate innate immune defense may be evolutionarily more dynamic than has previously been appreciated. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  15. Uus Multiphonic Rodent

    Index Scriptorium Estoniae

    2009-01-01

    Tartus tegutsenud eksperimentaal-rock-duo Opium Flirt Eestisse jäänud liige Erki Hõbe (paarimees Ervin Trofimov tegutseb Ungaris) annab välja oma teise sooloalbumi nime all Multiphonic Rodent, heliplaadi "Astral Dance" esitluskontsert toimub 5. veebruaril Tallinnas baaris Juuksur

  16. Aerial-broadcast application of diphacinone bait for rodent control in Hawai`i: Efficacy and non-target species risk assessment

    Science.gov (United States)

    Foote, David; Spurr, Eric B.; Lindsey, Gerald D.; Forbes Perry, Charlotte

    2015-01-01

    Introduced rats (Rattus rattus, R. exulans, and R. norvegicus) have been implicated in the decline or extinction of numerous species of plants and animals in Hawai‘i. This study investigated the efficacy of aerial-broadcast application of Ramik® Green baits containing 50 ppm (0.005%) diphacinone in reducing rat and mouse populations and the risk to non-target species. The study was undertaken in paired 45.56-ha treatment and non-treatment plots in Hawai‘i Volcanoes National Park. All 21 radio-collared rats in the treatment plot died within nine days of bait application, whereas none of the 18 radio-collared rats in the non-treatment plot died. There was a 99% drop in both the rat capture rate and percentage of non-toxic census bait blocks gnawed by rats in the treatment plot relative to the non-treatment plot three weeks after bait application. The only rat captured in the treatment plot three weeks after bait application was not ear-tagged (i.e., it was not a recapture), whereas 44% of the 52 rats captured in the non-treatment plot were ear-tagged. Most of the bait had disappeared from the forest floor within about one month of application. No birds likely to have eaten bait were found dead, although residues of diphacinone were found in the livers of three species of introduced seed-eating/omnivorous birds captured alive after bait application. No predatory birds were found dead one month or three months after bait application. The remains of a Hawaiian hawk (Buteo solitarius) were found six months after bait application, but it was not possible to determine the cause of death. This study demonstrated the efficacy of aerially broadcast diphacinone bait for control of rats and mice in Hawaiian montane forests, and was part of the dataset submitted to the U.S. Environmental Protection Agency for the national registration of a diphacinone bait for the control of rat populations in conservation areas.

  17. Hubungan Status Gizi dengan Status Sosial Ekonomi Keluarga Murid Sekolah Dasar di Daerah Pusat dan Pinggiran Kota Padang Lisbet Rimelfhi Sebataraja,

    Directory of Open Access Journals (Sweden)

    Lisbet Rimelfhi Sebataraja

    2014-05-01

    Full Text Available AbstrakStatus gizi anak secara tidak langsung berkaitan dengan faktor sosial ekonomi keluarga. Jika status sosial ekonomi rendah maka kebutuhan makanan keluarga akan kurang terpenuhi sehingga anak akan memiliki status gizi kurang. Tujuan penelitian ini adalah untuk mengetahui hubungan status gizi dan status sosial ekonomi keluarga murid SD di pusat dan pinggiran kota Padang. Suatu penelitian analitik secara cross sectional telah dilakukan terhadap 220 orang murid di SDN 08 Alang Lawas sebagai perwakilan SD di pusat kota Padang dan SDN 36 Koto Panjang sebagai perwakilan SD di pinggiran kota Padang. Pengumpulan data dilakukan melalui kuisioner, pengukuran tinggi, dan berat badan anak. Analisa data dilakukan dengan menggunakan uji statistik Chi-Square. Hasil penelitian didapatkan status gizi murid SD di pusat kota dengan tingkat sosial ekonomi baik sebesar 84,2% status gizi baik dan 6% status gizi kurang, sedangkan keluarga dengan tingkat sosial ekonomi rendah didapatkan 15,7% status gizi baik dan 0% status gizi kurang. Pada daerah pinggiran kota dengan status ekonomi baik didapatkan 15,8% status gizi baik dan 64,7% status gizi kurang, sedangkan pada keluarga dengan status ekonomi rendah didapatkan 84,3% status gizi baik dan 100% status gizi kurang. Dari uji Chi-Square didapatkan nilai pearson Chi-Square (x2 = 71.004 lebih besar dari nilai x2 tabel = 7,815 dan nilai probabilitas (p = 0,000 lebih kecil dari nilai probabilitas yang bermakna yaitu p < 0,05 berarti terdapat hubungan yang signifikan antara status gizi dengan status sosial ekonomi keluarga murid SD di pusat dan pinggiran kota Padang. Status gizi anak juga berhubungan dengan tingkat ekonomi keluarga, tingkat pendidikan ayah dan ibu serta jumlah anak dalam keluarga.Kata kunci: Status Gizi, Status Sosial Ekonomi, Pusat Kota, Pinggiran KotaAbstractNutritional status of children is indirectly related to socioeconomic factors. If the low socioeconomic status family meals needs will not

  18. Leptospira interrogans in Rodents from Cape Verde.

    Science.gov (United States)

    Plata-Luis, Josué; Foronda, Pilar; Martín-Alonso, Aaron; Feliu, Carlos; Alves, Joana; Gil, Horacio; Valladares, Basilio

    2016-11-01

    Leptospirosis is an important worldwide zoonotic disease that can infect both animals and humans. In most cases, leptospirosis is a nonspecific self-limiting illness, but some patients can develop a severe form with a high mortality. This study was carried out in Santiago Island, Cape Verde, in 2012-2013. A total of 62 wild rodents (Rattus rattus and Mus domesticus) were analyzed. The lipL32 gene, present only in pathogenic Leptospira spp., was amplified by PCR, and 16 samples were positive (25.8%). In both rodent species, Leptospira interrogans was identified. The results show the presence of pathogenic Leptospira in the three localities analyzed in Santiago. The presence of L. interrogans demonstrates a serious health risk for the population, since this species has been associated with the most severe form of leptospirosis, the Weil's disease in humans, a severe infection with jaundice, renal failure, and hemorrhage.

  19. Bone morphology of the hind limbs in two caviomorph rodents.

    Science.gov (United States)

    de Araújo, F A P; Sesoko, N F; Rahal, S C; Teixeira, C R; Müller, T R; Machado, M R F

    2013-04-01

    In order to evaluate the hind limbs of caviomorph rodents a descriptive analysis of the Cuniculus paca (Linnaeus, 1766) and Hydrochoerus hydrochaeris (Linnaeus, 1766) was performed using anatomical specimens, radiography, computed tomography (CT) and full-coloured prototype models to generate bone anatomy data. The appendicular skeleton of the two largest rodents of Neotropical America was compared with the previously reported anatomical features of Rattus norvegicus (Berkenhout, 1769) and domestic Cavia porcellus (Linnaeus, 1758). The structures were analyzed macroscopically and particular findings of each species reported. Features including the presence of articular fibular projection and lunulae were observed in the stifle joint of all rodents. Imaging aided in anatomical description and, specifically in the identification of bone structures in Cuniculus paca and Hydrochoerus hydrochaeris. The imaging findings were correlated with the anatomical structures observed. The data may be used in future studies comparing these animals to other rodents and mammalian species. © 2012 Blackwell Verlag GmbH.

  20. FUNGSI TASAWUF TERHADAP PEMBENTUKAN AKHLAK (ETIKA KERJA:Studi pada Murid Tarekat Qadiriyah Naqsyabandiyah di Kota Pontianak Kalimantan Barat

    Directory of Open Access Journals (Sweden)

    Fatmawati Fatmawati

    2016-03-01

    pembentukan akhlak (etika kerja para pengikutnya. Selanjutnya penelitian ini menggunakan pendekatan kualitatif dilengkapi dengan metode deskriptif. Penjaringan data penelitian ini meng¬gunakan teknik snow ball yakni pada informan pengikut perguruan tarekat Qadiriyah Naqsyabandiyah As-Salam dan An-Nuur di kota Pontianak dengan asumsi aliran QN lebih dominan di Pontianak. Tahapan selanjutnya data dianalisis dengan menggunakan analisis kualitatif. Hasil penelitian mengambarkan tahapan-tahahan pengamalan tasawuf oleh ikhsan/murid yang dibimbing oleh mursyid/guru seperti prosesi bai’at (ikrar dan prosesi zikir yang dilakukan secara konsisten berimplikasi pada akhlak (etika kerja yang mempunyai dimensi spiritual dan nilai-nilai Islami. Akhlak (etika kerja merujuk sifat-sifat Nabi Muhammad Saw seperti sifat ṣiddiq(benar, amanah (tangungjawab, faṭanah (kecerdasan dan tablīgh (promosi yang masih relevan hingga kini. Ketika melakukan aktivitas kerja para pengikut QN merasa mempunyai kekuatan spiritualdi dalam dirinya, yakni merasa selalu ada yang mengawasi. Mereka berhati-hati dalam bekerja dan selalu menjaga perilakunya sesuai akhlak Islami. Keywords: tasawuf, tarekat, akhlak, etika.

  1. Neurogenetics of aggressive behavior: studies in rodents.

    Science.gov (United States)

    Takahashi, Aki; Miczek, Klaus A

    2014-01-01

    Aggressive behavior is observed in many animal species, such as insects, fish, lizards, frogs, and most mammals including humans. This wide range of conservation underscores the importance of aggressive behavior in the animals' survival and fitness, and the likely heritability of this behavior. Although typical patterns of aggressive behavior differ between species, there are several concordances in the neurobiology of aggression among rodents, primates, and humans. Studies with rodent models may eventually help us to understand the neurogenetic architecture of aggression in humans. However, it is important to recognize the difference between the ecological and ethological significance of aggressive behavior (species-typical aggression) and maladaptive violence (escalated aggression) when applying the findings of aggression research using animal models to human or veterinary medicine. Well-studied rodent models for aggressive behavior in the laboratory setting include the mouse (Mus musculus), rat (Rattus norvegicus), hamster (Mesocricetus auratus), and prairie vole (Microtus ochrogaster). The neural circuits of rodent aggression have been gradually elucidated by several techniques, e.g., immunohistochemistry of immediate-early gene (c-Fos) expression, intracranial drug microinjection, in vivo microdialysis, and optogenetics techniques. Also, evidence accumulated from the analysis of gene-knockout mice shows the involvement of several genes in aggression. Here, we review the brain circuits that have been implicated in aggression, such as the hypothalamus, prefrontal cortex (PFC), dorsal raphe nucleus (DRN), nucleus accumbens (NAc), and olfactory system. We then discuss the roles of glutamate and γ-aminobutyric acid (GABA), excitatory and inhibitory amino acids in the brain, as well as their receptors, in controlling aggressive behavior, focusing mainly on recent findings. At the end of this chapter, we discuss how genes can be identified that underlie individual

  2. Discovery of Novel Alphacoronaviruses in European Rodents and Shrews

    Directory of Open Access Journals (Sweden)

    Theocharis Tsoleridis

    2016-03-01

    Full Text Available Eight hundred and thirteen European rodents and shrews encompassing seven different species were screened for alphacoronaviruses using PCR detection. Novel alphacoronaviruses were detected in the species Rattus norvegicus, Microtus agrestis, Sorex araneus and Myodes glareolus. These, together with the recently described Lucheng virus found in China, form a distinct rodent/shrew-specific clade within the coronavirus phylogeny. Across a highly conserved region of the viral polymerase gene, the new members of this clade were up to 22% dissimilar at the nucleotide level to the previously described Lucheng virus. As such they might represent distinct species of alphacoronaviruses. These data greatly extend our knowledge of wildlife reservoirs of alphacoronaviruses.

  3. Preliminary report of shrews and rodents in and around Lake ...

    African Journals Online (AJOL)

    Surveys during October 2004 and July 2005, in and around Lake Bogoria National Reserve, Kenya, collected evidence of nine rodent species, and one species of shrew. The diversity of small mammals live-trapped within a single habitat type was low compared to similar studies in Africa. The low diversity may be due to the ...

  4. Identification of collected ectoparasites of rodents in the west of Khuzestan Province (Ahvaz and Hovizeh, southwest of Iran

    Directory of Open Access Journals (Sweden)

    Mahmood Rahdar

    2015-08-01

    Full Text Available Objective: To determine possible parasitic arthropods fauna in certain rodent species in the west of Khuzestan Province including Ahvaz and its suburb and suburb of Hovizeh, southwest of Iran. Methods: In the current study Sherman live traps were used to catch the rodents. The rodents were identified using Iranian keys of rodents. The ectoparasites were picked up in different ways from bodies of the anesthetized rodents and stored in 70% ethanol to preserve and identified using international keys. Results: In the present study 3 species and 4 genera of ectoparasites and 4 species of rodents were identified. Conclusions: It is important to explain that the great ectoparasite biodiversity in the west of Khuzestan, with small sampling of rodents, described a high risk factor to transmit the different infectious diseases among domestic animals and humans.

  5. A study of ectoparasites in wild rodents of the Jaz Murian area in the southeast of Iran

    Directory of Open Access Journals (Sweden)

    Asghar Khajeh

    2017-07-01

    Full Text Available Objective: To detect wild rodents ectoparasites in the southeast of Iran. Methods: In this survey, the wild rodents were trapped from 2014 to 2015. The captured rodents were checked for any ectoparasites. Results: In this study, 681 ectoparasites belonged to 6 species of flea, 2 species of lice, 1 species of mite and 2 species of hard tick were collected. The flea species were including, Xenopsylla gerbilli, Xenopsylla cheopis, Xenopsylla buxtoni, Xenopsylla conformis, Nosopsyllus medus and Amphipysylla spp., the lice species were including Hoplopleura spp. and Polyplax spp., the mite species was Ornithonyssus bacoti and tick species were Rhipicephalus spp. and Hyalomma spp. Conclusions: Among all ectoparasites, Hoplopleura spp. and Amphipysylla spp. had the high and low frequency infestation in rodents, respectively. Also among captured rodents, the highest ectoparasites infestation was found in Tatera indica and no ectoparasites in Apodemus witherbyi, Cricetelus migratorius, and Microtus mystacinus kermanesis.

  6. Research Note. Occurrence of gastrointestinal helminths in commensal rodents from Tabasco, Mexico

    OpenAIRE

    Cigarroa-Toledo N.; Santos-Martinez Y. De Los; Zaragoza-Vera C. V.; Garcia-Rodriguez M. M.; Baak-Baak C. M.; Machain-Williams C.; Garcia-Rejon J. E.; Panti-May J. A.; Torres-Chable O. M.

    2017-01-01

    The aim of this study was to determine the prevalence and species composition of helminths in commensal rodents captured inside private residences in the city of Villahermosa in Tabasco, Mexico. Trapping was performed at each house for three consecutive nights from October to December 2015. Fifty commensal rodents were captured: 23 Rattus norvegicus, 16 Mus musculus and 11 Rattus rattus. Rodents were transported alive to the laboratory and held in cages until they defecated. Feces were analyz...

  7. The rodent ultrasound production mechanism.

    Science.gov (United States)

    Roberts, L H

    1975-03-01

    Rodents produce two types of sounds, audible and ultrasonic, that differ markedly in physical structure. Studies of sound production in light gases show that whereas the audible cries appear to be produced, as in the case of most other mammals, by vibrating structures in the larynx, the ultrasonic cries are produced by a different mechanism, probably a whistle. 'Bird-call' whistles are shown to have all the properties of rodent ultrasonic cries and to mimic them in almost every detail. Thus it is concluded that rodents have two distinct sound production mechanisms, one for audible cries and one for ultrasonic cries.

  8. Ectoparasites of Rodents Captured in Hamedan, Western Iran

    Directory of Open Access Journals (Sweden)

    Hamid Zendehfili

    2015-10-01

    Full Text Available Background: Rodents with a population greater than the entire population of other mammals on earth are the source of economic losses and health conflicts. One of the major health problems with the rodents is their role as reservoir hosts of zoonotic diseases. The aim of this study was to assess the infestation of commensal rodents with ectoparasites in Hamedan City, Western Iran.Methods: The samples were collected by live traps during years 2012–2013. After transferring the samples to the Entomological Laboratory of Hamedan University of Medical Sciences, their ectoparasites were collected andidentified.Results: A total of 171 slides were prepared from 105 captured commensal rodents: Mus musculus, Rattus rattus and R. norvegicus comprising three orders namely Mesostigmata: Hypoaspis (Laelaspis astronomica, Dermanyssius sp, Pachylaelapidae (male. Metastigmata: Rhipicephalus sp and Anoplura: Polyplax spinulosa were recovered in Hamedan City. Seventy (66.6% rodents were found infested with at least one species of ectoparasites.Conclusion: The results of our study indicate that ectoparasites infestation in commensal rodents of Hamedan city is high and more attention by local health authorities is needed to prevent zoonotic diseases.

  9. Virtual reality systems for rodents.

    Science.gov (United States)

    Thurley, Kay; Ayaz, Aslı

    2017-02-01

    Over the last decade virtual reality (VR) setups for rodents have been developed and utilized to investigate the neural foundations of behavior. Such VR systems became very popular since they allow the use of state-of-the-art techniques to measure neural activity in behaving rodents that cannot be easily used with classical behavior setups. Here, we provide an overview of rodent VR technologies and review recent results from related research. We discuss commonalities and differences as well as merits and issues of different approaches. A special focus is given to experimental (behavioral) paradigms in use. Finally we comment on possible use cases that may further exploit the potential of VR in rodent research and hence inspire future studies.

  10. A Field Study of Plague and Tularemia in Rodents, Western Iran.

    Science.gov (United States)

    Mostafavi, Ehsan; Shahraki, Abdolrazagh Hashemi; Japoni-Nejad, Alireza; Esmaeili, Saber; Darvish, Jamshid; Sedaghat, Mohammad Mehdi; Mohammadi, Ali; Mohammadi, Zeinolabedin; Mahmoudi, Ahmad; Pourhossein, Behzad; Ghasemi, Ahmad; Gyuranecz, Miklós; Carniel, Elisabeth

    2017-04-01

    Kurdistan Province in Iran is a historical focus for plague and tularemia. This study aimed at assessing the current status of these two foci by studying their rodent reservoirs. Rodents were trapped and their ectoparasites were collected. The genus and species of both rodents and ectoparasites were determined. Serological analyses of rodent blood samples were done by enzyme-linked immunosorbent assay for plague and by standard tube agglutination assay for tularemia. Rodent spleen samples were subjected to bacterial culture, microscopic examination, and real-time PCR to search for active plague or tularemia infection. During this study, 245 rodents were trapped, of which the most abundant genera were Apodemus (40%), Mus (24.49%), and Meriones (12.65%). One hundred fifty-three fleas, 37 mites, and 54 ticks were collected on these rodents. The results of all direct and indirect tests were negative for plague. Serological tests were positive for tularemia in 4.8% of trapped rodents. This study is the first report on the presence of tularemia infection in rodents in Western Iran. Since Meriones persicus is a known reservoir for plague and tularemia, and this rodent carried plague and tularemia vectors in Marivan and Sanandaj districts, there is a real potential for the occurrence of these two diseases in this region.

  11. A comparison of bats and rodents as reservoirs of zoonotic viruses: are bats special?

    Science.gov (United States)

    Luis, Angela D.; Hayman, David T.S.; O'Shea, Thomas J.; Cryan, Paul M.; Gilbert, Amy T.; Pulliam, Juliet R.C.; Mills, James N.; Timonin, Mary E.; Willis, Craig K.R.; Cunningham, Andrew A.; Fooks, Anthony R.; Rupprecht, Charles E.; Wood, James L.N.; Webb, Colleen T.

    2013-01-01

    Bats are the natural reservoirs of a number of high-impact viral zoonoses. We present a quantitative analysis to address the hypothesis that bats are unique in their propensity to host zoonotic viruses based on a comparison with rodents, another important host order. We found that bats indeed host more zoonotic viruses per species than rodents, and we identified life-history and ecological factors that promote zoonotic viral richness. More zoonotic viruses are hosted by species whose distributions overlap with a greater number of other species in the same taxonomic order (sympatry). Specifically in bats, there was evidence for increased zoonotic viral richness in species with smaller litters (one young), greater longevity and more litters per year. Furthermore, our results point to a new hypothesis to explain in part why bats host more zoonotic viruses per species: the stronger effect of sympatry in bats and more viruses shared between bat species suggests that interspecific transmission is more prevalent among bats than among rodents. Although bats host more zoonotic viruses per species, the total number of zoonotic viruses identified in bats (61) was lower than in rodents (68), a result of there being approximately twice the number of rodent species as bat species. Therefore, rodents should still be a serious concern as reservoirs of emerging viruses. These findings shed light on disease emergence and perpetuation mechanisms and may help lead to a predictive framework for identifying future emerging infectious virus reservoirs.

  12. A comparison of bats and rodents as reservoirs of zoonotic viruses: are bats special?

    Science.gov (United States)

    Luis, Angela D.; Hayman, David T. S.; O'Shea, Thomas J.; Cryan, Paul M.; Gilbert, Amy T.; Pulliam, Juliet R. C.; Mills, James N.; Timonin, Mary E.; Willis, Craig K. R.; Cunningham, Andrew A.; Fooks, Anthony R.; Rupprecht, Charles E.; Wood, James L. N.; Webb, Colleen T.

    2013-01-01

    Bats are the natural reservoirs of a number of high-impact viral zoonoses. We present a quantitative analysis to address the hypothesis that bats are unique in their propensity to host zoonotic viruses based on a comparison with rodents, another important host order. We found that bats indeed host more zoonotic viruses per species than rodents, and we identified life-history and ecological factors that promote zoonotic viral richness. More zoonotic viruses are hosted by species whose distributions overlap with a greater number of other species in the same taxonomic order (sympatry). Specifically in bats, there was evidence for increased zoonotic viral richness in species with smaller litters (one young), greater longevity and more litters per year. Furthermore, our results point to a new hypothesis to explain in part why bats host more zoonotic viruses per species: the stronger effect of sympatry in bats and more viruses shared between bat species suggests that interspecific transmission is more prevalent among bats than among rodents. Although bats host more zoonotic viruses per species, the total number of zoonotic viruses identified in bats (61) was lower than in rodents (68), a result of there being approximately twice the number of rodent species as bat species. Therefore, rodents should still be a serious concern as reservoirs of emerging viruses. These findings shed light on disease emergence and perpetuation mechanisms and may help lead to a predictive framework for identifying future emerging infectious virus reservoirs. PMID:23378666

  13. Thieving rodents as substitute dispersers of megafaunal seeds

    Science.gov (United States)

    Jansen, Patrick A.; Hirsch, Ben T.; Emsens, Willem-Jan; Zamora-Gutierrez, Veronica; Wikelski, Martin; Kays, Roland

    2012-01-01

    The Neotropics have many plant species that seem to be adapted for seed dispersal by megafauna that went extinct in the late Pleistocene. Given the crucial importance of seed dispersal for plant persistence, it remains a mystery how these plants have survived more than 10,000 y without their mutualist dispersers. Here we present support for the hypothesis that secondary seed dispersal by scatter-hoarding rodents has facilitated the persistence of these large-seeded species. We used miniature radio transmitters to track the dispersal of reputedly megafaunal seeds by Central American agoutis, which scatter-hoard seeds in shallow caches in the soil throughout the forest. We found that seeds were initially cached at mostly short distances and then quickly dug up again. However, rather than eating the recovered seeds, agoutis continued to move and recache the seeds, up to 36 times. Agoutis dispersed an estimated 35% of seeds for >100 m. An estimated 14% of the cached seeds survived to the next year, when a new fruit crop became available to the rodents. Serial video-monitoring of cached seeds revealed that the stepwise dispersal was caused by agoutis repeatedly stealing and recaching each other’s buried seeds. Although previous studies suggest that rodents are poor dispersers, we demonstrate that communities of rodents can in fact provide highly effective long-distance seed dispersal. Our findings suggest that thieving scatter-hoarding rodents could substitute for extinct megafaunal seed dispersers of tropical large-seeded trees. PMID:22802644

  14. The role of rodents in the ecology of Ixodes ricinus and associated pathogens in Central and Eastern Europe.

    Science.gov (United States)

    Mihalca, Andrei D; Sándor, Attila D

    2013-01-01

    Rodents comprise more species than any other mammal order. Most rodents are considered keystone species in their ecological communities, hence the survival of many other species in the ecosystem depend on them. From medical point of view, this is particularly important for rodent-dependent pathogens. In the particular case of tick-borne diseases, rodents are important as hosts for vector ticks and as reservoir hosts (Lyme borreliosis, human granulocytic anaplasmosis, Crimean-Congo hemorrhagic fever, Tick-borne relapsing fevers, tick-borne rickettsioses, babesiosis). Community and population ecology of rodents was shown to be correlated with disease ecology in the case of many tick-borne diseases. In Eastern Europe, several adult hard-tick species use rodents as their principal hosts: Ixodes apronophorus, I. crenulatus, I. laguri, I. redikorzevi, I. trianguliceps. However, the majority of ticks feeding on rodents are immature stages of ticks which as adults are parasitic on larger mammals. Larvae and nymphs of Ixodes ricinus, the most abundant and medically important tick from Europe, are commonly found on rodents. This is particularly important, as many rodents are synanthropic and, together with other micromammals and birds are often the only available natural hosts for ticks in urban environments. This work reviews the correlated ecology of rodents and I. ricinus.

  15. Blood protozoan parasites of rodents in Jos, Plateau State, Nigerai ...

    African Journals Online (AJOL)

    One hundred and thirty rodents, comprising nine different species caught from seven different locations in Jos, Nigeria, were examined for blood protozoan parasites, and 82(63.08%) were positive, with Plasmodium 63(48.46%), Trypanosoma 4(3.08%), Toxoplasma 6(4.62%), Babesia 7(5.38%) and Anaplasma 2(1.54%).

  16. Multiple infections of rodents with zoonotic pathogens in Austria.

    Science.gov (United States)

    Schmidt, Sabrina; Essbauer, Sandra S; Mayer-Scholl, Anne; Poppert, Sven; Schmidt-Chanasit, Jonas; Klempa, Boris; Henning, Klaus; Schares, Gereon; Groschup, Martin H; Spitzenberger, Friederike; Richter, Dania; Heckel, Gerald; Ulrich, Rainer G

    2014-07-01

    Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host-pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans.

  17. Stress, social behavior, and resilience: Insights from rodents

    Science.gov (United States)

    Beery, Annaliese K.; Kaufer, Daniela

    2014-01-01

    The neurobiology of stress and the neurobiology of social behavior are deeply intertwined. The social environment interacts with stress on almost every front: social interactions can be potent stressors; they can buffer the response to an external stressor; and social behavior often changes in response to stressful life experience. This review explores mechanistic and behavioral links between stress, anxiety, resilience, and social behavior in rodents, with particular attention to different social contexts. We consider variation between several different rodent species and make connections to research on humans and non-human primates. PMID:25562050

  18. Hubungan Kecanduan Bermain Video Games Kekerasan dengan Perilaku Agresif pada Murid Laki-laki Kelas IV dan V di SD Negeri 02 Cupak Tangah Pauh Kota Padang

    Directory of Open Access Journals (Sweden)

    Rivo Armanda Satria

    2015-01-01

    Full Text Available AbstrakPerilaku agresif adalah perilaku yang bertujuan untuk menyakiti orang lain, untuk mengekspresikan perasaan negatifnya seperti permusuhan untuk mencapai tujuan yang diinginkan. Terdapat 4 aspek agresivitas, yaitu kemarahan, permusuhan, agresi verbal, dan agresi fisik. Salah satu faktor yang diduga mempengaruhi perilaku agresif adalah kebiasaan bermain video games yang mengandung unsur kekerasan. Tujuan penelitian ini adalah untuk mengetahui hubungan perilaku kecanduan bermain video games yang mengandung unsur kekerasan terhadap prilaku agresif pada murid laki-laki kelas IV dan V di SD Negeri 02 Cupak Tangah Pauh Kota Padang Tahun 2014. Penelitian ini menggunakan disain cross sectional study dengan jumlah sampel sebanyak 83 orang murid laki-laki dari kelas IV dan V di SD N 02 Cupak Tangah Pauh. Data dikumpulkan melalui wawancara kepada responden menggunakan kuesioner yang kemudian di analisis dengan uji statistik chi-square dengan derajat kepercayaan 95% (0,05.Hasil penelitian menunjukkan persentase responden yang memiliki perilaku agresif lebih tinggi pada responden yang mengalami kecanduan bermain video games yang mengandung unsur kekerasan jika dibandingkan dengan responden yang tidak mengalami kecanduan bermain video games yang mengandung unsur kekerasan (67,6%:20,4% dan terdapat hubungan yang bermakna antara kecanduan bermain video games yang mengandung unsur kekerasan dengan perilaku agresif (p-value=0,000.Disarankan bagi pihak sekolah agar memiliki program konseling psikologis anak misalnya dalam bentuk UKESWA (usaha kesehatan jiwa yang termasuk dalam program UKS (usaha kesehatan sekolah untuk mendeteksi sejak dini perilaku kecanduan anak terhadap video games yang mengandung unsur kekerasan dan perilaku agresif anak sehingga dapat diberikan bimbingan untuk mengatasi kecanduan dan perilaku agresif tersebut agar tidak berlanjut dan menjadi conduct disorder atau perilaku anti sosialKata kunci : agresif, kecanduan, video games

  19. Multiplex PCR identification of Taenia spp. in rodents and carnivores.

    Science.gov (United States)

    Al-Sabi, Mohammad N S; Kapel, Christian M O

    2011-11-01

    The genus Taenia includes several species of veterinary and public health importance, but diagnosis of the etiological agent in definitive and intermediate hosts often relies on labor intensive and few specific morphometric criteria, especially in immature worms and underdeveloped metacestodes. In the present study, a multiplex PCR, based on five primers targeting the 18S rDNA and ITS2 sequences, produced a species-specific banding patterns for a range of Taenia spp. Species typing by the multiplex PCR was compared to morphological identification and sequencing of cox1 and/or 12S rDNA genes. As compared to sequencing, the multiplex PCR identified 31 of 32 Taenia metacestodes from rodents, whereas only 14 cysts were specifically identified by morphology. Likewise, the multiplex PCR identified 108 of 130 adult worms, while only 57 were identified to species by morphology. The tested multiplex PCR system may potentially be used for studies of Taenia spp. transmitted between rodents and carnivores.

  20. Gut morpbology of tbe Otomyine rodents: an arid-mesic comparison

    African Journals Online (AJOL)

    1998-06-15

    Jun 15, 1998 ... Despite the broad similarity in the gross gastro-intestinal anatomy between the speCies ... Present address: Department of Physiology, University of the Western ..... on growth and renal performance of juvenile Namib rodents.

  1. Synanthropic rodents as possible reservoirs of shigatoxigenic Escherichia coli strains

    Directory of Open Access Journals (Sweden)

    Ximena eBlanco Crivelli

    2012-11-01

    Full Text Available Shigatoxigenic Escherichia coli (STEC strains are worldwide zoonotic pathogen responsible for different cases of human disease including hemolytic uremic syndrome (HUS. Transmission of STEC to humans occurs through the consumption of food and water contaminated by faeces of carriers and by person-to-person contact.The objective of this study was twofold: (a to investigate whether synanthropic rodents are possible reservoirs of STEC in the urban area and (b whether a particular genus out of synanthropic rodent is the principal carrier of STEC.One hundred forty-five rodents were captured in Buenos Aires City. Screening for stx1/stx2 and rfbO157 was done by PCR from the confluence zone. STEC isolates were further characterized with biochemical tests by standard methods. Additional virulence factors (eae, ehxA and saa were also determined by PCR. Forty-one of the rodents were necropsied and sample of kidney and small and large intestine were taken for histopathological diagnosis. The samples sections were stained with hematoxylin-eosin, and observed by light microscopy to evaluate the systemic involvement of these species in natural infections. STEC was isolated from seven out of twenty seven suspect animals at screening. The following genotypes were found in the STEC strains: stx1/stx2/ehxA (1, stx2 (4, stx2/ehxA (1, stx2/ehxA/eae (1. Neither gross nor microscopic lesions compatible with those produced by Shiga toxin were observed in the studied organs of necropsied rodents.The bivariate analysis including the hundred forty-five rodents data showed that the isolation of STEC is associated positively to Rattus genus. This synanthropic species may play a role in the transmissibility of the agent thus being a risk to the susceptible population. Their control should be included specifically in actions to dismiss the contamination of food and water by STEC in the urban area, as additional strategies for epidemiological control.

  2. Forecasting rodent outbreaks in Africa

    DEFF Research Database (Denmark)

    Leirs, Herwig; Verhagen, Ron; Verheyen, Walter

    1996-01-01

    1. Rainfall data were collated for years preceding historical outbreaks of Mastomys rats in East Africa in order to test the hypothesis that such outbreaks occur after long dry periods. 2. Rodent outbreaks were generally not preceded by long dry periods. 3. Population dynamics of Mastomys...... natalensis rats in Tanzania are significantly affected by the distribution of rainfall during the rainy season. 4. All previous rodent outbreaks in Tanzania were preceded by abundant rainfall early in the rainy season, i.e, towards the end of the year. 5. A flow chart is constructed to assess the likelihood...

  3. Farmer survey in the hinterland of Kisangani (Democratic Republic of Congo) on rodent crop damage and rodent control techniques used

    DEFF Research Database (Denmark)

    Drazo, Nicaise Amundala; Kennis, Jan; Leirs, Herwig

    2008-01-01

    We conducted a survey on rodent crop damage among farmers in the hinterland of Kisangani (Democratic Republic of Congo). We studied the amount of crop damage, the rodent groups causing crop damage, the growth stages affected and the control techniques used. We conducted this survey in three...... municipalities using a standard questionnaire form translated into local languages, between November 2005 and June 2006 and during July 2007. We used the Quotas method and interviewed 70 households per municipality. Farmers indicated rodent groups implicated in crop damage on color photographs. Two types...... of survey techniques were used: individual and focus-group surveys. The sugar cane rat, Thryonomys sp. and Lemniscomys striatus caused most damage to crops, but inside granaries, Rattus rattus was the primary pest species eating stored food supplies and causing damage to stored goods. Cassava and maize were...

  4. Correlates of Recent Declines of Rodents in Northern and Southern Australia: Habitat Structure Is Critical.

    Directory of Open Access Journals (Sweden)

    Michael J Lawes

    Full Text Available Australia has experienced dramatic declines and extinctions of its native rodent species over the last 200 years, particularly in southern Australia. In the tropical savanna of northern Australia significant declines have occurred only in recent decades. The later onset of these declines suggests that the causes may differ from earlier declines in the south. We examine potential regional effects (northern versus southern Australia on biological and ecological correlates of range decline in Australian rodents. We demonstrate that rodent declines have been greater in the south than in the tropical north, are strongly influenced by phylogeny, and are consistently greater for species inhabiting relatively open or sparsely vegetated habitat. Unlike in marsupials, where some species have much larger body size than rodents, body mass was not an important predictor of decline in rodents. All Australian rodent species are within the prey-size range of cats (throughout the continent and red foxes (in the south. Contrary to the hypothesis that mammal declines are related directly to ecosystem productivity (annual rainfall, our results are consistent with the hypothesis that disturbances such as fire and grazing, which occur in non-rainforest habitats and remove cover used by rodents for shelter, nesting and foraging, increase predation risk. We agree with calls to introduce conservation management that limits the size and intensity of fires, increases fire patchiness and reduces grazing impacts at ecological scales appropriate for rodents. Controlling feral predators, even creating predator-free reserves in relatively sparsely-vegetated habitats, is urgently required to ensure the survival of rodent species, particularly in northern Australia where declines are not yet as severe as those in the south.

  5. Toxoplasma gondii antibodies in wild rodents and marsupials from the Atlantic Forest, state of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Solange Maria Gennari

    Full Text Available Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and marsupials play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 48 marsupials, captured in the Atlantic Forest, São Paulo State, southeastern Brazil, were analyzed for the presence of T. gondii antibodies. Antibodies detected by the modified agglutination test (MAT ≥ 25 were found in 8.6% (13/151 of the rodents and 10.4% (5/48 of the marsupials, with titers ranging from 25 to 6400 and from 25 to 3200, respectively for the rodents and marsupials. Three of the eight species of rodents (Akodon spp., Oligoryzomys nigripesand Rattus norvegicus, and one from the four marsupial species (Didelphis aurita presented positive animals. T. gondii was described for the first time in the rodent Oligoryzomys nigripes.

  6. Guide to Commensal Rodent Control

    Science.gov (United States)

    1991-12-01

    in many detergents also fluoresce. For positive identification, place the suspect material on Urease Siom lhymol Blue test paper, moisten with water...are applied in a thin layer in protected rat and mouse r’unways, baitboxes, or tubes along walls. The powder is picked up by the rodents on their feet

  7. The Ethics of Rodent Control

    NARCIS (Netherlands)

    Meerburg, B.G.; Brom, F.W.A.; Kijlstra, A.

    2008-01-01

    Because western societies generally see animals as objects of moral concern, demands have been made on the way they are treated, e.g. during animal experimentation. In the case of rodent pests, however, inhumane control methods are often applied. This inconsistency in the human-animal relationship

  8. A biometric approach to laboratory rodent identification.

    Science.gov (United States)

    Cameron, Jens; Jacobson, Christina; Nilsson, Kenneth; Rögnvaldsson, Thorsteinn

    2007-03-01

    Individual identification of laboratory rodents typically involves invasive methods, such as tattoos, ear clips, and implanted transponders. Beyond the ethical dilemmas they may present, these methods may cause pain or distress that confounds research results. The authors describe a prototype device for biometric identification of laboratory rodents that would allow researchers to identify rodents without the complications of other methods. The device, which uses the rodent's ear blood vessel pattern as the identifier, is fast, automatic, noninvasive, and painless.

  9. Verification of natural infection of peridomestic rodents by PCV2 on commercial swine farms.

    Science.gov (United States)

    Pinheiro, Albanno Leonard Braz Campos; Bulos, Luiz Henrique Silva; Onofre, Thiago Souza; de Paula Gabardo, Michelle; de Carvalho, Otávio Valério; Fausto, Mariana Costa; Guedes, Roberto Maurício Carvalho; de Almeida, Márcia Rogéria; Silva Júnior, Abelardo

    2013-06-01

    The porcine circovirus-2 (PCV2) is the main agent responsible for porcine circovirus associated diseases (PCVAD). Few studies have been done regarding PCV2 infection in other species. The purpose of this study was to investigate the occurrence of PCV2 infection in the peridomestic rodent species Mus musculus and Rattus rattus on commercial pig farms in Brazil. Immunohistochemistry assay demonstrated PCV2 in the spleen, lung and kidney. Viral DNA was detected in tissues by nested PCR assay. Partial sequences of PCV2 genomes detected in the rodents had strong identity with gene sequences of PCV2 isolates from pigs. These results show that the studied peridomestic rodent species can be naturally infected by PCV2. However, further studies are needed to confirm PCV2 transmission from rodents to pigs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Population response of rodents to control with rodenticides

    Directory of Open Access Journals (Sweden)

    A.V. TCHABOVSKY

    2009-04-01

    Full Text Available We summarize theoretical approaches and practice of rodent pest control in Russia and former USSR during last 50 years. We review literature as well as original data to understand mechanisms of rodent populations recovery after chemical control campaigns in urban areas, agricultural lands and natural foci of plague. Laboratory and field experiments indicate that inherent individual variation in behavioural, physiological and life-history traits provides survival of heterogeneous mix of individuals in residual population with increased resistance to poisonous baits and high reproductive potential that leads to fast recovery of a population. In a series of field experiments with various rodent and lagomorph species (Mus musculus, Rattus norvegicus, Meriones unguiculatus, M.meridianus, M.tamariscinus, Ochotona pallasii we have shown that patterns of recolonization of depopulated area and mechanisms of population recovery vary among species and depend on species-specific social organization. After control territorial and group-living species demonstrated an increase in mobility and affiliative and marking behaviour and a decrease in intraspecific aggression. The rate of recolonization of treated areas was high due to redistribution of survived individuals and immigration by neighbors. Population recovered to original level due to increased breeding performance and fecundity of both survived residents and immigrants. In contrast, socially-independent species exhibited minor changes in behaviour. Recolonization was mainly due to better survival and recruitment of youngs, so the rate of recolonization was low. Species-specificity of behavioural compensation mechanisms to control should be considered when developing ecologically based rodent management strategies.

  11. 21 CFR 1250.96 - Rodent control.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rodent control. 1250.96 Section 1250.96 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be... of rodent control. ...

  12. Occurrence of ectoparasitic arthropods associated with rodents in Hail region northern Saudi Arabia.

    Science.gov (United States)

    Asiry, Khalid A; Fetoh, Badr El-Sabah A

    2014-09-01

    Ectoparasitic arthropods are a diverse element of the Saudi fauna. Due to this, a survey of ectoparasites associated with rodents was conducted as a preliminary study in five districts of Hail region of northern Saudi Arabia for the first time. Ectoparasites extracted from 750 rodents were sampled and identified by recording their frequency of appearance. Results revealed that 1,287 ectoparasites infested 316 of the captured rodent hosts. These ectoparasites parasitized on four species of rodents including three species of rats Rattus rattus rattus, Rattus rattus frugivorus, and Rattus rattus alexandrinus and one species of mouse Acomys dimidiatus (Rodentia: Muridae). The ectoparasites belong to four different groups: ticks, fleas, lice, and mites. Ticks were the highest in the number, while fleas were the lowest among all the extracted ectoparasite groups. The collected ectoparasitic arthropods consisted of seven species. Ticks were of two species: Rhipicephalus turanicus and Rhipicephalus sanguineus (Acari: Ixodidae), fleas were of two species: Xenopsylla cheopis and Xenopsyllus conformis mycerini (Siphonaptera: Pulicidae), lice was a single species: Polyplax serrata (Anoplura: Hoplopleuridae), and mites were of two species: Laelaps nuttali and Laelaps echidninus (Mesostigmata: Laelapidae). The findings of the study showed that the intensity of infestation was varied between rodent host sexes, wherein females had the highest rate of parasitic infestation, and the parasitic index of appearance was very high for one group of parasites (i.e., ticks). The parasitic prevalence was 42.13 % on rodents, and mites were the most prevalent parasite species. Overall, this study was carried out to establish baseline data for ectoparasite-infested rodents in Hail region, Saudi Arabia, and may help for appropriate planning to control zoonotic diseases in this area.

  13. A higher-taxon approach to rodent conservation priorities for the 21st century

    Directory of Open Access Journals (Sweden)

    Amori, G.

    2003-12-01

    Full Text Available Although rodents are not considered among the most threatened mammals, there is ample historical evidence concerning the vulnerability to extinction of several rodent phylogenetic lineages. Owing to the high number of species, poor taxonomy and the lack of detailed information on population status, the assessment of threat status according to IUCN criteria has still to be considered arbitrary in some cases. Public appreciation is scarce and tends to overlook the ecological role and conservation problems of an order representing about 41 percent of mammalian species. We provide an overview of the most relevant information concerning the conservation status of rodents at the genus, subfamily, and family level. For species¿poor taxa, the importance of distinct populations is highlighted and a splitter approach in taxonomy is adopted. Considering present constraints, strategies for the conservation of rodent diversity must rely mainly on higher taxon and hot-spot approaches. A clear understanding of phyletic relationships among difficult groups -such as Rattus, for instance- is an urgent goal. Even if rodent taxonomy is still unstable, high taxon approach is amply justified from a conservation standpoint as it offers a more subtle overview of the world terrestrial biodiversity than that offered by large mammals. Of the circa 451 living rodent genera, 126 (27,9 %, representing 168 living species, deserve conservation attention according to the present study. About 76 % of genera at risk are monotypic, confirming the danger of losing a considerable amount of phylogenetic distinctiveness.

  14. Research Note. Occurrence of gastrointestinal helminths in commensal rodents from Tabasco, Mexico

    Directory of Open Access Journals (Sweden)

    Cigarroa-Toledo N.

    2017-06-01

    Full Text Available The aim of this study was to determine the prevalence and species composition of helminths in commensal rodents captured inside private residences in the city of Villahermosa in Tabasco, Mexico. Trapping was performed at each house for three consecutive nights from October to December 2015. Fifty commensal rodents were captured: 23 Rattus norvegicus, 16 Mus musculus and 11 Rattus rattus. Rodents were transported alive to the laboratory and held in cages until they defecated. Feces were analyzed for helminth eggs using the Sheather’s flotation technique. The overall prevalence of helminths in rodents was 60 %: R. norvegicus was more likely to be parasitized (87.0 % than R. rattus (63.6 % and M. musculus (18.8 %. Eggs from at least 13 species of helminths were identified: Hymenolepis diminuta, Rodentolepis nana, Moniliformis moniliformis, Heligmosomoides polygyrus, Heterakis spumosa, Mastophorus muris, Nippostrongylus brasiliensis, Strongyloides ratti, Syphacia obvelata, Syphacia muris, Toxocara sp., Trichosomoides crassicauda, and Trichuris muris. This is the first study to report the presence of H. polygyrus, S. ratti and T. crassicauda in commensal rodents in Mexico. In conclusion, our results suggest that helminths commonly infect commensal rodents in Villahermosa and therefore rodents present a health risk to inhabitants in this region.

  15. Sleep in the Cape Mole Rat: A Short-Sleeping Subterranean Rodent.

    Science.gov (United States)

    Kruger, Jean-Leigh; Gravett, Nadine; Bhagwandin, Adhil; Bennett, Nigel C; Archer, Elizabeth K; Manger, Paul R

    2016-01-01

    The Cape mole rat Georychus capensis is a solitary subterranean rodent found in the western and southern Cape of South Africa. This approximately 200-gram bathyergid rodent shows a nocturnal circadian rhythm, but sleep in this species is yet to be investigated. Using telemetric recordings of the electroencephalogram (EEG) and electromyogram (EMG) in conjunction with video recordings, we were able to show that the Cape mole rat, like all other rodents, has sleep periods composed of both rapid eye movement (REM) and slow-wave (non-REM) sleep. These mole rats spent on average 15.4 h awake, 7.1 h in non-REM sleep and 1.5 h in REM sleep each day. Cape mole rats sleep substantially less than other similarly sized terrestrial rodents but have a similar percentage of total sleep time occupied by REM sleep. In addition, the duration of both non-REM and REM sleep episodes was markedly shorter in the Cape mole rat than has been observed in terrestrial rodents. Interestingly, these features (total sleep time and episode duration) are similar to those observed in another subterranean bathyergid mole rat, i.e. Fukomys mechowii. Thus, there appears to be a bathyergid type of sleep amongst the rodents that may be related to their environment and the effect of this on their circadian rhythm. Investigating further species of bathyergid mole rats may fully define the emerging picture of sleep in these subterranean African rodents. © 2016 S. Karger AG, Basel.

  16. Two new rodent models for actinide toxicity studies

    International Nuclear Information System (INIS)

    Taylor, G.N.; Jones, C.W.; Gardner, P.A.; Lloyd, R.D.; Mays, C.W.; Charrier, K.E.

    1981-01-01

    Two small rodent species, the grasshopper mouse (Onychomys leucogaster) and the deer mouse (Peromyscus maniculatus), have tenacious and high retention in the liver and skeleton of plutonium and americium following intraperitoneal injection of Pu and Am in citrate solution. Liver retention of Pu and Am in the grasshopper mouse is higher than liver retention in the deer mouse. Both of these rodents are relatively long-lived, breed well in captivity, and adapt suitably to laboratory conditions. It is suggested that these two species of mice, in which plutonium retention is high and prolonged in both the skeleton and liver, as it is in man, may be useful animal models for actinide toxicity studies

  17. The Need for Speed in Rodent Locomotion Analyses

    OpenAIRE

    Batka, Richard J.; Brown, Todd J.; Mcmillan, Kathryn P.; Meadows, Rena M.; Jones, Kathryn J.; Haulcomb, Melissa M.

    2014-01-01

    Locomotion analysis is now widely used across many animal species to understand the motor defects in disease, functional recovery following neural injury, and the effectiveness of various treatments. More recently, rodent locomotion analysis has become an increasingly popular method in a diverse range of research. Speed is an inseparable aspect of locomotion that is still not fully understood, and its effects are often not properly incorporated while analyzing data. In this hybrid manuscript,...

  18. Transformation of the rodent malaria parasite Plasmodium chabaudi

    OpenAIRE

    Spence, Philip J; Cunningham, Deirdre; Jarra, William; Lawton, Jennifer; Langhorne, Jean; Thompson, Joanne

    2011-01-01

    The rodent malaria parasite Plasmodium chabaudi chabaudi shares many features with human malaria species, including P. falciparum, and is the in vivo model of choice for many aspects of malaria research in the mammalian host, from sequestration of parasitized erythrocytes, to antigenic variation and host immunity and immunopathology. this protocol describes an optimized method for the transformation of mature blood-stage P.c. chabaudi and a description of a vector that targets efficient, sing...

  19. Tick parasites of rodents in Romania: host preferences, community structure and geographical distribution.

    Science.gov (United States)

    Mihalca, Andrei D; Dumitrache, Mirabela O; Sándor, Attila D; Magdaş, Cristian; Oltean, Miruna; Györke, Adriana; Matei, Ioana A; Ionică, Angela; D'Amico, Gianluca; Cozma, Vasile; Gherman, Călin M

    2012-11-21

    Ticks are among the most important vectors of zoonotic diseases in temperate regions of Europe, with widespread distribution and high densities, posing an important medical risk. Most ticks feed on a variety of progressively larger hosts, with a large number of small mammal species typically harbouring primarily the immature stages. However, there are certain Ixodidae that characteristically attack micromammals also during their adult stage. Rodents are widespread hosts of ticks, important vectors and competent reservoirs of tick-borne pathogens. Micromammal-tick associations have been poorly studied in Romania, and our manuscript shows the results of a large scale study on tick infestation epidemiology in rodents from Romania. Rodents were caught using snap-traps in a variety of habitats in Romania, between May 2010 and November 2011. Ticks were individually collected from these rodents and identified to species and development stage. Frequency, mean intensity, prevalence and its 95% confidence intervals were calculated using the EpiInfo 2000 software. A p value of Romania for the presence of ticks. Each collected tick was identified to species level and the following epidemiological parameters were calculated: prevalence, mean intensity and mean abundance. The total number of ticks collected from rodents was 483, with eight species identified: Ixodes ricinus, I. redikorzevi, I. apronophorus, I. trianguliceps, I. laguri, Dermacentor marginatus, Rhipicephalus sanguineus and Haemaphysalis sulcata. The overall prevalence of tick infestation was 29.55%, with a mean intensity of 3.86 and a mean abundance of 1.14. Only two polyspecific infestations were found: I. ricinus + I. redikorzevi and I. ricinus + D. marginatus. Our study showed a relatively high diversity of ticks parasitizing rodents in Romania. The most common tick in rodents was I. ricinus, followed by I. redikorzevi. Certain rodents seem to host a significantly higher number of tick species than others, the

  20. Epidemiological distribution of rodents as potent reservoirs for infectious diseases in the provinces of Mazandaran, Gilan and Golestan, northern Iran

    Directory of Open Access Journals (Sweden)

    Behzad Esfandiari

    2017-05-01

    Full Text Available Rodents are mammals that comprise more than 2000 species and approximately 30 families. There are many morphological and ecological differences among them as variations in their shape, size, weight and habitat. In addition to significant economic losses, rodents have a major role in the dissemination of infectious diseases caused by viruses, bacteria, parasites or other micro-organisms. Rodents are important reservoirs of diseases which have been observed in many cities of Iran provinces especially along Caspian Sea border to Alborz Mountain. The aim of this study is to assess the geographical distribution of rodents in three provinces of northern part of Iran as reservoir of potential endemic infectious diseases. Rodents in 10 major parts of each of the three provinces of Mazandaran, Gilan and Golestan, northern Iran were collected and a total of 404 rodents were trapped alive. They were determined by the key characteristics such as gender, genus, species, different locations and topological situation. Statistical analysis was performed to characterize the study sample and to correlate all variables and parameters. The distribution frequencies of three, five and six genera of rodents were identified in Mazandaran, Gilan and Golestan provinces respectively. The overall distribution frequency of eight genera of rodents in the three provinces were identified as Rattus (R. norvegicus (67.3%, R. rattus (13.6%, Apodemus sylvaticus (13.9%, Arvicola (1%, Mus musculus (0.3%, Nesokia indica (2.5%, Cricetulus migrates (0.7% and Rhombomys opimus (0.7%. The results of this study determined the geographic distribution of the rodents in the three northern provinces of Iran. It is indicated the association of various distribution and diversity of rodents with provincial location. The overall distribution frequency of eight genera of rodents was recognized in the above three provinces geographical locations. This study confirms epidemiological distribution of

  1. The need to implement the landscape of fear within rodent pest management strategies.

    Science.gov (United States)

    Krijger, Inge M; Belmain, Steven R; Singleton, Grant R; Groot Koerkamp, Peter Wg; Meerburg, Bastiaan G

    2017-12-01

    Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically based rodent management (EBRM). An important aspect of EBRM is a strong understanding of rodent pest species ecology, behaviour and spatiotemporal factors. Gaining insight into the behaviour of pest species is a key aspect of EBRM. The landscape of fear (LOF) is a mapping of the spatial variation in the foraging cost arising from the risk of predation, and reflects the levels of fear a prey species perceives at different locations within its home range. In practice, the LOF maps habitat use as a result of perceived fear, which shows where bait or traps are most likely to be encountered and used by rodents. Several studies have linked perceived predation risk of foraging animals with quitting-harvest rates or giving-up densities (GUDs). GUDs have been used to reflect foraging behaviour strategies of predator avoidance, but to our knowledge very few papers have directly used GUDs in relation to pest management strategies. An opportunity for rodent control strategies lies in the integration of the LOF of rodents in EBRM methodologies. Rodent management could be more efficient and effective by concentrating on those areas where rodents perceive the least levels of predation risk. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  2. Indirect effects of rodents on arthropods in a Scandinavian boreal forest

    OpenAIRE

    Malá, Barbora

    2016-01-01

    Rodents in boreal forest are an important component of food webs. Their role as drivers of the boreal forest ecosystem is debated. As herbivores they affect plant communities and alter qualities of plants. Consequently availability of food resources for other herbivorous species is altered. In my thesis I studied whether rodents indirectly influence communities of arthropods via plant resources. It is assumed that phytophagous arthropods respond to changes in plant resources by different feed...

  3. Zoonotic pathogens in Atlantic Forest wild rodents in Brazil: Bartonella and Coxiella infections.

    Science.gov (United States)

    Rozental, Tatiana; Ferreira, Michelle Santos; Guterres, Alexandro; Mares-Guia, Maria Angélica; Teixeira, Bernardo R; Gonçalves, Jonathan; Bonvicino, Cibele Rodrigues; D'Andrea, Paulo Sergio; de Lemos, Elba Regina Sampaio

    2017-04-01

    Zoonotic pathogens comprise a significant and increasing fraction of all emerging and re-emerging infectious diseases that plague humans. Identifying host species is one of the keys to controlling emerging infectious diseases. From March 2007 until April 2012, we collected a total of 131 wild rodents in eight municipalities of Rio de Janeiro, Brazil. We investigated these rodents for infection with Coxiella burnetii, Bartonella spp. and Rickettsia spp. In total, 22.1% (29/131) of the rodents were infected by at least one pathogen; co-infection was detected in 1.5% (2/131) of rodents. Coxiella burnetii was detected in 4.6% (6/131) of the wild animals, 17.6% of the rodents harbored Bartonella spp. No cases of Rickettsia were identified. Bartonella doshiae and Bartonella vinsonii were the species found on the wild mammals. This report is the first to note C. burnetii, B. doshiae and B. vinsonii natural infections in Atlantic Forest wild rodents in Brazil. Our work highlights the potential risk of transmission to humans, since most of the infected specimens belong to generalist species that live near human dwellings. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Prevalence and genetic diversity of Bartonella strains in rodents from northwestern Mexico.

    Science.gov (United States)

    Rubio, André V; Ávila-Flores, Rafael; Osikowicz, Lynn M; Bai, Ying; Suzán, Gerardo; Kosoy, Michael Y

    2014-12-01

    Bartonella infections were investigated in wild rodents from northwestern Chihuahua, Mexico. A total of 489 rodents belonging to 14 species were surveyed in four areas. Bartonella bacteria were cultured from 50.1% of rodent samples (245/489). Infection rates ranged from 0% to 83.3% per rodent species, with no significant difference between sites except for Cynomys ludovicianus. Phylogenetic analyses of the citrate synthase gene (gltA) of the Bartonella isolates revealed 23 genetic variants (15 novel and 8 previously described), clustering into five phylogroups. Three phylogroups were associated with Bartonella vinsonii subsp. vinsonii, B. vinsonii subsp. arupensis, and B. washoensis, respectively. The other two phylogroups were not genetically related to any known Bartonella species. The genetic variants and phylogenetic groups exhibited a high degree of host specificity, mainly at the genus and family levels. This is the first study that describes the genetic diversity of Bartonella strains in wild rodents from Mexico. Considering that some variants found in this study are associated with Bartonella species that have been reported as zoonotic, more investigations are needed to further understand the ecology of Bartonella species in Mexican wildlife and their implications for human health.

  5. Hepatozoon spp. infections in wild rodents in an area of endemic canine hepatozoonosis in southeastern Brazil.

    Science.gov (United States)

    Demoner, Larissa de Castro; Magro, Natalia Mizuhira; da Silva, Maria Regina Lucas; de Paula Antunes, João Marcelo Azevedo; Calabuig, Cecilia Irene Pérez; O'Dwyer, Lucia Helena

    2016-07-01

    Hepatozoon canis is a tick-borne parasite that occurs worldwide. In rural areas of Brazil, H. canis vectors remain unknown, which has led to speculation about alternative routes of transmission. Small rodents can play a role in the transmission (via predation) of Hepatozoon americanum, which led us to question whether predation might be an alternative mode of transmission for H. canis. Thus, this study investigated whether Hepatozoon spp. are present in wild small rodents in forest fragments that surround rural areas in Botucatu County, São Paulo, Brazil, where canine hepatozoonosis is endemic. The study included blood samples from 158 dogs, which were screened by microscopy and molecular analysis. Blood samples and tissues from 67 rodents were obtained for histopathology and molecular detection. The prevalence of H. canis was high (66.45%) in dogs from rural areas of Botucatu, São Paulo, Brazil. The molecular analysis showed that wild rodent species in Brazil were infected with Hepatozoon spp. other than H. canis. Therefore, although the hypothesis that sylvatic rodents act as reservoirs for H. canis was not supported, the presence of monozoic cysts in the rodents suggests that, in addition to intermediate hosts, wild small rodents in Brazil might act as paratenic hosts of Hepatozoon spp. because they harbor infective stages for intermediate host predators. Copyright © 2016 Elsevier GmbH. All rights reserved.

  6. Domestic cats and dogs create a landscape of fear for pest rodents around rural homesteads.

    Directory of Open Access Journals (Sweden)

    Themb'alilahlwa A M Mahlaba

    Full Text Available Using domestic predators such as cats to control rodent pest problems around farms and homesteads is common across the world. However, practical scientific evidence on the impact of such biological control in agricultural settings is often lacking. We tested whether the presence of domestic cats and/or dogs in rural homesteads would affect the foraging behaviour of pest rodents. We estimated giving up densities (GUDs from established feeding patches and estimated relative rodent activity using tracking tiles at 40 homesteads across four agricultural communities. We found that the presence of cats and dogs at the same homestead significantly reduced activity and increased GUDs (i.e. increased perception of foraging cost of pest rodent species. However, if only cats or dogs alone were present at the homestead there was no observed difference in rodent foraging activity in comparison to homesteads with no cats or dogs. Our results suggest that pest rodent activity can be discouraged through the presence of domestic predators. When different types of predator are present together they likely create a heightened landscape of fear for foraging rodents.

  7. Catecholamines of the body tissues and radiosensitivity of rodents

    Energy Technology Data Exchange (ETDEWEB)

    Grayevskaya, V M; Zolotariova, N N [AN SSSR, Moscow. Inst. Morfologii Zhivotnykh

    1975-01-01

    Various species of rodents are distinguished by their radiosensitivity (increasing): bank vole < Wistar rat < wild mouse < CC/sub 57/Br mouse < golden hamster < BALB mouse < guinea pig. There is a positive correlation between radiosensitivity of these species and catecholamines content in the adrenals, urea and blood; and negative correlation between radiosensitivity and adrenaline and noradrenaline concentrations in liver and spleen cells. Presumable causes of this correlation, and the possibility of application of the index under study for predicting the organism radiosensitivity and forecasting the outcome of radiation damage are discussed.

  8. Catecholamines of the body tissues and radiosensitivity of rodents

    International Nuclear Information System (INIS)

    Grayevskaya, V.M.; Zolotariova, N.N.

    1975-01-01

    Various species of rodents are distinguished by their radiosensitivity (increasing): bank vole 57 Br mouse < golden hamster < BALB mouse < guinea pig. There is a positive correlation between radiosensitivity of these species and catecholamines content in the adrenals, urea and blood; and negative correlation between radiosensitivity and adrenaline and noradrenaline concentrations in liver and spleen cells. Presumable causes of this correlation, and the possibility of application of the index under study for predicting the organism radiosensitivity and forecasting the outcome of radiation damage are discussed

  9. A multiplex panel of microsatellite markers for widespread subsaharan rodents of the genus Mastomys

    NARCIS (Netherlands)

    Galan, M.; Hooft, van W.F.; Legrand, D.; Berthier, K.; Loiseau, A.; Granjon, L.; Cosson, J.F.

    2004-01-01

    We isolated and characterized 12 polymorphic microsatellite loci in the sub-Saharan rodent Mastomys huberti. We tested cross-species amplification of all these loci in three closely related Mastomys species: M. coucha, M. erythroleucus and M. natalensis. Multiplex panels comprising 11 loci were

  10. Two New Mylagaulid Rodents from the Early Miocene of China.

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    Xiaoyu Lu

    Full Text Available Mylagaulid fossorial rodents are a common component of North American Miocene fossil faunas. However outside of North America, only three species are known from Asia. Here we report two new mylagaulids, Irtyshogaulus minor gen. et sp. nov. and Irtyshogaulus major gen. et sp. nov., recovered from early Miocene sediments in the Junggar Basin in northwestern China. The two new taxa are small-sized, high-crowned promylagauline rodents. Their lower molars possess high metastylid crests, small mesostylids, broad and posterolingually expanded labial inflections, and transversely extending metalophid IIs. The mesoconid is absent in both species. The anterior and posterior fossettids are large and equally developed. Their upper M1-2s possess a square occlusal surface with five deep fossettes. The two new taxa are distinguished from each other mainly by their size, the morphology of fossettes and fossettids, development of mesial and distal lophs, posterior reduction of M3, and the orientation of m2 hypolophid. Our phylogenetic analysis indicates that Irtyshogaulus and Lamugaulus (another early Miocene Asian mylagaulid are sister taxa. The two genera are nested among the North American promylagaulines, and share a common ancestor from North America, indicating early Miocene intercontinental dispersal within this clade of rodents.

  11. Sexual selection halts the relaxation of protamine 2 among rodents.

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    Lena Lüke

    Full Text Available Sexual selection has been proposed as the driving force promoting the rapid evolutionary changes observed in some reproductive genes including protamines. We test this hypothesis in a group of rodents which show marked differences in the intensity of sexual selection. Levels of sperm competition were not associated with the evolutionary rates of protamine 1 but, contrary to expectations, were negatively related to the evolutionary rate of cleaved- and mature-protamine 2. Since both domains were found to be under relaxation, our findings reveal an unforeseen role of sexual selection: to halt the degree of degeneration that proteins within families may experience due to functional redundancy. The degree of relaxation of protamine 2 in this group of rodents is such that in some species it has become dysfunctional and it is not expressed in mature spermatozoa. In contrast, protamine 1 is functionally conserved but shows directed positive selection on specific sites which are functionally relevant such as DNA-anchoring domains and phosphorylation sites. We conclude that in rodents protamine 2 is under relaxation and that sexual selection removes deleterious mutations among species with high levels of sperm competition to maintain the protein functional and the spermatozoa competitive.

  12. Short interspersed elements (SINEs) of the Geomyoidea superfamily rodents.

    Science.gov (United States)

    Gogolevsky, Konstantin P; Kramerov, Dmitri A

    2006-05-24

    A new short interspersed element (SINE) was isolated from the genome of desert kangaroo rat (Dipodomys deserti) using single-primer PCR. This SINE consists of two monomers: the left monomer (IDL) resembles rodent ID element and other tRNAAla(CGC)-derived SINEs, whereas the right one (Geo) shows no similarity with known SINE sequences. PCR and hybridization analyses demonstrated that IDL-Geo SINE is restricted to the rodent superfamily Geomyoidea (families Geomyidea and Heteromyidea). Isolation and analysis of IDL-Geo from California pocket mouse (Chaetodipus californicus) and Botta's pocket gopher (Thomomys bottae) revealed some species-specific features of this SINE family. The structure and evolution of known dimeric SINEs are discussed.

  13. Forest rodents provide directed dispersal of Jeffrey pine seeds

    Science.gov (United States)

    Briggs, J.S.; Wall, S.B.V.; Jenkins, S.H.

    2009-01-01

    Some species of animals provide directed dispersal of plant seeds by transporting them nonrandomly to microsites where their chances of producing healthy seedlings are enhanced. We investigated whether this mutualistic interaction occurs between granivorous rodents and Jeffrey pine (Pinus jeffreyi) in the eastern Sierra Nevada by comparing the effectiveness of random abiotic seed dispersal with the dispersal performed by four species of rodents: deer mice (Peromyscus maniculatus), yellow-pine and long-eared chipmunks (Tamias amoenus and T. quadrimaculatus), and golden-mantled ground squirrels (Spermophilus lateralis). We conducted two caching studies using radio-labeled seeds, the first with individual animals in field enclosures and the second with a community of rodents in open forest. We used artificial caches to compare the fates of seeds placed at the range of microsites and depths used by animals with the fates of seeds dispersed abiotically. Finally, we examined the distribution and survival of naturally establishing seedlings over an eight-year period.Several lines of evidence suggested that this community of rodents provided directed dispersal. Animals preferred to cache seeds in microsites that were favorable for emergence or survival of seedlings and avoided caching in microsites in which seedlings fared worst. Seeds buried at depths typical of animal caches (5–25 mm) produced at least five times more seedlings than did seeds on the forest floor. The four species of rodents differed in the quality of dispersal they provided. Small, shallow caches made by deer mice most resembled seeds dispersed by abiotic processes, whereas many of the large caches made by ground squirrels were buried too deeply for successful emergence of seedlings. Chipmunks made the greatest number of caches within the range of depths and microsites favorable for establishment of pine seedlings. Directed dispersal is an important element of the population dynamics of Jeffrey pine, a

  14. Morphology captures diet and locomotor types in rodents.

    Science.gov (United States)

    Verde Arregoitia, Luis D; Fisher, Diana O; Schweizer, Manuel

    2017-01-01

    To understand the functional meaning of morphological features, we need to relate what we know about morphology and ecology in a meaningful, quantitative framework. Closely related species usually share more phenotypic features than distant ones, but close relatives do not necessarily have the same ecologies. Rodents are the most diverse group of living mammals, with impressive ecomorphological diversification. We used museum collections and ecological literature to gather data on morphology, diet and locomotion for 208 species of rodents from different bioregions to investigate how morphological similarity and phylogenetic relatedness are associated with ecology. After considering differences in body size and shared evolutionary history, we find that unrelated species with similar ecologies can be characterized by a well-defined suite of morphological features. Our results validate the hypothesized ecological relevance of the chosen traits. These cranial, dental and external (e.g. ears) characters predicted diet and locomotion and showed consistent differences among species with different feeding and substrate use strategies. We conclude that when ecological characters do not show strong phylogenetic patterns, we cannot simply assume that close relatives are ecologically similar. Museum specimens are valuable records of species' phenotypes and with the characters proposed here, morphology can reflect functional similarity, an important component of community ecology and macroevolution.

  15. Hantavirus pulmonary syndrome and rodent reservoirs in the savanna-like biome of Brazil's southeastern region.

    Science.gov (United States)

    Limongi, J E; Oliveira, R C; Guterres, A; Costa Neto, S F; Fernandes, J; Vicente, L H B; Coelho, M G; Ramos, V N; Ferreira, M S; Bonvicino, C R; D'Andrea, P S; Lemos, E R S

    2016-04-01

    This paper describes the diversity of rodent fauna in an area endemic for hantavirus cardiopulmonary syndrome (HCPS) in Brazil, the population dynamics and the relationship of rodents with hantavirus in the Cerrado (savanna-like) biome. Additionally, an analysis is made of the partial S segment sequences of the hantaviruses obtained from serologically confirmed human HCPS cases and from rodent specimens. Rodents were collected during four campaigns. Human serum samples were collected from suspected cases of HCPS at hospitals in the state of Minas Gerais. The samples antibody-reactive by ELISA were processed by RT-PCR. The PCR product was amplified and sequenced. Hantavirus was detected only in Necromys lasiurus, the wild rodent species most prevalent in the Cerrado biome (min-max: 50-83·7%). All the six human serum samples were hantavirus seropositive and five showed amplified PCR products. The analysis of the nucleotide sequences showed the circulation of a single genotype, the Araraquara hantavirus. The environmental changes that have occurred in the Cerrado biome in recent decades have favoured N. lasiurus in interspecific competition of habitats, thus increasing the risk of contact between humans and rodent species infected with hantavirus. Our data corroborate the definition of N. lasiurus as the main hantavirus reservoir in the Cerrado biome.

  16. Public health implications of changing rodent importation patterns— United States, 1999–2013

    Science.gov (United States)

    Lankau, Emily W.; Sinclair, Julie R.; Schroeder, Betsy A.; Galland, G. Gale; Marano, Nina

    2015-01-01

    Summary The United States imports a large volume of live wild and domestic animal species; these animals pose a demonstrated risk for introduction of zoonotic diseases. Rodents are imported for multiple purposes, including scientific research, zoo exhibits, and the pet trade. Current U.S. public health regulatory restrictions specific to rodent importation pertain only to those of African origin. To understand the impacts of these regulations and the potential public health risks of international rodent trade to the United States, we evaluated live rodent import records during 1999 –2013 by shipment volume and geographic origin, source (e.g., wild -caught versus captive-or commercially bred), intended purpose, and rodent taxonomy. Live rodent imports increased from 2,737 animals during 1999 to 173,761 animals during 2013. Increases in both the number and size of shipments contributed to this trend. The proportion of wild-captured imports declined from 75% during 1999 to guinea pigs, and hamsters arriving from other countries in North America were predominant taxa underlying this trend . After 2003, African-origin imports became sporadic events under the federal permit process. These patterns suggest development of large -scale captive rodent breeding markets abroad for commercial sale in the United States. While the shift from wild-captured imports alleviates many conservation concerns and risks for novel disease emergence, such consolidated sourcing might elevate exposure risks for zoonotic diseases associated with high-density rodent breeding(e.g. , lymphocytic choriomeningitis or salmonellosis). A responsive border health system must periodically re-evaluate importation regulations in conjunction with key stakeholders to ensure a balance between the economic benefits of rodent trade against the potential public health risks. PMID:26245515

  17. Public Health Implications of Changing Rodent Importation Patterns - United States, 1999-2013.

    Science.gov (United States)

    Lankau, E W; Sinclair, J R; Schroeder, B A; Galland, G G; Marano, N

    2017-04-01

    The United States imports a large volume of live wild and domestic animal species; these animals pose a demonstrated risk for introduction of zoonotic diseases. Rodents are imported for multiple purposes, including scientific research, zoo exhibits and the pet trade. Current U.S. public health regulatory restrictions specific to rodent importation pertain only to those of African origin. To understand the impacts of these regulations and the potential public health risks of international rodent trade to the United States, we evaluated live rodent import records during 1999-2013 by shipment volume and geographic origin, source (e.g. wild-caught versus captive- or commercially bred), intended purpose and rodent taxonomy. Live rodent imports increased from 2737 animals during 1999 to 173 761 animals during 2013. Increases in both the number and size of shipments contributed to this trend. The proportion of wild-captured imports declined from 75% during 1999 to guinea pigs and hamsters arriving from other countries in North America were predominant taxa underlying this trend. After 2003, African-origin imports became sporadic events under the federal permit process. These patterns suggest development of large-scale captive rodent breeding markets abroad for commercial sale in the United States. While the shift from wild-captured imports alleviates many conservation concerns and risks for novel disease emergence, such consolidated sourcing might elevate exposure risks for zoonotic diseases associated with high-density rodent breeding (e.g. lymphocytic choriomeningitis or salmonellosis). A responsive border health system must periodically re-evaluate importation regulations in conjunction with key stakeholders to ensure a balance between the economic benefits of rodent trade against the potential public health risks. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  18. Bartonella in Rodents and Ectoparasites in the Canary Islands, Spain: New Insights into Host-Vector-Pathogen Relationships.

    Science.gov (United States)

    Abreu-Yanes, Estefania; Martin-Alonso, Aaron; Martin-Carrillo, Natalia; Livia, Katherine Garcia; Marrero-Gagliardi, Alessandro; Valladares, Basilio; Feliu, Carlos; Foronda, Pilar

    2018-01-01

    Bartonella genus is comprised of several species of zoonotic relevance and rodents are reservoirs for some of these Bartonella species. As there were no data about the range of Bartonella species circulating among rodents in the Canary Islands, our main aim was to overcome this lack of knowledge by targeting both the citrate synthase (gltA) and the RNA polymerase beta subunit (rpoB) genes. A total of 181 small mammals and 154 ectoparasites were obtained in three of the Canary Islands, namely Tenerife, La Palma, and Lanzarote. The overall prevalence of Bartonella DNA in rodents was 18.8%, whereas the prevalence in ectoparasites was 13.6%. Bartonella sequences closely related to the zoonotic species Bartonella elizabethae, Bartonella tribocorum, and Bartonella rochalimae were identified in rodents, whereas two different gltA haplotypes similar to B. elizabethae were also detected in fleas. Furthermore, Bartonella queenslandensis DNA was also identified in rodents. A strong host specificity was observed, since B. elizabethae DNA was only found in Mus musculus domesticus, whereas gltA and rpoB sequences closely related to the rest of Bartonella species were only identified in Rattus rattus, which is probably due to the host specificity of the arthropod species that act as vectors in these islands. Our results indicate that humans may contract Bartonella infection by contact with rodents in the Canary Islands.

  19. Rhipicephalus sanguineus sensu lato(Ixodidae in synantropic rodents in Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Kathleen Tavares Winkel

    Full Text Available Rhipicephalus sanguineus, the brown dog tick, is responsible for maintaining and transmitting various pathogens, both in animals and human beings, and it is of great sanitary importance. This communication reports the first occurrence of Rhipicephalus sanguineus sensu lato parasitizing Rattus norvegicus in the state of Rio Grande do Sul, Brazil, and it is also the first record of this tick species parasitizing Rattus rattus in Brazil. The rodents were captured from the port area, located in the city of Pelotas, Rio Grande do Sul, Brazil. We collected 6 larvae of this tick species from 2 male R. rattus individuals, and 3 larvae from 2 female R. norvegicus individuals; parasitized specimens of both rodent species were captured from different sites within the experimental area. This record broadens the number of Rhipicephalus sanguineus sensu lato hosts in urban areas, indicating the need for continued monitoring on population density for both R. sanguineus and synanthropic rodents.

  20. Rodent Models for Metabolic Syndrome Research

    Directory of Open Access Journals (Sweden)

    Sunil K. Panchal

    2011-01-01

    Full Text Available Rodents are widely used to mimic human diseases to improve understanding of the causes and progression of disease symptoms and to test potential therapeutic interventions. Chronic diseases such as obesity, diabetes and hypertension, together known as the metabolic syndrome, are causing increasing morbidity and mortality. To control these diseases, research in rodent models that closely mimic the changes in humans is essential. This review will examine the adequacy of the many rodent models of metabolic syndrome to mimic the causes and progression of the disease in humans. The primary criterion will be whether a rodent model initiates all of the signs, especially obesity, diabetes, hypertension and dysfunction of the heart, blood vessels, liver and kidney, primarily by diet since these are the diet-induced signs in humans with metabolic syndrome. We conclude that the model that comes closest to fulfilling this criterion is the high carbohydrate, high fat-fed male rodent.

  1. Responses of nocturnal rodents to shrub encroachment in Banni grasslands, Gujarat, India

    Science.gov (United States)

    Jayadevan, A.

    2016-12-01

    Shrub encroachment is one of the greatest threats to grasslands globally. These woodlands can strongly influence the behaviour of small mammals adapted to more open habitats, which rely on high visibility for early detection of predators. In semi-arid grasslands, rodents are considered keystone species. Although shrub encroachment is known to negatively affect rodent assemblages, its impact on the foraging behaviour of rodents, which is known to vary in response to risky situations, is unknown. Understanding whether shrub encroachment alters such antipredator behaviour is important as antipredator behaviour can alter the distribution, abundance and ultimately, survival of prey species. In this study, I explored the effects of shrub encroachment on the foraging behaviour of nocturnal rodent communities in the Banni grasslands, India. I examined foraging behaviour, quantified using the giving-up density (GUD) framework and the number of rodent crossings around food patches, in two habitats that differed in the extent of shrub encroachment. Under the GUD framework, the amount of food left behind by a forager in a food patch reflects the costs of feeding at the patch. Higher GUDs imply higher foraging costs. I also investigated how removal of an invasive woody plant, Prosopis juliflora would affect foraging behaviour of nocturnal rodents. High shrub encroachment was associated with higher foraging costs (higher GUDs) and lower activity than the sparsely wooded habitat, likely due to low visibility in the densely wooded habitat. The dense habitat also supported a higher richness and relative abundance of generalist rodents than the sparse habitat, likely due to the increased heterogeneity of the habitat. The tree removal experiment revealed that rodents had lower GUDs (i.e., low foraging costs) after the event of tree cutting. This may be due to the reduction of cover in the habitat, leading to higher visibility and lower predation risk. My results suggest that shrub

  2. Food habits of rodents inhabiting arid and semi-arid ecosystems of central New Mexico

    Science.gov (United States)

    Hope, Andrew G.; Parmenter, Robert R.

    2007-01-01

    In this study, we describe seasonal dietary composition for 15 species of rodents collected in all major habitats on the Sevilleta National Wildlife Refuge (Socorro County) in central New Mexico. A comprehensive literature review of food habits for these species from throughout their distribution also is provided. We collected rodents in the field during winter, spring and late summer in 1998 from six communities: riparian cottonwood forest; piñon-juniper woodland; juniper-oak savanna; mesquite savanna; short-grass steppe; and Chihuahuan Desert scrubland. Rodents included Spermophilus spilosoma (Spotted Ground Squirrel), Perognathus flavescens (Plains Pocket Mouse), Perognathus flavus (Silky Pocket Mouse), Dipodomys merriami (Merriam’s Kangaroo Rat), Dipodomys ordii (Ord’s Kangaroo Rat), Dipodomys spectabilis (Banner-tailed Kangaroo Rat), Reithrodontomys megalotis (Western Harvest Mouse), Peromyscus boylii (Brush Mouse), Peromyscus eremicus (Cactus Mouse), Peromyscus leucopus (White-footed Mouse), Peromyscus truei (Piñon Mouse), Onychomys arenicola (Mearn’s Grasshopper Mouse), Onychomys leucogaster (Northern Grasshopper Mouse), Neotoma albigula/leucodon (White-throated Woodrats), and Neotoma micropus (Southern Plains Woodrat). We collected stomach contents of all species, and cheek-pouch contents of heteromyids, and quantified them in the laboratory. We determined seasonal diets in each habitat by calculating mean percentage volumes of seeds, arthropods and green vegetation (plant leaves and stems) for each species of rodent. Seeds consumed by each rodent were identified to genus, and often species, and quantified by frequency counts. Comparisons of diets between and among species of rodents, seasons, and ecosystems were also examined. We provide an appendix of all plant taxa documented.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

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

    2014-07-01

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

  5. Tactile learning in rodents: Neurobiology and neuropharmacology.

    Science.gov (United States)

    Roohbakhsh, Ali; Shamsizadeh, Ali; Arababadi, Mohammad Kazemi; Ayoobi, Fateme; Fatemi, Iman; Allahtavakoli, Mohammad; Mohammad-Zadeh, Mohammad

    2016-02-15

    Animal models of learning and memory have been the subject of considerable research. Rodents such as mice and rats are nocturnal animals with poor vision, and their survival depends on their sense of touch. Recent reports have shown that whisker somatosensation is the main channel through which rodents collect and process environmental information. This review describes tactile learning in rodents from a neurobiological and neuropharmacological perspective, and how this is involved in memory-related processes. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. [Population change of farmland rodent and the influences of climate and cultivation factors in Fengxian District of Shanghai, China].

    Science.gov (United States)

    Fei, Lei; Wang, Zu-guo; Yao, Yao; Xu, Xiang-ming; Gu, Pin-qiang

    2015-02-01

    We analyzed the changes of rodent population from 1988 to 2013 in Fengxian District, Shanghai, and discussed the relevance of rodent population dynamics and climate, and ecological factors. Results showed that the average rat density was 1.3% from 1988 to 2013, and the dominant species was Apodemus agrarius. There was little change of density between years. The average composition ratio was 97.5%. The peak of rodent density appeared from February to May, highest in March. Average density and peak decreased obviously year after year. Numbers of adult rodents of 1st group were positively correlated, while that of adult rodents of 2nd group and elderly group negatively correlated with years. Rat age presented a shortened trend annually. Rodent density and temperature factors were negatively correlated except in January. Extreme warmth in February had a lagged, positive effect on the rat density. Precipitation factors had no significant correlation with the density of rodents. Relative humidity was positively correlated with the density, mostly. Planting structure adjustment and reduction of planting acreage were significantly correlated with the reduction of rodent density. Increased deratization rate was also correlated with the reduction.

  7. Effects of rodent community diversity and composition on prevalence of an endemic bacterial pathogen - Bartonella

    Science.gov (United States)

    Bai, Y.; Kosoy, M.Y.; Calisher, C.H.; Cully, J.F.; Collinge, S.K.

    2009-01-01

    By studying Bartonella prevalence in rodent communities from 23 geographic sites in the western United States and one site in northern Mexico, the present study focused on the effects of rodent community diversity (measured by richness and Shannon index) and composition on prevalence of Bartonella infections. The analysis showed negative correlations of Bartonella prevalence with rodent richness and Shannon index. Further, Bartonella prevalence varied among rodent genera/species. Three models were applied to explain the observations. (1) Within-species/genus transmission: Bartonella strains usually are host-specific and adding non-host species would decrease Bartonella prevalence in its principal host through reduction of host contact (encounter reduction); (2) Frequency-dependence: Adding hosts would decrease the proportion of all infected individuals in the community, resulting in a reduction in the number of contacts between susceptible and infected individuals that usually leads to transmission (transmission reduction); and (3) Dominant species effect: Dominant species, if not susceptible to Bartonellae, can constrain the abundance of susceptible hosts (susceptible host regulation). These mechanisms work in concert; and the level of Bartonella prevalence is an outcome of regulation of all of these mechanisms on the entire system.

  8. Nonhuman gamblers: lessons from rodents, primates, and robots

    Science.gov (United States)

    Paglieri, Fabio; Addessi, Elsa; De Petrillo, Francesca; Laviola, Giovanni; Mirolli, Marco; Parisi, Domenico; Petrosino, Giancarlo; Ventricelli, Marialba; Zoratto, Francesca; Adriani, Walter

    2014-01-01

    The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offers valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics), to make the case for a greater degree of methodological integration in future studies on pathological gambling. PMID:24574984

  9. Population Ecology of Hantavirus Rodent Hosts in Southern Brazil

    Science.gov (United States)

    Teixeira, Bernardo R.; Loureiro, Nathalie; Strecht, Liana; Gentile, Rosana; Oliveira, Renata C.; Guterres, Alexandro; Fernandes, Jorlan; Mattos, Luciana H. B. V.; Raboni, Sonia M.; Rubio, Giselia; Bonvicino, Cibele R.; Duarte dos Santos, Claudia N.; Lemos, Elba R. S.; D'Andrea, Paulo S.

    2014-01-01

    In this study we analyze population dynamics of hantavirus rodent hosts and prevalence of infection over a 2-year period in Southern Brazil, a region with a high incidence of hantavirus pulmonary syndrome. The 14 small mammal species captured were composed of 10 rodents and four marsupials, the six most abundant species being Akodon serrensis, Oxymycterus judex, Akodon montensis, Akodon paranaensis, Oligoryzomys nigripes, and Thaptomys nigrita. These species displayed a similar pattern with increasing population sizes in fall/winter caused by recruitment and both, increase in reproductive activity and higher hantavirus prevalence in spring/summer. Specific associations between A. montensis/Jaborá Virus (JABV) and O. nigripes/Juquitiba-like Virus (JUQV-like) and spillover infections between A. paranaensis/JABV, A. serrensis/JABV, and A. paranaensis/JUQV-like were observed. Spillover infection in secondary hosts seems to play an important role in maintaining JABV and JUQV-like in the hantavirus sylvatic cycle mainly during periods of low prevalence in primary hosts. PMID:24935954

  10. Detection and Characterization of Homologues of Human Hepatitis Viruses and Pegiviruses in Rodents and Bats in Vietnam.

    Science.gov (United States)

    Van Nguyen, Dung; Van Nguyen, Cuong; Bonsall, David; Ngo, Tue Tri; Carrique-Mas, Juan; Pham, Anh Hong; Bryant, Juliet E; Thwaites, Guy; Baker, Stephen; Woolhouse, Mark; Simmonds, Peter

    2018-02-28

    Rodents and bats are now widely recognised as important sources of zoonotic virus infections in other mammals, including humans. Numerous surveys have expanded our knowledge of diverse viruses in a range of rodent and bat species, including their origins, evolution, and range of hosts. In this study of pegivirus and human hepatitis-related viruses, liver and serum samples from Vietnamese rodents and bats were examined by PCR and sequencing. Nucleic acids homologous to human hepatitis B, C, E viruses were detected in liver samples of 2 (1.3%) of 157 bats, 38 (8.1%), and 14 (3%) of 470 rodents, respectively. Hepacivirus-like viruses were frequently detected (42.7%) in the bamboo rat, Rhizomys pruinosus , while pegivirus RNA was only evident in 2 (0.3%) of 638 rodent serum samples. Complete or near-complete genome sequences of HBV, HEV and pegivirus homologues closely resembled those previously reported from rodents and bats. However, complete coding region sequences of the rodent hepacivirus-like viruses substantially diverged from all of the currently classified variants and potentially represent a new species in the Hepacivirus genus. Of the viruses identified, their routes of transmission and potential to establish zoonoses remain to be determined.

  11. Rodent management: the man/environment interface

    International Nuclear Information System (INIS)

    Jackson, W.B.

    1978-01-01

    Rodents which interact with man generally are regarded as undesirable. Attempts at eliminating such rodents by increasing predation (including traps, microbiological agents, toxicants) have been relatively unsuccessful. Management by environmental manipulation must be basic. This then can be supplemented with predation at critical points where public health, use practices, or imperfections in the system demand. Society mores, practices, and economic considerations also have significant impact on the management system

  12. Rough-legged buzzards, Arctic foxes and red foxes in a tundra ecosystem without rodents.

    Directory of Open Access Journals (Sweden)

    Ivan Pokrovsky

    Full Text Available Small rodents with multi-annual population cycles strongly influence the dynamics of food webs, and in particular predator-prey interactions, across most of the tundra biome. Rodents are however absent from some arctic islands, and studies on performance of arctic predators under such circumstances may be very instructive since rodent cycles have been predicted to collapse in a warming Arctic. Here we document for the first time how three normally rodent-dependent predator species-rough-legged buzzard, arctic fox and red fox - perform in a low-arctic ecosystem with no rodents. During six years (in 2006-2008 and 2011-2013 we studied diet and breeding performance of these predators in the rodent-free Kolguev Island in Arctic Russia. The rough-legged buzzards, previously known to be a small rodent specialist, have only during the last two decades become established on Kolguev Island. The buzzards successfully breed on the island at stable low density, but with high productivity based on goslings and willow ptarmigan as their main prey - altogether representing a novel ecological situation for this species. Breeding density of arctic fox varied from year to year, but with stable productivity based on mainly geese as prey. The density dynamic of the arctic fox appeared to be correlated with the date of spring arrival of the geese. Red foxes breed regularly on the island but in very low numbers that appear to have been unchanged over a long period - a situation that resemble what has been recently documented from Arctic America. Our study suggests that the three predators found breeding on Kolguev Island possess capacities for shifting to changing circumstances in low-arctic ecosystem as long as other small - medium sized terrestrial herbivores are present in good numbers.

  13. A preliminary field survey of ectoparasites of rodents in urban park, Sarawak, Malaysian Borneo.

    Science.gov (United States)

    Madinah, A; Mariana, A; Fatimah, A; Abdullah, M T

    2013-09-01

    A survey of ectoparasites was carried out during Eco-Zoonoses Expedition in Bukit Aup Jubilee Park (BAJP), Sibu, Sarawak, Malaysian Borneo from 5(th) to 9(th) June 2008. A total of nine individuals comprising two species of rodents were captured. The species of rodents screened for ectoparasites were Sundamys muelleri and Callosciurus notatus. Four genera and six species of ectoparasites were collected, namely, Ixodes granulatus, Ixodes sp., Laelaps sedlaceki, Laelaps nuttalli, Hoplopleura dissicula and Listrophoroides sp. Three species of the ectoparasites are known to have potential health risk. The species were Ixodes granulatus, Laelaps nuttalli and Hoplopleura dissicula. This survey produced the first list of ectoparasites in Bukit Aup Jubilee Park, Sarawak, Malaysia.

  14. Patterns of orthopox virus wild rodent hosts in South Germany.

    Science.gov (United States)

    Essbauer, Sandra; Hartnack, Sonja; Misztela, Krystian; Kiessling-Tsalos, Judith; Bäumler, Walter; Pfeffer, Martin

    2009-06-01

    Although cowpox virus (CPXV) infections in a variety of dead-end hosts have been investigated in Germany for more than 50 years, data on species and geographical distribution of CPXV in reservoir hosts are sparse. Here we present the first comprehensive study of 825 rodents that have been collected in Bavaria, Southern Germany. In summary, six different rodent species (Apodemus flavicollis, Myodes glareolus, Microtus arvalis, Apodemus sylvaticus, Microtus agrestis, and Arvicola amphibius) were trapped at three main trapping sites and investigated using a serum neutralization test (SNT). Prevalence of orthopox virus (OPV)-neutralizing antibodies was (with exception of one trapping site) highest in bank voles, ranging from 24.5% to 42.4%; often with SNT titers > or =96. Two up to 25% of yellow-necked mice were OPV sero-positive, but wood mice only at one site with 5.5%. Up to 7.7% of common voles were found to be OPV seroreactive, while M. agrestis and A. amphibius only sporadically showed seroreactivity. Further analyses of a subset of 450 bank voles and yellow-necked mice trapped at one site over a 18-month period revealed that male yellow-necked mice and female gravid yellow-necked mice had significantly more OPV-neutralizing antibodies. Mean body weight and OPV-seroreactivity were significantly negatively associated in male A. flavicollis. This was not due to shorter body length or smaller body mass index, but previously OPV-infected male A. flavicollis had dramatically reduced mean kidney weights. Seroreactivity in female bank voles was positively related to lung weights. We also found that both male yellow-necked mice and male bank voles with positive SNT titers had higher infestation rates with ectoparasites. We here show for the first time that A. flavicollis beside M. glareolus is a hypothetic host for CPXV, and that there are big geographical and spatial variations concerning the seroprevalence in rodent populations in South Germany.

  15. How many food additives are rodent carcinogens?

    Science.gov (United States)

    Johnson, F M

    2002-01-01

    One generally assumes that chemical agents added to foods are reasonably free of risks to human health, and practically everyone consumes some additives in his or her food daily throughout life. In the United States, the 1958 Food Additives Amendment to the Federal Food, Drug and Cosmetic Act of 1938 requires food manufacturers to demonstrate the safety of food additives to the Food and Drug Administration (FDA). The Amendment contains a provision that prohibits approval of an additive if it is found to cause cancer in humans or animals. In the present study, data from the National Toxicology Program rodent bioassay (NTPRB) were used to identify a sample of approximately 50 rodent-tested additives and other chemicals added to food that had been evaluated independently of the FDA/food industry. Surprisingly, the sample shows more than 40% of these food chemicals to be carcinogenic in one or more rodent groups. If this percentage is extrapolated to all substances added to food in the United States, it would imply that more than 1000 of such substances are potential rodent carcinogens. The NTP and FDA test guidelines use similar, though not necessarily identical, rodent test procedures, including near lifetime exposures to the maximum tolerated dose. The FDA specifies that test chemicals should be administered by the oral route. However, the oral route includes three methods of delivering chemicals, that is, mixed in the food or water or delivered by stomach tube (gavage). The NTP data show only 1 of 18 food chemicals mixed in the food are rodent carcinogens, but 16 of 23 gavage-administered food chemicals are carcinogenic to rodents. The distribution suggests that among orally delivered chemicals, those administered in the feed will more likely prove to be noncarcinogens than chemicals given by gavage. The rodent data also reveal that effects may vary according to dose and genotype, as well as by route of administration, to further complicate extrapolation to humans

  16. The need to implement the landscape of fear within rodent pest management strategies

    NARCIS (Netherlands)

    Krijger, Inge M.; Belmain, Steven R.; Singleton, Grant R.; Groot Koerkamp, Peter W.G.; Meerburg, Bastiaan G.

    2017-01-01

    Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically

  17. Rodent Abundance and Hantavirus Infection in Protected Area, East-Central Argentina

    Science.gov (United States)

    Maroli, Malena; Vadell, María Victoria; Padula, Paula

    2018-01-01

    We captured 3 hantavirus rodent hosts in Otamendi Natural Reserve, Argentina, during 2007–2012. Hantavirus antibodies were found only in Akodon azarae grass mice, mainly in males and old animals. Higher abundance of this species was associated with warm and rainy weather and high water levels, which peaked after a strong El Niño event. PMID:29260665

  18. Developmental toxicity of engineered nanomaterials in rodents

    Energy Technology Data Exchange (ETDEWEB)

    Ema, Makoto, E-mail: ema-makoto@aist.go.jp; Gamo, Masashi; Honda, Kazumasa

    2016-05-15

    We summarized significant effects reported in the literature on the developmental toxicity of engineered nanomaterials (ENMs) in rodents. The developmental toxicity of ENMs included not only structural abnormalities, but also death, growth retardation, and behavioral and functional abnormalities. Most studies were performed on mice using an injection route of exposure. Teratogenic effects were indicated when multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), and TiO{sub 2}-nanoparticles were administered to mice during early gestation. Reactive oxygen species levels were increased in placentas and malformed fetuses and their placentas after prenatal exposure to MWCNTs and SWCNTs, respectively. The pre- and postnatal mortalities and growth retardation in offspring increased after prenatal exposure to ENMs. Histopathological and functional abnormalities were also induced in placentas after prenatal exposure to ENMs. Maternal exposure to ENMs induced behavioral alterations, histopathological and biochemical changes in the central nervous system, increased susceptibility to allergy, transplacental genotoxicity, and vascular, immunological, and reproductive effects in offspring. The size- and developmental stage-dependent placental transfer of ENMs was noted after maternal exposure. Silver accumulated in the visceral yolk sac after being injected with Ag-NPs during early gestation. Although currently available data has provided initial information on the potential developmental toxicity of ENMs, that on the developmental toxicity of ENMs is still very limited. Further studies using well-characterized ENMs, state-of the-art study protocols, and appropriate routes of exposure are required in order to clarify these developmental effects and provide information suitable for risk assessments of ENMs. - Highlights: • We review the developmental toxicity studies of engineered nanomaterials (ENMs). • Various developmental endpoints have been

  19. Ecology, Genetic Diversity, and Phylogeographic Structure of Andes Virus in Humans and Rodents in Chile▿

    Science.gov (United States)

    Medina, Rafael A.; Torres-Perez, Fernando; Galeno, Hector; Navarrete, Maritza; Vial, Pablo A.; Palma, R. Eduardo; Ferres, Marcela; Cook, Joseph A.; Hjelle, Brian

    2009-01-01

    Andes virus (ANDV) is the predominant etiologic agent of hantavirus cardiopulmonary syndrome (HCPS) in southern South America. In Chile, serologically confirmed human hantavirus infections have occurred throughout a wide latitudinal distribution extending from the regions of Valparaíso (32 to 33°S) to Aysén (46°S) in southern Patagonia. In this study, we found seropositive rodents further north in the Coquimbo region (30°S) in Chile. Rodent seroprevalence was 1.4%, with Oligoryzomys longicaudatus displaying the highest seroprevalence (5.9%), followed by Abrothrix longipilis (1.9%) and other species exhibiting ≤0.6% seropositivity. We sequenced partial ANDV small (S) segment RNA from 6 HCPS patients and 32 rodents of four different species collected throughout the known range of hantavirus infection in Chile. Phylogenetic analyses showed two major ANDV South (ANDV Sout) clades, congruent with two major Chilean ecoregions, Mediterranean (Chilean matorral [shrubland]) and Valdivian temperate forest. Human and rodent samples grouped according to geographic location. Phylogenetic comparative analyses of portions of S and medium segments (encoding glycoproteins Gn and Gc) from a subset of rodent specimens exhibited similar topologies, corroborating two major ANDV Sout clades in Chile and suggesting that yet unknown factors influence viral gene flow and persistence throughout the two Chilean ecoregions. Genetic algorithms for recombination detection identified recombination events within the S segment. Molecular demographic analyses showed that the virus is undergoing purifying selection and demonstrated a recent exponential growth in the effective number of ANDV Sout infections in Chile that correlates with the increased number of human cases reported. Although we determined virus sequences from four rodent species, our results confirmed O. longicaudatus as the primary ANDV Sout reservoir in Chile. While evidence of geographic differentiation exists, a single

  20. The Prevalence of Trypanosoma cruzi, the Causal Agent of Chagas Disease, in Texas Rodent Populations.

    Science.gov (United States)

    Aleman, Adriana; Guerra, Trina; Maikis, Troy J; Milholland, Matthew T; Castro-Arellano, Ivan; Forstner, Michael R J; Hahn, Dittmar

    2017-03-01

    Rodent species were assessed as potential hosts of Trypanosoma cruzi, the etiologic agent of Chagas disease, from five sites throughout Texas in sylvan and disturbed habitats. A total of 592 rodents were captured, resulting in a wide taxonomic representation of 11 genera and 15 species. Heart samples of 543 individuals were successfully analyzed by SybrGreen-based quantitative PCR (qPCR) targeting a 166 bp fragment of satellite DNA of T. cruzi. Eight rodents representing six species from six genera and two families were infected with T. cruzi. This is the first report of T. cruzi in the pygmy mouse (Baiomys taylori) and the white-footed mouse (Peromyscus leucopus) for the USA. All infected rodents were from the southernmost site (Las Palomas Wildlife Management Area). No differences in pathogen prevalence existed between disturbed habitats (5 of 131 tested; 3.8%) and sylvan habitats (3 of 40 tested; 7.5%). Most positives (n = 6, 16% prevalence) were detected in late winter with single positives in both spring (3% prevalence) and fall (1% prevalence). Additionally, 30 Triatoma insects were collected opportunistically from sites in central Texas. Fifty percent of these insects, i.e., 13 T. gerstaeckeri (68%), and two T. lecticularia (100%) were positive for T. cruzi. Comparative sequence analyses of 18S rRNA of samples provided identical results with respect to detection of the presence or absence of T. cruzi and assigned T. cruzi from rodents collected in late winter to lineage TcI. T. cruzi from Triatoma sp. and rodents from subsequent collections in spring and fall were different, however, and could not be assigned to other lineages with certainty.

  1. Lawsonia intracellularis in the feces of wild rodents and stray cats captured around equine farms.

    Science.gov (United States)

    Hwang, Jeong-Min; Seo, Myung-Ji; Yeh, Jung-Yong

    2017-08-11

    Proliferative enteropathy is a global enteric disease of particular importance in pigs. The causative bacterium, Lawsonia intracellularis, has a wide range of susceptible host species. Recently, L. intracellularis has been recognized as an etiologic agent of an emerging enteric disease in foals called equine proliferative enteropathy (EPE). The presence of L. intracellularis in nonruminant wildlife has raised questions regarding the role of these species in EPE transmission. This study investigated exposure to L. intracellularis in wild rodents and feral cats from eight farms with confirmed EPE. Serum (42) and fecal (40) samples from resident foals and fecal samples (131), intestinal mucosa tissues (14), and mesenteric lymph nodes (14) from wild and feral animals were collected for the evaluation of the farm status and the molecular detection of L. intracellularis following the diagnosis of EPE in index cases. Fresh feces from wild rodents and feral cats were collected from the ground while walking the premises or after trapping the animals using live traps. A total of 3 brown rats, 7 house mice, 1 striped field mouse, 2 grey red-backed voles, and 3 feral cats showed evidence of prior exposure to L. intracellularis. Our data add to increasing evidence demonstrating the potential for L. intracellularis transmission and infection in wild rodents and feral cats and provide possible evidence of interspecies transmission. The exposure of wild rodents and feral cats provides potential evidence for the spillover of L. intracellularis to wildlife species and raises the question of spillback to horses. Additionally, these animals may represent an indicator of environmental exposure or may be actively involved in the transmission of L. intracellularis to foals by acting as potential reservoir/amplifier hosts. This study is the first to demonstrate the magnitude of L. intracellularis shedding in the feces of wild rodents and feral cats and to indicate the significant

  2. Conspecific Interactions in Adult Laboratory Rodents: Friends or Foes?

    Science.gov (United States)

    Lukas, Michael; de Jong, Trynke R

    2017-01-01

    Interactions between adult conspecifics, including sexual behaviors, affiliation, and aggression are crucial for the well-being, survival, and reproduction of mammals. This holds true for any mammalian species, but certainly for humans: An inability to optimally navigate the social system can have a strong negative impact on physical and mental health. Translational rodent models have been used for decades to unravel the neural pathways and substrates involved in normal and abnormal conspecific interactions. Researchers in the field of translational social neuroscience face a double challenge: Not only do they need to pay considerable attention to the behavioral ecology of their model species or their ancestors, they also have to expect a relatively large variability in behavior and adjust their experimental design accordingly. In this chapter, we will lay out traditional and novel rodent models and paradigms to study sexual, affiliative, and aggressive interactions among adult conspecifics. We will discuss the merits and main findings and briefly consider the most promising novel directions. Finally, we review the modulatory involvement of two major players in mammal social interaction: the central oxytocin and vasopressin system.

  3. Hemoglobin affinity in Andean rodents

    Directory of Open Access Journals (Sweden)

    HRVOJ OSTOJIC

    2002-01-01

    Full Text Available Blood hemoglobin oxygen affinity (P50 was measured in three Andean species and in the laboratory rat (control, all raised near sea level. Chinchilla lanigera (Molina, 1792 has an altitudinal habitat range from low Andean slopes up to 3000 m., while Chinchilla brevicaudata (Waterhouse, 1848 has an altitudinal range from 3000 to 5000 m. The laboratory type guinea pig, wild type guinea pig (Cavia porcellus, (Waterhouse, 1748, and laboratory rat (Rattus norvegicus were also raised at sea level. The Andean species had high hemoglobin oxygen affinities (low P50 compared with the rat. Chinchilla brevicaudata had a higher affinity than Chinchilla lanigera. The wild type guinea pig had a higher affinity than the laboratory type. As has been shown in other species, this is another example of an inverse correlation between the altitude level and the P50 values. This is the first hemoglobin oxygen affinity study in Chinchilla brevicaudata.

  4. Translational Rodent Models for Research on Parasitic Protozoa-A Review of Confounders and Possibilities.

    Science.gov (United States)

    Ehret, Totta; Torelli, Francesca; Klotz, Christian; Pedersen, Amy B; Seeber, Frank

    2017-01-01

    Rodents, in particular Mus musculus , have a long and invaluable history as models for human diseases in biomedical research, although their translational value has been challenged in a number of cases. We provide some examples in which rodents have been suboptimal as models for human biology and discuss confounders which influence experiments and may explain some of the misleading results. Infections of rodents with protozoan parasites are no exception in requiring close consideration upon model choice. We focus on the significant differences between inbred, outbred and wild animals, and the importance of factors such as microbiota, which are gaining attention as crucial variables in infection experiments. Frequently, mouse or rat models are chosen for convenience, e.g., availability in the institution rather than on an unbiased evaluation of whether they provide the answer to a given question. Apart from a general discussion on translational success or failure, we provide examples where infections with single-celled parasites in a chosen lab rodent gave contradictory or misleading results, and when possible discuss the reason for this. We present emerging alternatives to traditional rodent models, such as humanized mice and organoid primary cell cultures. So-called recombinant inbred strains such as the Collaborative Cross collection are also a potential solution for certain challenges. In addition, we emphasize the advantages of using wild rodents for certain immunological, ecological, and/or behavioral questions. The experimental challenges (e.g., availability of species-specific reagents) that come with the use of such non-model systems are also discussed. Our intention is to foster critical judgment of both traditional and newly available translational rodent models for research on parasitic protozoa that can complement the existing mouse and rat models.

  5. Vision in laboratory rodents-Tools to measure it and implications for behavioral research.

    Science.gov (United States)

    Leinonen, Henri; Tanila, Heikki

    2017-07-29

    Mice and rats are nocturnal mammals and their vision is specialized for detection of motion and contrast in dim light conditions. These species possess a large proportion of UV-sensitive cones in their retinas and the majority of their optic nerve axons target superior colliculus rather than visual cortex. Therefore, it was a widely held belief that laboratory rodents hardly utilize vision during day-time behavior. This dogma is being questioned as accumulating evidence suggests that laboratory rodents are able to perform complex visual functions, such as perceiving subjective contours, and that declined vision may affect their performance in many behavioral tasks. For instance, genetic engineering may have unexpected consequences on vision as mouse models of Alzheimer's and Huntington's diseases have declined visual function. Rodent vision can be tested in numerous ways using operant training or reflex-based behavioral tasks, or alternatively using electrophysiological recordings. In this article, we will first provide a summary of visual system and explain its characteristics unique to rodents. Then, we present well-established techniques to test rodent vision, with an emphasis on pattern vision: visual water test, optomotor reflex test, pattern electroretinography and pattern visual evoked potentials. Finally, we highlight the importance of visual phenotyping in rodents. As the number of genetically engineered rodent models and volume of behavioral testing increase simultaneously, the possibility of visual dysfunctions needs to be addressed. Neglect in this matter potentially leads to crude biases in the field of neuroscience and beyond. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Translational Rodent Models for Research on Parasitic Protozoa—A Review of Confounders and Possibilities

    Directory of Open Access Journals (Sweden)

    Totta Ehret

    2017-06-01

    Full Text Available Rodents, in particular Mus musculus, have a long and invaluable history as models for human diseases in biomedical research, although their translational value has been challenged in a number of cases. We provide some examples in which rodents have been suboptimal as models for human biology and discuss confounders which influence experiments and may explain some of the misleading results. Infections of rodents with protozoan parasites are no exception in requiring close consideration upon model choice. We focus on the significant differences between inbred, outbred and wild animals, and the importance of factors such as microbiota, which are gaining attention as crucial variables in infection experiments. Frequently, mouse or rat models are chosen for convenience, e.g., availability in the institution rather than on an unbiased evaluation of whether they provide the answer to a given question. Apart from a general discussion on translational success or failure, we provide examples where infections with single-celled parasites in a chosen lab rodent gave contradictory or misleading results, and when possible discuss the reason for this. We present emerging alternatives to traditional rodent models, such as humanized mice and organoid primary cell cultures. So-called recombinant inbred strains such as the Collaborative Cross collection are also a potential solution for certain challenges. In addition, we emphasize the advantages of using wild rodents for certain immunological, ecological, and/or behavioral questions. The experimental challenges (e.g., availability of species-specific reagents that come with the use of such non-model systems are also discussed. Our intention is to foster critical judgment of both traditional and newly available translational rodent models for research on parasitic protozoa that can complement the existing mouse and rat models.

  7. Morphological evolution, ecological diversification and climate change in rodents.

    Science.gov (United States)

    Renaud, Sabrina; Michaux, Jacques; Schmidt, Daniela N; Aguilar, Jean-Pierre; Mein, Pierre; Auffray, Jean-Christophe

    2005-03-22

    Among rodents, the lineage from Progonomys hispanicus to Stephanomys documents a case of increasing size and dental specialization during an approximately 9 Myr time-interval. On the contrary, some contemporaneous generalist lineages like Apodemus show a limited morphological evolution. Dental shape can be related to diet and can be used to assess the ecological changes along the lineages. Consequently, size and shape of the first upper molar were measured in order to quantify the patterns of morphological evolution along both lineages and compare them to environmental trends. Climatic changes do not have a direct influence on evolution, but they open new ecological opportunities by changing vegetation and allow the evolution of a specialist like Stephanomys. On the other hand, environmental changes are not dramatic enough to destroy the habitat of a long-term generalist like Apodemus. Hence, our results exemplify a case of an influence of climate on the evolution of specialist species, although a generalist species may persist without change.

  8. Fellow travellers: Working memory and mental time travel in rodents.

    Science.gov (United States)

    Dere, Ekrem; Dere, Dorothea; de Souza Silva, Maria Angelica; Huston, Joseph P; Zlomuzica, Armin

    2017-03-19

    The impairment of mental time travel is a severe cognitive symptom in patients with brain lesions and a number of neuropsychiatric disorders. Whether animals are also able to mentally travel in time both forward and backward is still a matter of debate. In this regard, we have proposed a continuum of mental time travel abilities across different animal species, with humans being the species with the ability to perform most sophisticated forms of mental time travel. In this review and perspective article, we delineate a novel approach to understand the evolution, characteristics and function of human and animal mental time travel. Furthermore, we propose a novel approach to measure mental time travel in rodents in a comprehensive manner using a test battery composed of well-validated and easy applicable tests. Copyright © 2017. Published by Elsevier B.V.

  9. Multilocus phylogeny of East African gerbils (Rodentia, Gerbilliscus) illuminates the history of the Somali-Masai savanna

    Czech Academy of Sciences Publication Activity Database

    Aghová, Tatiana; Šumbera, R.; Piálek, L.; Mikula, Ondřej; McDonough, M. M.; Lavrenchenko, L. A.; Meheretu, Y.; Mbau, J. S.; Bryja, Josef

    2017-01-01

    Roč. 44, č. 10 (2017), s. 2295-2307 ISSN 0305-0270 R&D Projects: GA ČR GAP506/10/0983; GA ČR GA15-20229S Institutional support: RVO:68081766 Keywords : biogeography * Gerbillinae * historical DNA * murid rodents * phylogeography * Plio-Pleistocene climate change * pyrosequencing * Rift Valley * species delimitation * tropical Africa Subject RIV: EG - Zoology OBOR OECD: Ecology Impact factor: 4.248, year: 2016

  10. Unpredictability of escape trajectory explains predator evasion ability and microhabitat preference of desert rodents.

    Science.gov (United States)

    Moore, Talia Y; Cooper, Kimberly L; Biewener, Andrew A; Vasudevan, Ramanarayan

    2017-09-05

    Mechanistically linking movement behaviors and ecology is key to understanding the adaptive evolution of locomotion. Predator evasion, a behavior that enhances fitness, may depend upon short bursts or complex patterns of locomotion. However, such movements are poorly characterized by existing biomechanical metrics. We present methods based on the entropy measure of randomness from Information Theory to quantitatively characterize the unpredictability of non-steady-state locomotion. We then apply the method by examining sympatric rodent species whose escape trajectories differ in dimensionality. Unlike the speed-regulated gait use of cursorial animals to enhance locomotor economy, bipedal jerboa (family Dipodidae) gait transitions likely enhance maneuverability. In field-based observations, jerboa trajectories are significantly less predictable than those of quadrupedal rodents, likely increasing predator evasion ability. Consistent with this hypothesis, jerboas exhibit lower anxiety in open fields than quadrupedal rodents, a behavior that varies inversely with predator evasion ability. Our unpredictability metric expands the scope of quantitative biomechanical studies to include non-steady-state locomotion in a variety of evolutionary and ecologically significant contexts.Biomechanical understanding of animal gait and maneuverability has primarily been limited to species with more predictable, steady-state movement patterns. Here, the authors develop a method to quantify movement predictability, and apply the method to study escape-related movement in several species of desert rodents.

  11. Comparing strategies for controlling an African pest rodent: an empirically based theoretical study

    DEFF Research Database (Denmark)

    Stenseth, Nils Chr.; Leirs, Herwig; Mercelis, Saskia

    2001-01-01

    of rats. Control measures affecting survival as well as reproduction were considered.4. The model showed that control measures reducing survival will only have long-term effects on population size if they are also applied when rodent densities are low. Control measures applied only when rodent densities...... are high will not have persistent effects, even at high mortality rates.5. The model demonstrated that control measures reducing reproduction are likely to prevent Mastomys outbreaks, but will keep densities low over a long period only when the contraceptive effect is strong (> 75% reduction).6. Provided...... in particular cause major economic losses in Africa through damage to crops. Attempts to develop dynamic population models for this and other pest rodents are ongoing. 2. Demographic estimates from a capture-mark-recapture (CMR) study in Tanzania were used to parameterize a population model for this species...

  12. The in vivo rodent test systems for assessment of carcinogenic potential

    DEFF Research Database (Denmark)

    van der Laan, Jan-Willem; Spindler, Per

    2002-01-01

    A Drug Information Association (DIA) workshop was held in May 2001 to discuss the outcome of the International Life Sciences Institute-Health and Environmental Sciences Institute (ILSI-HESI) project on alternative models for carcinogenicity assessment such as the P53(+/-) and XPA(+/-) knockout...... mouse models, the RasH2 and Tg.AC transgenic mouse models, and the neonatal mouse model. The "ICH Guideline S1B on Testing for Carcinogenicity of Pharmaceuticals" advocates that carcinogenicity testing of pharmaceuticals, when needed, might be carried out choosing one 2-year rodent carcinogenicity study...... (rat) plus one other study that supplements the 2-year study and providing additional information that is not readily available from the 2-year study: either (1) a short- or medium-term in vivo rodent test system or (2) a 2-year carcinogenicity study in a second rodent species (mouse). Another topic...

  13. Trichosomoides nasalis (Nematoda: Trichinelloidea in the murid host Arvicanthis niloticus: Migration to the epithelium of the nasal mucosa after intramuscular development

    Directory of Open Access Journals (Sweden)

    Fall E.H.

    2012-11-01

    Full Text Available Knowledge of the biology of the trichinelloid subfamily Trichosomoidinae is poor. Trichosomoides nasalis is a common parasite of Arvicanthis niloticus (Muridae in Senegal, and a procedure for experimental infections has been established. It has been demonstrated that larvae develop in striated muscle fibres, similar to Trichinella spp., but they are not arrested in the first stage, and they reach the adult stage within three weeks. In the present histological study it is shown that T. nasalis females and dwarf males migrate from the abdomen and thorax to the host’s muzzle, moving through connective tissues and between muscles. A few migrating specimens were also found in the blood vessels of the nasal mucosa. While sexes were still separated in the lamina propria of the mucosa, females recovered from the epithelium contained intra-uterine males. Worms were found between the incisors in the mucosa of the anterior and median conchae which are rich in mucous cells. Only the pseudostratified epithelium was parasitized. Under natural conditions, the inflammation of the nasal mucosa that is induced by the parasites might reduce the competitiveness of infected rodents when foraging or looking for potential mates.

  14. Default-mode-like network activation in awake rodents.

    Directory of Open Access Journals (Sweden)

    Jaymin Upadhyay

    Full Text Available During wakefulness and in absence of performing tasks or sensory processing, the default-mode network (DMN, an intrinsic central nervous system (CNS network, is in an active state. Non-human primate and human CNS imaging studies have identified the DMN in these two species. Clinical imaging studies have shown that the pattern of activity within the DMN is often modulated in various disease states (e.g., Alzheimer's, schizophrenia or chronic pain. However, whether the DMN exists in awake rodents has not been characterized. The current data provides evidence that awake rodents also possess 'DMN-like' functional connectivity, but only subsequent to habituation to what is initially a novel magnetic resonance imaging (MRI environment as well as physical restraint. Specifically, the habituation process spanned across four separate scanning sessions (Day 2, 4, 6 and 8. At Day 8, significant (p<0.05 functional connectivity was observed amongst structures such as the anterior cingulate (seed region, retrosplenial, parietal, and hippocampal cortices. Prior to habituation (Day 2, functional connectivity was only detected (p<0.05 amongst CNS structures known to mediate anxiety (i.e., anterior cingulate (seed region, posterior hypothalamic area, amygdala and parabracial nucleus. In relating functional connectivity between cingulate-default-mode and cingulate-anxiety structures across Days 2-8, a significant inverse relationship (r = -0.65, p = 0.0004 was observed between these two functional interactions such that increased cingulate-DMN connectivity corresponded to decreased cingulate anxiety network connectivity. This investigation demonstrates that the cingulate is an important component of both the rodent DMN-like and anxiety networks.

  15. Neurogenic inflammation in human and rodent skin

    DEFF Research Database (Denmark)

    Schmelz, M; Petersen, Lars Jelstrup

    2001-01-01

    The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge...... about neurogenic inflammation in human skin, including the involvement of mast cells.......The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge...

  16. Vibrational communication of subterranean rodents

    OpenAIRE

    HROUZKOVÁ, Ema

    2012-01-01

    This PhD. thesis focuses on the vibrational communication of subterranean mammals, in particular, vocal communication of bathyergids (Heliophobius argenteocinereus, Fukomys mechowii, Fukomys darlingi) and seismic communication of Tachyoryctes. We recorded and analyzed the vocalization of three species and discussed the physical parameters of their vocalization in relationship to the special underground acoustic environment. Moreover, social systems of African mole-rats range from solitary to ...

  17. Parasite diversity of disease-bearing rodents of Southeast Asia: habitat determinants and effects on sexual size dimorphism and life-traits

    Directory of Open Access Journals (Sweden)

    Serge eMorand

    2015-10-01

    Full Text Available We investigated a causal chain of relationships between habitat specialization and parasite species richness in rodent communities in Southeast Asia, and the consequences for variation in immune investment (using spleen size, the degree of sexual competition (using testes and sexual size dimorphism (SSD. We used data gathered on rodents, their habitat specialization and their parasites (macro- and micro-parasites in Southeast Asian landscapes. The results supported the hypotheses that parasite diversity drives the evolution of host life-traits and sexual selection. Firstly host habitat specialization explained the variation in parasite species richness. Secondly high parasite species richness was linked to host immune investment, using the relative spleen size of rodents. Thirdly according to the potential costs associated with immune investment, the relative spleen size was found to be negatively correlated with the relative size of testes among rodents. Fourthly, a positive relationship between male-biased SSD and parasite species richness was observed supporting the role of parasitism in sexual selection. Finally, the variation in SSD was positively associated with the degree of habitat specialization. Highest values of female-biased SSD were associated with habitat specialization, whereas highest values of male-biased SSD concerned synanthropic or generalist rodent species. These results, also correlative, will help to facilitate selection of the species that should be thoroughly investigated at the population level to better understand the selective effects of parasites on rodent life-history and behavior.

  18. The yield and nutritional value of meat from African ungulates, camelidae, rodents, ratites and reptiles.

    Science.gov (United States)

    Hoffman, L C

    2008-09-01

    The current knowledge of the yield and nutritional (proximate and fatty acid) composition of meat derived from African ungulates, camelidae, rodents, ratites and reptiles is reviewed. Although most of the species discussed give low cholesterol levels consistent with their low meat lipid contents, the tegu lizard gives a very low level (18.2mg/100g tissue). The fatty acid profiles of the various species all have low saturated fatty acids and high polyunsaturated fatty acids resulting in favourable saturated to polyunsaturated fatty acid ratios. Although the springbok, camel, ostrich and crocodile are marketed and exported to sophisticated markets, the rodents are the species that show most promise in becoming large commercial commodities. Not only is their meat desirable and nutritional, but they are also highly adaptable to extensive and intensive production systems.

  19. The Need for Speed in Rodent Locomotion Analyses

    Science.gov (United States)

    Batka, Richard J.; Brown, Todd J.; Mcmillan, Kathryn P.; Meadows, Rena M.; Jones, Kathryn J.; Haulcomb, Melissa M.

    2016-01-01

    Locomotion analysis is now widely used across many animal species to understand the motor defects in disease, functional recovery following neural injury, and the effectiveness of various treatments. More recently, rodent locomotion analysis has become an increasingly popular method in a diverse range of research. Speed is an inseparable aspect of locomotion that is still not fully understood, and its effects are often not properly incorporated while analyzing data. In this hybrid manuscript, we accomplish three things: (1) review the interaction between speed and locomotion variables in rodent studies, (2) comprehensively analyze the relationship between speed and 162 locomotion variables in a group of 16 wild-type mice using the CatWalk gait analysis system, and (3) develop and test a statistical method in which locomotion variables are analyzed and reported in the context of speed. Notable results include the following: (1) over 90% of variables, reported by CatWalk, were dependent on speed with an average R2 value of 0.624, (2) most variables were related to speed in a nonlinear manner, (3) current methods of controlling for speed are insufficient, and (4) the linear mixed model is an appropriate and effective statistical method for locomotion analyses that is inclusive of speed-dependent relationships. Given the pervasive dependency of locomotion variables on speed, we maintain that valid conclusions from locomotion analyses cannot be made unless they are analyzed and reported within the context of speed. PMID:24890845

  20. Holocene vegetation history from fossil rodent middens near Arequipa, Peru

    Science.gov (United States)

    Holmgren, C.A.; Betancourt, J.L.; Rylander, K.A.; Roque, J.; Tovar, O.; Zeballos, H.; Linares, E.; Quade, Jay

    2001-01-01

    Rodent (Abrocoma, Lagidium, Phyllotis) middens collected from 2350 to 2750 m elevation near Arequipa, Peru (16??S), provide an ???9600-yr vegetation history of the northern Atacama Desert, based on identification of >50 species of plant macrofossils. These midden floras show considerable stability throughout the Holocene, with slightly more mesophytic plant assemblages in the middle Holocene. Unlike the southwestern United States, rodent middens of mid-Holocene age are common. In the Arequipa area, the midden record does not reflect any effects of a mid-Holocene mega drought proposed from the extreme lowstand (100 m below modern levels, >6000 to 3500 yr B.P.) of Lake Titicaca, only 200 km east of Arequipa. This is perhaps not surprising, given other evidence for wetter summers on the Pacific slope of the Andes during the middle Holocene as well as the poor correlation of summer rainfall among modern weather stations in the central AndesAtacama Desert. The apparent difference in paleoclimatic reconstructions suggests that it is premature to relate changes observed during the Holocene to changes in El Nin??o Southern Oscillation modes. ?? 2001 University of Washington.

  1. Survey for hantaviruses, tick-borne encephalitis virus, and Rickettsia spp. in small rodents in Croatia.

    Science.gov (United States)

    Svoboda, Petra; Dobler, Gerhard; Markotić, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinović, Lidija Cvetko; Tadin, Ante; Margaletić, Josip; Essbauer, Sandra

    2014-07-01

    In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunofluorescence assays (IIFT) and for nucleic acids by conventional (hantaviruses) and real-time RT-/PCRs (TBEV and Rickettsia spp.). A total of 25.5% (24/94) of the rodents from the mountainous area revealed specific antibodies against hantaviruses. In all, 21.3% (20/94) of the samples from the mountainous area and 29.0% (9/31) from the lowland area yielded positive results for either Puumala virus (PUUV) or Dobrava-Belgrade virus (DOBV) using a conventional RT-PCR. All processed samples (n=194) were negative for TBEV by IIFT or real-time RT-PCR. Serological evidence of rickettsial infection was detected in 4.3% (4/94) rodents from the mountainous region. Another 3.2% (3/94) rodents were positive for Rickettsia spp. by real-time PCR. None of the rodents (n=76) from the lowland area were positive for Rickettsia spp. by real-time PCR. Dual infection of PUUV and Rickettsia spp. was found in one M. glareolus from the mountainous area by RT-PCR and real-time PCR, respectively. To our knowledge, this is the first detection of Rickettsia spp. in small rodents from Croatia. Phylogenetic analyses of S- and M-segment sequences obtained from the two study sites revealed well-supported subgroups in Croatian PUUV and DOBV. Although somewhat limited, our data showed occurrence and prevalence of PUUV, DOBV, and rickettsiae in Croatia. Further studies are warranted to confirm these data and to determine the Rickettsia species present in rodents in these areas.

  2. Endocarp thickness affects seed removal speed by small rodents in a warm-temperate broad-leafed deciduous forest, China

    Science.gov (United States)

    Zhang, Hongmao; Zhang, Zhibin

    2008-11-01

    Seed traits are important factors affecting seed predation by rodents and thereby the success of recruitment. Seeds of many tree species have hard hulls. These are thought to confer mechanical protection, but the effect of endocarp thickness on seed predation by rodents has not been well investigated. Wild apricot ( Prunus armeniaca), wild peach ( Amygdalus davidiana), cultivated walnut ( Juglans regia), wild walnut ( Juglans mandshurica Maxim) and Liaodong oak ( Quercus liaotungensis) are very common tree species in northwestern Beijing city, China. Their seeds vary greatly in size, endocarp thickness, caloric value and tannin content. This paper aims to study the effects of seed traits on seed removal speed of these five tree species by small rodents in a temperate deciduous forest, with emphasis on the effect of endocarp thickness. The results indicated that speed of removal of seeds released at stations in the field decreased significantly with increasing endocarp thickness. We found no significant correlations between seed removal speed and other seed traits such as seed size, caloric value and tannin content. In seed selection experiments in small cages, Père David's rock squirrel ( Sciurotamias davidianus), a large-bodied, strong-jawed rodent, selected all of the five seed species, and the selection order among the five seed species was determined by endocarp thickness and the ratio of endocarp mass/seed mass. In contrast, the Korean field mouse ( Apodemus peninsulae) and Chinese white-bellied rat ( Niviventer confucianus), with relatively small bodies and weak jaws, preferred to select small seeds like acorns of Q. liaotungensis and seeds of P. armeniaca, indicating that rodent body size is also an important factor affecting food selection based on seed size. These results suggest endocarp thickness significantly reduces seed removal speed by rodents and then negatively affects dispersal fitness of seeds before seed removal of tree species in the study

  3. Object Recognition Memory and the Rodent Hippocampus

    Science.gov (United States)

    Broadbent, Nicola J.; Gaskin, Stephane; Squire, Larry R.; Clark, Robert E.

    2010-01-01

    In rodents, the novel object recognition task (NOR) has become a benchmark task for assessing recognition memory. Yet, despite its widespread use, a consensus has not developed about which brain structures are important for task performance. We assessed both the anterograde and retrograde effects of hippocampal lesions on performance in the NOR…

  4. BEHAVIOURAL STUDIES ON SOME RHODESIAN RODENTS

    African Journals Online (AJOL)

    behaviour, . courtship, parental and juvenile behaviour and activity patterns. ... behavioural observations were facilitated by the development of a glass-fronted ~'double-storey" cage which ..... Adolescent siblings in both single sex and mixed groups ..... Wild rodents as Laboratory Animals and their contribution to medical.

  5. Rodent malaria parasites : genome organization & comparative genomics

    NARCIS (Netherlands)

    Kooij, Taco W.A.

    2006-01-01

    The aim of the studies described in this thesis was to investigate the genome organization of rodent malaria parasites (RMPs) and compare the organization and gene content of the genomes of RMPs and the human malaria parasite P. falciparum. The release of the complete genome sequence of P.

  6. Rodent movements, densities and radionuclide concentrations at a liquid radioactive waste disposal area

    International Nuclear Information System (INIS)

    Halford, D.K.

    1983-01-01

    Movements and densities of rodents at a liquid radioactive waste disposal area were studied from June to September 1981 using trap line and assessment line techniques. The average distance between points of successive capture was 42 +- 25 (SD) m for deer mice (Peromyscus maniculatus) and 37 +- 21 m for kangaroo rats (Dipodomys ordii). Densities of deer mice averaged 10.2/ha with a population estimate of 57 within the area of rodent captures. The population estimate of 4 species of small mammals at the waste pond complex was 93. Radionuclide concentrations averaged 133 +- 97 pCi/g for rodents captured inside the disposal area boundary, 18 +- 22 pCi/g for those captured outside of the dispoal area fence and 0.50 +- 0.6 pCi/g for control animals. Species captured outside of the waste area boundary had significantly lower (P 137 Cs, 134 Cs, 60 Co and 65 Zn) in rodents at the liquid waste disposal area was estimated to be about 162 nCi

  7. Transformation of the rodent malaria parasite Plasmodium chabaudi.

    Science.gov (United States)

    Spence, Philip J; Cunningham, Deirdre; Jarra, William; Lawton, Jennifer; Langhorne, Jean; Thompson, Joanne

    2011-04-01

    The rodent malaria parasite Plasmodium chabaudi chabaudi shares many features with human malaria species, including P. falciparum, and is the in vivo model of choice for many aspects of malaria research in the mammalian host, from sequestration of parasitized erythrocytes, to antigenic variation and host immunity and immunopathology. This protocol describes an optimized method for the transformation of mature blood-stage P.c. chabaudi and a description of a vector that targets efficient, single crossover integration into the P.c. chabaudi genome. Transformed lines are reproducibly generated and selected within 14-20 d, and show stable long-term protein expression even in the absence of drug selection. This protocol, therefore, provides the scientific community with a robust and reproducible method to generate transformed P.c. chabaudi parasites expressing fluorescent, bioluminescent and model antigens that can be used in vivo to dissect many of the fundamental principles of malaria infection.

  8. Nonhuman gamblers: lessons from rodents, primates, and robots

    Directory of Open Access Journals (Sweden)

    Fabio ePaglieri

    2014-02-01

    Full Text Available The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offer valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics, to make the case for a greater degree of methodological integration in future studies on pathological gambling.

  9. Central melanopsin projections in the diurnal rodent, Arvicanthis niloticus

    Directory of Open Access Journals (Sweden)

    Jennifer Lou Langel

    2015-07-01

    Full Text Available The direct effects of photic stimuli on behavior are very different in diurnal and nocturnal species, as light stimulates an increase in activity in the former and a decrease in the latter. Studies of nocturnal mice have implicated a select population of retinal ganglion cells that are intrinsically photosensitive (ipRGCs in mediation of these acute responses to light. ipRGCs are photosensitive due to the expression of the photopigment melanopsin; these cells use glutamate and pituitary adenylate cyclase-activating polypeptide (PACAP as neurotransmitters. PACAP is useful for the study of central ipRGC projections because, in the retina, it is found exclusively within melanopsin cells. Little is known about the central projections of ipRGCs in diurnal species. Here, we first characterized these cells in the retina of the diurnal Nile grass rat using immunohistochemistry (IHC. The same basic subtypes of melanopsin cells that have been described in other mammals were present, but nearly 25% of them were displaced, primarily in its superior region. PACAP was present in 87.7% of all melanopsin cells, while 97.4% of PACAP cells contained melanopsin. We then investigated central projections of ipRGCs by examining the distribution of immunoreactive PACAP fibers in intact and enucleated animals. This revealed evidence that these cells project to the suprachiasmatic nucleus, lateral geniculate nucleus (LGN, pretectum and superior colliculus. This distribution was confirmed with injections of cholera toxin subunit β coupled with Alexa Fluor 488 in one eye and Alexa Flour 594 in the other, combined with IHC staining of PACAP. These studies also revealed that the ventral and dorsal LGN and the caudal olivary pretectal nucleus receive less innervation from ipRGCs than that reported in nocturnal rodents. Overall, these data suggest that although ipRGCs and their projections are very similar in diurnal and nocturnal rodents, they may not be identical.

  10. Arctic Small Rodents Have Diverse Diets and Flexible Food Selection.

    Directory of Open Access Journals (Sweden)

    Eeva M Soininen

    Full Text Available The ecology of small rodent food selection is poorly understood, as mammalian herbivore food selection theory has mainly been developed by studying ungulates. Especially, the effect of food availability on food selection in natural habitats where a range of food items are available is unknown. We studied diets and selectivity of grey-sided voles (Myodes rufocanus and tundra voles (Microtus oeconomus, key herbivores in European tundra ecosystems, using DNA metabarcoding, a novel method enabling taxonomically detailed diet studies. In order to cover the range of food availabilities present in the wild, we employed a large-scale study design for sampling data on food availability and vole diets. Both vole species had ingested a range of plant species and selected particularly forbs and grasses. Grey-sided voles also selected ericoid shrubs and tundra voles willows. Availability of a food item rarely affected its utilization directly, although seasonal changes of diets and selection suggest that these are positively correlated with availability. Moreover, diets and selectivity were affected by availability of alternative food items. These results show that the focal sub-arctic voles have diverse diets and flexible food preferences and rarely compensate low availability of a food item with increased searching effort. Diet diversity itself is likely to be an important trait and has previously been underrated owing to methodological constraints. We suggest that the roles of alternative food item availability and search time limitations for small rodent feeding ecology should be investigated.Annotated Checklist of the Panarctic Flora (PAF, Vascular plants. Available at: http://nhm2.uio.no/paf/, accessed 15.6.2012.

  11. Assessment of Trace Metals in Soil, Vegetation and Rodents in Relation to Metal Mining Activities in an Arid Environment.

    Science.gov (United States)

    Méndez-Rodríguez, Lia C; Alvarez-Castañeda, Sergio Ticul

    2016-07-01

    Areas where abandoned metal-extraction mines are located contain large quantities of mineral wastes derived from environmentally unsafe mining practices. These wastes contain many pollutants, such as heavy metals, which could be released to the environment through weathering and leaching, hence becoming an important source of environmental metal pollution. This study evaluates differences in the levels of lead, iron, nickel, manganese, copper and cadmium in rodents sharing the same type of diet under different microhabitat use in arid areas with past mining activities. Samples of soil, roots, branches and seeds of Palo Adán (Fouquieria diguetii) and specimens of two rodent species (Chaetodipus arenarius and C. spinatus) were collected in areas with impact from past metal mining activities as well as from areas with no mining impact. Both rodent species mirrored nickel and iron levels in soil and seeds, as well as lead levels in soil; however, C. arenarius accumulated higher levels of manganese, copper and cadmium.

  12. Fruit Size Determines the Role of Three Scatter-Hoarding Rodents as Dispersers or Seed Predators of a Fleshy-Fruited Atacama Desert Shrub

    Science.gov (United States)

    Loayza, Andrea P.; Squeo, Francisco A.

    2016-01-01

    Scatter-hoarding rodents can act as both predators and dispersers for many large-seeded plants because they cache seeds for future use, but occasionally forget them in sites with high survival and establishment probabilities. The most important fruit or seed trait influencing rodent foraging behavior is seed size; rodents prefer large seeds because they have higher nutritional content, but this preference can be counterbalanced by the higher costs of handling larger seeds. We designed a cafeteria experiment to assess whether fruit and seed size of Myrcianthes coquimbensis, an endangered desert shrub, influence the decision-making process during foraging by three species of scatter-hoarding rodents differing in body size: Abrothrix olivaceus, Phyllotis darwini and Octodon degus. We found that the size of fruits and seeds influenced foraging behavior in the three rodent species; the probability of a fruit being harvested and hoarded was higher for larger fruits than for smaller ones. Patterns of fruit size preference were not affected by rodent size; all species were able to hoard fruits within the entire range of sizes offered. Finally, fruit and seed size had no effect on the probability of seed predation, rodents typically ate only the fleshy pulp of the fruits offered and discarded whole, intact seeds. In conclusion, our results reveal that larger M. coquimbensis fruits have higher probabilities of being harvested, and ultimately of its seeds being hoarded and dispersed by scatter-hoarding rodents. As this plant has no other dispersers, rodents play an important role in its recruitment dynamics. PMID:27861550

  13. Homeobox Genes in the Rodent Pineal Gland

    DEFF Research Database (Denmark)

    Rath, Martin Fredensborg; Rohde, Kristian; Klein, David C

    2013-01-01

    The pineal gland is a neuroendocrine gland responsible for nocturnal synthesis of melatonin. During early development of the rodent pineal gland from the roof of the diencephalon, homeobox genes of the orthodenticle homeobox (Otx)- and paired box (Pax)-families are expressed and are essential...... for normal pineal development consistent with the well-established role that homeobox genes play in developmental processes. However, the pineal gland appears to be unusual because strong homeobox gene expression persists in the pineal gland of the adult brain. Accordingly, in addition to developmental...... functions, homeobox genes appear to be key regulators in postnatal phenotype maintenance in this tissue. In this paper, we review ontogenetic and phylogenetic aspects of pineal development and recent progress in understanding the involvement of homebox genes in rodent pineal development and adult function...

  14. Effects of anatomy and diet on gastrointestinal pH in rodents.

    Science.gov (United States)

    Kohl, Kevin D; Stengel, Ashley; Samuni-Blank, Michal; Dearing, M Denise

    2013-04-01

    The pH of the gastrointestinal tract can have profound influences on digestive processes. Rodents exhibit wide variation in both stomach morphology and dietary strategies, both of which may influence gut pH. Various rodent species have evolved bilocular (or semi-segmented) stomachs that may allow for more microbial growth compared to unilocular (single-chambered) stomachs. Additionally, herbivory has evolved multiple times in rodents. The high dietary fiber typical of an herbivorous diet is known to induce secretion of bicarbonate in the gut. We predicted that stomach segmentation might facilitate the separation of contents in the proximal chamber from that of the gastric stomach, facilitating a chemical environment suitable to microbial growth. To investigate the effect of stomach anatomy and diet on gut pH, several species of rodent with varying stomach morphology were fed either a high or low-fiber diet for 7 days, and pH of the proximal stomach, gastric stomach, small intestine, and cecum were measured. We discovered that rodents with bilocular stomach anatomy maintained a larger pH gradient between the proximal and gastric stomach compartments, and were able to achieve a lower absolute gastric pH compared to those with unilocular stomachs. Dietary fiber increased the pH of the small intestine, but not in any other gut regions. The stomach pH data supports the century old hypothesis that bilocular stomach anatomy creates an environment in the proximal stomach that is suitable for microbial growth. Additionally, the alkaline small intestinal pH on a high fiber diet may enhance digestion. Copyright © 2013 Wiley Periodicals, Inc.

  15. Ecology, genetic diversity, and phylogeographic structure of andes virus in humans and rodents in Chile.

    Science.gov (United States)

    Medina, Rafael A; Torres-Perez, Fernando; Galeno, Hector; Navarrete, Maritza; Vial, Pablo A; Palma, R Eduardo; Ferres, Marcela; Cook, Joseph A; Hjelle, Brian

    2009-03-01

    Andes virus (ANDV) is the predominant etiologic agent of hantavirus cardiopulmonary syndrome (HCPS) in southern South America. In Chile, serologically confirmed human hantavirus infections have occurred throughout a wide latitudinal distribution extending from the regions of Valparaíso (32 to 33 degrees S) to Aysén (46 degrees S) in southern Patagonia. In this study, we found seropositive rodents further north in the Coquimbo region (30 degrees S) in Chile. Rodent seroprevalence was 1.4%, with Oligoryzomys longicaudatus displaying the highest seroprevalence (5.9%), followed by Abrothrix longipilis (1.9%) and other species exhibiting Chile. Phylogenetic analyses showed two major ANDV South (ANDV Sout) clades, congruent with two major Chilean ecoregions, Mediterranean (Chilean matorral [shrubland]) and Valdivian temperate forest. Human and rodent samples grouped according to geographic location. Phylogenetic comparative analyses of portions of S and medium segments (encoding glycoproteins Gn and Gc) from a subset of rodent specimens exhibited similar topologies, corroborating two major ANDV Sout clades in Chile and suggesting that yet unknown factors influence viral gene flow and persistence throughout the two Chilean ecoregions. Genetic algorithms for recombination detection identified recombination events within the S segment. Molecular demographic analyses showed that the virus is undergoing purifying selection and demonstrated a recent exponential growth in the effective number of ANDV Sout infections in Chile that correlates with the increased number of human cases reported. Although we determined virus sequences from four rodent species, our results confirmed O. longicaudatus as the primary ANDV Sout reservoir in Chile. While evidence of geographic differentiation exists, a single cosmopolitan lineage of ANDV Sout remains the sole etiologic agent for HCPS in Chile.

  16. Rodent Plasmodium-infected red blood cells: imaging their fates and interactions within their hosts.

    Science.gov (United States)

    Claser, Carla; Malleret, Benoit; Peng, Kaitian; Bakocevic, Nadja; Gun, Sin Yee; Russell, Bruce; Ng, Lai Guan; Rénia, Laurent

    2014-02-01

    Malaria, a disease caused by the Plasmodium parasite, remains one of the most deadly infectious diseases known to mankind. The parasite has a complex life cycle, of which only the erythrocytic stage is responsible for the diverse pathologies induced during infection. To date, the disease mechanisms that underlie these pathologies are still poorly understood. In the case of infections caused by Plasmodium falciparum, the species responsible for most malaria related deaths, pathogenesis is thought to be due to the sequestration of infected red blood cells (IRBCs) in deep tissues. Other human and rodent malaria parasite species are also known to exhibit sequestration. Here, we review the different techniques that allow researchers to study how rodent malaria parasites modify their host cells, the distribution of IRBCs in vivo as well as the interactions between IRBCs and host tissues. © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  17. Comparative Evaluation of Permissiveness to Dengue Virus Serotype 2 Infection in Primary Rodent Macrophages

    Directory of Open Access Journals (Sweden)

    Jeanette Prada-Arismendy

    2012-01-01

    Full Text Available Infection with dengue virus presents a broad clinical spectrum, which can range from asymptomatic cases to severe cases that are characterised by haemorrhagic syndrome and/or shock. The reason for such variability remains unknown. This work evaluated the in vitro permissiveness of mouse, rat, hamster and guinea pig macrophages to infection by dengue virus 2 (DENV2. The results established that macrophages derived from the BALB/c mouse strain showed higher permissiveness to DENV2 infection than macrophages from other rodent species, although all rodent species studied had the C820T mutation in the oligoadenylate synthetase 1b gene, indicating no relationship to the different in vitro susceptibilities of mouse cells at this locus. Other molecular mechanisms related to flavivirus susceptibility remain to be explored.

  18. Expensive Brains: “Brainy” Rodents have Higher Metabolic Rate

    Science.gov (United States)

    Sobrero, Raúl; May-Collado, Laura J.; Agnarsson, Ingi; Hernández, Cristián E.

    2011-01-01

    Brains are the centers of the nervous system of animals, controlling the organ systems of the body and coordinating responses to changes in the ecological and social environment. The evolution of traits that correlate with cognitive ability, such as relative brain size is thus of broad interest. Brain mass relative to body mass (BM) varies among mammals, and diverse factors have been proposed to explain this variation. A recent study provided evidence that energetics play an important role in brain evolution (Isler and van Schaik, 2006). Using composite phylogenies and data drawn from multiple sources, these authors showed that basal metabolic rate (BMR) correlates with brain mass across mammals. However, no such relationship was found within rodents. Here we re-examined the relationship between BMR and brain mass within Rodentia using a novel species-level phylogeny. Our results are sensitive to parameter evaluation; in particular how species mass is estimated. We detect no pattern when applying an approach used by previous studies, where each species BM is represented by two different numbers, one being the individual that happened to be used for BMR estimates of that species. However, this approach may compromise the analysis. When using a single value of BM for each species, whether representing a single individual, or available species mean, our findings provide evidence that brain mass (independent of BM) and BMR are correlated. These findings are thus consistent with the hypothesis that large brains evolve when the payoff for increased brain mass is greater than the energetic cost they incur. PMID:21811456

  19. Ectoparasites of livestock, dogs, and wild rodents in the Chittagong Hill Tracts in southeastern Bangladesh.

    Science.gov (United States)

    Fuehrer, Hans-Peter; Igel, Petra; Treiber, Moritz; Baumann, Timo A; Riedl, Julia; Swoboda, Paul; Joachim, Anja; Noedl, Harald

    2012-10-01

    A large variety of ectoparasites parasitizing on livestock, dogs, and rodents are documented throughout the world, of which several are proven vectors for major (including zoonotic) diseases affecting humans and/or livestock. However, there remains a significant lack of knowledge in regard to the ectoparasite fauna in remote regions of the developing world, such as southeastern Bangladesh, and an urgent need to investigate this fauna to improve diagnostic options. In the course of the present study, more than 5,300 ectoparasites were collected by flag dragging and handpicking of livestock, dogs, and rodents in the District of Bandarban (Chittagong Hill Tracts) in southeastern Bangladesh. Three tick species were identified: Haemaphysalis bispinosa (flagging, cattle, goats, and dogs), Rhipicephalus microplus (cattle, goats), and Rhipicephalus sanguineus (dogs, goats, and flagging). H. bispinosa was the dominant tick species on mammalian hosts as well as on vegetation. Furthermore, Ctenocephalides canis (dogs, goats) and Linognatus sp. (goat) were found. Overall, 73 rodents of eight different species (e.g., Mus musculus, Rattus sikkimensis, Bandicota bengalensis, and Niviventer sp.) hosted a variety of ectoparasites such as mites (Laelaps nuttali, Laelaps echidninus, Lyponissoides sp. and Ornithonyssus bacoti), fleas (Xenopsylla cheopis), and one myiasis-causing dipteran species. Monitoring the ectoparasite burden of livestock and other mammals is urgently needed in order to control ectoparasites associated with social and economic burden (e.g., reduced milk production, weight loss). Several zoonotic diseases can be transmitted by ectoparasites in this area, where the majority of the population live in basic housing conditions and in direct contact with livestock, dogs, and rodents.

  20. Evolutionary history of the most speciose mammals: molecular phylogeny of muroid rodents.

    OpenAIRE

    Michaux, Johan; Reyes, A.; Catzeflis, F.

    2001-01-01

    Phylogenetic relationships between 32 species of rodents representing 14 subfamilies of Muridae and four subfamilies of Dipodidae were studied using sequences of the nuclear protein-coding genes Lecithin Cholesterol Acyl Transferase (LCAT) and von Willebrand Factor (vWF). An examination of some evolutionary properties of each data matrix indicates that the two genes are rather complementary, with lower rates of nonsynonymous substitutions for LCAT. Both markers exhibit a wide range of GC3 per...

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Gastrointestinal parasites in feral cats and rodents from the Fernando de Noronha Archipelago, Brazil

    Directory of Open Access Journals (Sweden)

    Victor Fernando Santana Lima

    2017-11-01

    Full Text Available Abstract Gastrointestinal parasites are important pathogens affecting animals, some of them are of medical and veterinary concern. Although the dynamic of parasitic infections is a complex phenomenon that has been studied under experimental conditions, it shows several gaps in knowledge, especially in insular regions where a confined population of animals and parasites co-exists. In this study was assessed the parasitism by endoparasite gastrointestinal in feral cats (n = 37 and rodents (n = 30 from the Fernando de Noronha Archipelago; in addition, the risk of human infection and ecological implications of these findings were discussed. Out of all samples analysed, 100% scored positive for the presence of gastrointestinal parasites in both feral cats and rodents. A total 17 genera and/or species of endoparasite gastrointestinal were identified, Ancylostoma sp., Strongyloides sp., Trichuris campanula and Toxocara cati were the parasites more frequently in feral cats. In rodents Eimeria sp., Strongyloides sp. and Trichuris muris were parasites more frequently herein detected. Human population living in this area are at risk of parasite infections due to the population of rodents and feral cats in the archipelago.

  3. Muleshoe Virus and Other Hantaviruses Associated with Neotomine or Sigmodontine Rodents in Texas.

    Science.gov (United States)

    Milazzo, Mary Louise; Cajimat, Maria N B; Richter, Martin H; Bradley, Robert D; Fulhorst, Charles F

    2017-10-01

    The broad objective of this study was to increase our knowledge of Muleshoe virus and other hantaviruses associated with cricetid rodents in Texas. Anti-hantavirus antibody was found in 38 (3.2%) of 1171 neotomine rodents and 6 (1.8%) of 332 sigmodontine rodents from 10 Texas counties; hantaviral RNA was detected in 23 (71.9%) of 32 antibody-positive rodents. Analyses of nucleocapsid protein gene sequences indicated Muleshoe virus infection in four hispid cotton rats (Sigmodon hispidus) from northern Texas; Bayou virus, three Texas marsh oryzomys (Oryzomys texensis) from the Gulf Coast; Limestone Canyon virus, five brush mice (Peromyscus boylii) from western Texas; and Sin Nombre virus-five Texas mice (P. attwateri), one Lacey's white-ankled deer mouse (P. laceianus), four white-footed mice (P. leucopus), and one fulvous harvest mouse (Reithrodontomys fulvescens) from northern, central, or southern Texas. The results of this study together with the results of a previous study revealed that Muleshoe virus, perhaps in association with S. hispidus, is distributed across northern Texas. Finally, the results of Bayesian analyses of glycoprotein precursor (GPC) gene sequences and pairwise comparisons of complete GPC (amino acid) sequences strengthened support for the notion that Muleshoe virus is distinct from Black Creek Canal virus, Bayou virus, and all other species included in the Bunyaviridae, genus Hantavirus.

  4. Gastrointestinal parasites in feral cats and rodents from the Fernando de Noronha Archipelago, Brazil.

    Science.gov (United States)

    Lima, Victor Fernando Santana; Ramos, Rafael Antonio Nascimento; Lepold, Raphael; Borges, João Carlos Gomes; Ferreira, Carlos Diógenes; Rinaldi, Laura; Cringoli, Giuseppe; Alves, Leucio Câmara

    2017-01-01

    Gastrointestinal parasites are important pathogens affecting animals, some of them are of medical and veterinary concern. Although the dynamic of parasitic infections is a complex phenomenon that has been studied under experimental conditions, it shows several gaps in knowledge, especially in insular regions where a confined population of animals and parasites co-exists. In this study was assessed the parasitism by endoparasite gastrointestinal in feral cats (n = 37) and rodents (n = 30) from the Fernando de Noronha Archipelago; in addition, the risk of human infection and ecological implications of these findings were discussed. Out of all samples analysed, 100% scored positive for the presence of gastrointestinal parasites in both feral cats and rodents. A total 17 genera and/or species of endoparasite gastrointestinal were identified, Ancylostoma sp., Strongyloides sp., Trichuris campanula and Toxocara cati were the parasites more frequently in feral cats. In rodents Eimeria sp., Strongyloides sp. and Trichuris muris were parasites more frequently herein detected. Human population living in this area are at risk of parasite infections due to the population of rodents and feral cats in the archipelago.

  5. Known from a handful of specimens: analyzing the worldwide patterns of occurrence and conservation of rodents and shrews recorded only from the type locality

    Directory of Open Access Journals (Sweden)

    Giovanni Amori

    2016-03-01

    Full Text Available Traditionally, conservation research has not focused on Rodentia and Soricomorpha, and many species are known from a handful of specimens and the type locality only (few and type locality species (FETP.  Here we studied the patterns of occurrence of FETP rodents and soricomorphs in relation to geographical area and vegetation zones and report some conservation considerations.  Overall, 91 species of Rodentia and 19 species of Soricomorpha were selected.  There was a positive correlation between number of species per genus and number of FETP species in each genus.  The majority of FETP rodents occur in the Neotropical, Afrotropical and Oriental regions, and soricomorphs in the Afrotropical and Oriental regions. Higher numbers of FETP rodent species occurred in Argentina and Indonesia.  There was a positive relationship between species richness of rodents per country and number of FETP species.  In terms of habitat type, FETP species of rodents and soricomorphs showed similar patterns, with most species being found in rainforest.  The great majority of selected species of both groups were Data Deficient (DD, with Critically Endangered (CR accounting for 16.5% of Rodentia and 5.3% of Soricomorpha.  Overall, IUCN threatened species mostly occur in the Neotropical region, followed by the Afrotropical region.  It is urged that IUCN authorities should promptly revise all FETP species and their precautionary CR status, at least when a reasonable timespan (i.e., >25 years has passed since the last records. 

  6. Isolation and characterization of a novel arenavirus harbored by Rodents and Shrews in Zhejiang province, China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kun [State Key Laboratory for Infectious Disease Prevention and Control, Department of Zoonoses, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing (China); Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou (China); Lin, Xian-Dan [Wenzhou Center for Disease Control and Prevention, Wenzhou, Zhejiang Province (China); Wang, Wen [State Key Laboratory for Infectious Disease Prevention and Control, Department of Zoonoses, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing (China); Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou (China); Shi, Mang [State Key Laboratory for Infectious Disease Prevention and Control, Department of Zoonoses, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing (China); Wencheng Center for Disease Control and Prevention, Wenzhou, Zhejiang Province (China); Guo, Wen-Ping [State Key Laboratory for Infectious Disease Prevention and Control, Department of Zoonoses, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing (China); Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou (China); Zhang, Xiao-He [Wenzhou Center for Disease Control and Prevention, Wenzhou, Zhejiang Province (China); Xing, Jian-Guang [Wencheng Center for Disease Control and Prevention, Wenzhou, Zhejiang Province (China); and others

    2015-02-15

    To determine the biodiversity of arenaviruses in China, we captured and screened rodents and shrews in Wenzhou city, Zhejiang province, a locality where hemorrhagic fever diseases are endemic in humans. Accordingly, arenaviruses were detected in 42 of 351 rodents from eight species, and in 12 of 272 Asian house shrews (Suncus murinus), by RT-PCR targeting the L segment. From these, a single arenavirus was successfully isolated in cell culture. The virion particles exhibited a typical arenavirus morphology under transmission electron microscopy. Comparison of the S and L segment sequences revealed high levels of nucleotide (>32.2% and >39.6%) and amino acid (>28.8% and >43.8%) sequence differences from known arenaviruses, suggesting that it represents a novel arenavirus, which we designated Wenzhou virus (WENV). Phylogenetic analysis revealed that all WENV strains harbored by both rodents and Asian house shrews formed a distinct lineage most closely related to Old World arenaviruses. - Highlights: • A novel arenavirus (Wenzhou virus) was identified in Zhejiang province, China. • The virus is highly circulating in five species of rats and one species of shrews • More efforts are needed to infer whether it is pathogenic to humans or not.

  7. Visual pigment coexpression in all cones of two rodents, the Siberian hamster, and the pouched mouse.

    Science.gov (United States)

    Lukáts, Akos; Dkhissi-Benyahya, Ouria; Szepessy, Zsuzsanna; Röhlich, Pál; Vígh, Béla; Bennett, Nigel C; Cooper, Howard M; Szél, Agoston

    2002-07-01

    To decide whether the identical topography of short- and middle-wavelength cone photoreceptors in two species of rodents reflects the presence of both opsins in all cone cells. Double-label immunocytochemistry using antibodies directed against short-wavelength (S)-and middle- to long-wavelength (M/L)-sensitive opsin were used to determine the presence of visual pigments in cones of two species of rodents, the Siberian hamster (Phodopus sungorus) and the pouched mouse (Saccostomus campestris) from South Africa. Topographical distribution was determined from retinal whole-mounts, and the colocalization of visual pigments was examined using confocal laser scanning microscopy. Opsin colocalization was also confirmed in consecutive semithin tangential sections. The immunocytochemical results demonstrate that in both the Siberian hamster and the pouched mouse all retinal cones contain two visual pigments. No dorsoventral gradient in the differential expression of the two opsins is observed. The retina of the Siberian hamster and the pouched mouse is the first example to show a uniform coexpression of M and S cone opsins in all cones, without any topographical gradient in opsin expression. This finding makes these two species good models for the study of molecular control mechanisms in opsin coexpression in rodents, and renders them suitable as sources of dual cones for future investigations on the role and neural connections of this cone type.

  8. Isolation and characterization of a novel arenavirus harbored by Rodents and Shrews in Zhejiang province, China

    International Nuclear Information System (INIS)

    Li, Kun; Lin, Xian-Dan; Wang, Wen; Shi, Mang; Guo, Wen-Ping; Zhang, Xiao-He; Xing, Jian-Guang

    2015-01-01

    To determine the biodiversity of arenaviruses in China, we captured and screened rodents and shrews in Wenzhou city, Zhejiang province, a locality where hemorrhagic fever diseases are endemic in humans. Accordingly, arenaviruses were detected in 42 of 351 rodents from eight species, and in 12 of 272 Asian house shrews (Suncus murinus), by RT-PCR targeting the L segment. From these, a single arenavirus was successfully isolated in cell culture. The virion particles exhibited a typical arenavirus morphology under transmission electron microscopy. Comparison of the S and L segment sequences revealed high levels of nucleotide (>32.2% and >39.6%) and amino acid (>28.8% and >43.8%) sequence differences from known arenaviruses, suggesting that it represents a novel arenavirus, which we designated Wenzhou virus (WENV). Phylogenetic analysis revealed that all WENV strains harbored by both rodents and Asian house shrews formed a distinct lineage most closely related to Old World arenaviruses. - Highlights: • A novel arenavirus (Wenzhou virus) was identified in Zhejiang province, China. • The virus is highly circulating in five species of rats and one species of shrews • More efforts are needed to infer whether it is pathogenic to humans or not

  9. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents.

    Science.gov (United States)

    Haitina, Tatjana; Fredriksson, Robert; Foord, Steven M; Schiöth, Helgi B; Gloriam, David E

    2009-01-15

    The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs) is one of the largest gene families in most mammals and the most exploited in terms of drug discovery. An accurate comparison of the GPCR repertoires in dog and human is valuable for the prediction of functional similarities and differences between the species. We searched the dog genome for non-olfactory GPCRs and obtained 353 full-length GPCR gene sequences, 18 incomplete sequences and 13 pseudogenes. We established relationships between human, dog, rat and mouse GPCRs resolving orthologous pairs and species-specific duplicates. We found that 12 dog GPCR genes are missing in humans while 24 human GPCR genes are not part of the dog GPCR repertoire. There is a higher number of orthologous pairs between dog and human that are conserved as compared with either mouse or rat. In almost all cases the differences observed between the dog and human genomes coincide with other variations in the rodent species. Several GPCR gene expansions characteristic for rodents are not found in dog. The repertoire of dog non-olfactory GPCRs is more similar to the repertoire in humans as compared with the one in rodents. The comparison of the dog, human and rodent repertoires revealed several examples of species-specific gene duplications and deletions. This information is useful in the selection of model organisms for pharmacological experiments.

  10. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents

    Directory of Open Access Journals (Sweden)

    Schiöth Helgi B

    2009-01-01

    Full Text Available Abstract Background The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs is one of the largest gene families in most mammals and the most exploited in terms of drug discovery. An accurate comparison of the GPCR repertoires in dog and human is valuable for the prediction of functional similarities and differences between the species. Results We searched the dog genome for non-olfactory GPCRs and obtained 353 full-length GPCR gene sequences, 18 incomplete sequences and 13 pseudogenes. We established relationships between human, dog, rat and mouse GPCRs resolving orthologous pairs and species-specific duplicates. We found that 12 dog GPCR genes are missing in humans while 24 human GPCR genes are not part of the dog GPCR repertoire. There is a higher number of orthologous pairs between dog and human that are conserved as compared with either mouse or rat. In almost all cases the differences observed between the dog and human genomes coincide with other variations in the rodent species. Several GPCR gene expansions characteristic for rodents are not found in dog. Conclusion The repertoire of dog non-olfactory GPCRs is more similar to the repertoire in humans as compared with the one in rodents. The comparison of the dog, human and rodent repertoires revealed several examples of species-specific gene duplications and deletions. This information is useful in the selection of model organisms for pharmacological experiments.

  11. Neospora caninum and Toxoplasma gondii in brain tissue of feral rodents and insectivores caught on farms in the Netherlands

    NARCIS (Netherlands)

    Meerburg, B.G.; Craeye, de S.; Dierick, K.; Kijlstra, A.

    2012-01-01

    We investigated the presence of both Neospora caninum and Toxoplasma gondii in 250 brain tissue samples from 9 species of feral rodents and insectivores caught on 10 organic farms in the Netherlands in 2004. Collected samples were conserved in 4% paraformaldehyde solution and analysed by real-time

  12. A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. III. Heavy Water and Constant Light : Homeostasis of Frequency?

    NARCIS (Netherlands)

    Daan, Serge; Pittendrigh, Colin S.

    1976-01-01

    1. In a preceding paper differences in the lability of the freerunning circadian period (τ) in constant darkness (DD) were described among four species of rodents. This lability (i) is strongly correlated with the responses of τ to (ii) D2O-administration and to (iii) constant light (LL) of various

  13. Development of a reliable method for determining sex for a primitive rodent, the Point Arena mountain beaver (Aplodontia rufa nigra)

    Science.gov (United States)

    Kristine L. Pilgrim; William J. Zielinski; Fredrick V. Schlexer; Michael K. Schwartz

    2012-01-01

    The mountain beaver (Aplodontia rufa) is a primitive species of rodent, often considered a living fossil. The Point Arena mountain beaver (Aplodontia rufa nigra) is an endangered subspecies that occurs in a very restricted range in northern California. Efforts to recover this taxon have been limited by the lack of knowledge on their demography, particularly sex and age...

  14. Impact intensity of rodents on the forest regeneration in artificial plantations in the Smrk - Kněhyně area

    Czech Academy of Sciences Publication Activity Database

    Heroldová, Marta; Suchomel, J.; Purchart, L.; Homolka, Miloslav

    2008-01-01

    Roč. 1, č. 1 (2008), s. 33-35 ISSN 1803-2451 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : artificial forest plantations * forest regeneration * herbivorous rodent species Subject RIV: EH - Ecology, Behaviour

  15. Rodent communities in the sub-polar Ural mountains

    Directory of Open Access Journals (Sweden)

    Berdyugin, K. I.

    2004-12-01

    Full Text Available Distribution of the rodent communities in the Sub-polar Urals is analysed. This part of the range, between 64° and 66°N, includes the highest peaks, is very scarcely settled and has been rarely studied. However, the area is interesting for biogeography, being a border zone separating European and Siberian lowland faunas. Comparison of results with those from expeditions undertaken in 1927 and in 1972, allows to evaluate changing trends in the local rodent communities, and to relate these trends to changes in the environmental conditions. The results help to emphasize the barrier role played by Sub-polar Urals for the species of rodents inhabiting both sides of the range, and also show the shifting of southern rodent forms northwards, or the moving upwards of other lowland species. This could be seen as an additional evidence of current climate warming trends.

    [fr]
    On analyse la répartition des communautés de rongeurs dans les Durais Subpolaires, une section de la chaîne comprise entre les 64° et les 66° de latitude N. Cette partie est très peu peuplée, elle possède les pics les plus hauts de la chaîne et a été rarement étudiée. Il s'agit d'une région intéressante, car c'est la frontière entre les plaines européennes et les plaines orientales de la Sibérie. En comparant les observations effectuées en 1927 et en 1972 avec celles des dernières années, on peut voir les tendances de changement des groupements de rongeurs de la région, et les interpréter en fonction des changements dans l'environnement. Les résultats permettent de mieux comprendre le rôle de barrière qui jouent les Durais Subpolaires pour les espèces de rongeurs situées d'un coté et d'autre de la chaîne. Aussi, ils permettent de verifier le déplacement vers le nord deformes méridionales et l'élévation en altitude d'autres, ce qui pourrait être vu comme une preuve additionnelle de la tendance au réchauffement global.
    [es]
    Se

  16. Functional interrogation of Plasmodium genus metabolism identifies species- and stage-specific differences in nutrient essentiality and drug targeting

    KAUST Repository

    Abdel-Haleem, Alyaa M.; Hefzi, Hooman; Mineta, Katsuhiko; Gao, Xin; Gojobori, Takashi; Palsson, Bernhard O.; Lewis, Nathan E.; Jamshidi, Neema

    2018-01-01

    and predicted potential targets that could affect several life cycle stages. The species-specific models further highlight differences between experimental animal models and the human-infecting species. Comparisons between human- and rodent-infecting species

  17. In-Silico detection of chokepoints enzymes in four plasmodium species

    African Journals Online (AJOL)

    Of the over 156 species of Plasmodium that infect vertebrates, only four infect man: Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale and Plasmodium malariae. Other species infect other animals including birds, reptiles and rodents. The rodent malaria parasites are Plasmodium berghei, Plasmodium yoelii, ...

  18. Urban Market Gardening and Rodent-Borne Pathogenic Leptospira in Arid Zones: A Case Study in Niamey, Niger.

    Science.gov (United States)

    Dobigny, Gauthier; Garba, Madougou; Tatard, Caroline; Loiseau, Anne; Galan, Max; Kadaouré, Ibrahima; Rossi, Jean-Pierre; Picardeau, Mathieu; Bertherat, Eric

    2015-01-01

    Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic Leptospira species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, lipL32 gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual Leptospira reservoir rodent species (namely R. rattus and M. natalensis) are yet abundant. On the contrary, L. kirschneri was detected in Arvicanthis niloticus and Cricetomys gambianus, two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings.

  19. Urban Market Gardening and Rodent-Borne Pathogenic Leptospira in Arid Zones: A Case Study in Niamey, Niger.

    Directory of Open Access Journals (Sweden)

    Gauthier Dobigny

    Full Text Available Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic Leptospira species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, lipL32 gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual Leptospira reservoir rodent species (namely R. rattus and M. natalensis are yet abundant. On the contrary, L. kirschneri was detected in Arvicanthis niloticus and Cricetomys gambianus, two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings.

  20. First identification of Echinococcus multilocularis in rodent intermediate hosts in Sweden

    Directory of Open Access Journals (Sweden)

    Andrea L. Miller

    2016-04-01

    Full Text Available Echinococcus multilocularis is a zoonotic tapeworm with a sylvatic lifecycle and an expanding range in Europe. Monitoring efforts following its first identification in 2011 in Sweden have focused on the parasite's definitive host, the red fox (Vulpes vulpes. However, identifying rodent intermediate hosts is important to recognize opportunities for parasite transmission. During 2013–2015, livers from a total of 1566 rodents from four regions in Sweden were examined for E. multilocularis metacestode lesions. Species identity of suspect parasite lesions was confirmed by PCR and sequencing. E. multilocularis positive lesions >6 mm in diameter were also examined histologically. One Microtus agrestis out of 187 (0.5%, 95%CI: 0–2.9%, 8/439 (1.8%, 95%CI: 0.8–3.6% Arvicola amphibius, 0/655 (0%, 95%CI: 0–0.6% Myodes glareolus, and 0/285 (0%, 95%CI: 0–1.3% Apodemus spp. contained E. multilocularis metacestode lesions. Presence of protoscoleces was confirmed in the infected M. agrestis and in three of eight infected A. amphibius. Six of the nine positive rodents were captured from the same field. This is the first report of E. multilocularis in intermediate hosts in Sweden. The cluster of positive rodents in one field shows that local parasite prevalence can be high in Sweden despite overall low national prevalence in foxes (<0.1%. The presence of protoscoleces in infected M. agrestis and A. amphibius indicate these species can serve as competent intermediate hosts in Sweden. However, their relative importance for E. multilocularis transmission in the Swedish environment is not yet possible to assess. In contrast, the negative findings in all M. glareolus and Apodemus spp. suggest that these species are of no importance.

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

    Directory of Open Access Journals (Sweden)

    M. Fernanda López Berrizbeitia

    2017-06-01

    Full Text Available 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.

  2. Prenatal stressors in rodents: Effects on behavior

    Directory of Open Access Journals (Sweden)

    Marta Weinstock

    2017-02-01

    Full Text Available The current review focuses on studies in rodents published since 2008 and explores possible reasons for any differences they report in the effects of gestational stress on various types of behavior in the offspring. An abundance of experimental data shows that different maternal stressors in rodents can replicate some of the abnormalities in offspring behavior observed in humans. These include, anxiety, in juvenile and adult rats and mice, assessed in the elevated plus maze and open field tests and depression, detected in the forced swim and sucrose-preference tests. Deficits were reported in social interaction that is suggestive of pathology associated with schizophrenia, and in spatial learning and memory in adult rats in the Morris water maze test, but in most studies only males were tested. There were too few studies on the novel object recognition test at different inter-trial intervals to enable a conclusion about the effect of prenatal stress and whether any deficits are more prevalent in males. Among hippocampal glutamate receptors, NR2B was the only subtype consistently reduced in association with learning deficits. However, like in humans with schizophrenia and depression, prenatal stress lowered hippocampal levels of BDNF, which were closely correlated with decreases in hippocampal long-term potentiation. In mice, down-regulation of BDNF appeared to occur through the action of gene-methylating enzymes that are already increased above controls in prenatally-stressed neonates. In conclusion, the data obtained so far from experiments in rodents lend support to a physiological basis for the neurodevelopmental hypothesis of schizophrenia and depression.

  3. Euthanasia using gaseous agents in laboratory rodents.

    Science.gov (United States)

    Valentim, A M; Guedes, S R; Pereira, A M; Antunes, L M

    2016-08-01

    Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously. Nevertheless, its aversive potential has been criticized in terms of animal welfare. The data available regarding the use of carbon dioxide (CO2), inhaled anaesthetics (such as isoflurane, sevoflurane, halothane and enflurane), as well as carbon monoxide and inert gases are discussed throughout this review. Euthanasia of fetuses and neonates is also addressed. A table listing currently available information to ease access to data regarding euthanasia techniques using gaseous agents in laboratory rodents was compiled. Regarding better animal welfare, there is currently insufficient evidence to advocate banning or replacing CO2 in the euthanasia of rodents; however, there are hints that alternative gases are more humane. The exposure to a volatile anaesthetic gas before loss of consciousness has been proposed by some scientific studies to minimize distress; however, the impact of such a measure is not clear. Areas of inconsistency within the euthanasia literature have been highlighted recently and stem from insufficient knowledge, especially regarding the advantages of the administration of isoflurane or sevoflurane over CO2, or other methods, before loss of consciousness. Alternative methods to minimize distress may include the development of techniques aimed at inducing death in the home cage of animals. Scientific outcomes have to be considered before choosing the most suitable euthanasia method to obtain the best results and accomplish the 3Rs (replacement, reduction and refinement). © The Author(s) 2015.

  4. Comparative anatomy of the prosubiculum, subiculum, presubiculum, postsubiculum, and parasubiculum in human, monkey, and rodent.

    Science.gov (United States)

    Ding, Song-Lin

    2013-12-15

    The subicular complex, including the prosubiculum (ProS), subiculum (Sub), presubiculum, postsubiculum (PoS), and parasubiculum (PaS), plays important roles in the medial temporal memory system and is heavily involved in many neurological diseases such as Alzheimer's disease and epilepsy. In the literature, the ProS (in primate) and PoS (in rodent) are inconstantly identified, making data comparison difficult across species. This review is an attempt to discuss equivalencies and extent of the five subicular components in human, monkey, and rodent based on available information on their cytoarchitecture, chemoarchitecture, molecular signature, and neural connectivity. All five subicular cortices exist in human, monkey, and rodent. In human and monkey, the ProS and Sub extend into the uncal region anteriorly, and the PoS and PaS reach the cingulate isthmus posteriorly. In rodent, most of the typical subicular cortices are located in the dorsal and caudal portions of the hippocampal formation, and the modified version of the ventral ProS and Sub corresponds to the modified description of the uncal ProS and Sub in monkey and human. An interesting triangular region in rodent located at the juncture of the PoS, PaS, retrosplenial cortex, and visual cortex appears to be the equivalent of the monkey area prostriata. Major connections of the five subicular cortices are also summarized based on unified criteria discussed in this review, with distinct connections revealed between the ProS and the Sub. Copyright © 2013 Wiley Periodicals, Inc.

  5. Simple, inexpensive computerized rodent activity meters.

    Science.gov (United States)

    Horton, R M; Karachunski, P I; Kellermann, S A; Conti-Fine, B M

    1995-10-01

    We describe two approaches for using obsolescent computers, either an IBM PC XT or an Apple Macintosh Plus, to accurately quantify spontaneous rodent activity, as revealed by continuous monitoring of the spontaneous usage of running activity wheels. Because such computers can commonly be obtained at little or no expense, and other commonly available materials and inexpensive parts can be used, these meters can be built quite economically. Construction of these meters requires no specialized electronics expertise, and their software requirements are simple. The computer interfaces are potentially of general interest, as they could also be used for monitoring a variety of events in a research setting.

  6. Harvesting behaviour of three central European rodents: Identifying the rodent pest in cereals

    Czech Academy of Sciences Publication Activity Database

    Heroldová, Marta; Tkadlec, Emil

    2011-01-01

    Roč. 30, č. 1 (2011), s. 82-84 ISSN 0261-2194 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : Apodemus sylvaticus * Apodemus uralensis * feeding behaviour * lab experiments * Microtus arvalis * rodent pest control Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.402, year: 2011

  7. A Survey of Zoonotic Pathogens Carried by Non-Indigenous Rodents at the Interface of the Wet Tropics of North Queensland, Australia.

    Science.gov (United States)

    Chakma, S; Picard, J; Duffy, R; Constantinoiu, C; Gummow, B

    2017-02-01

    In 1964, Brucella was isolated from rodents trapped in Wooroonooran National Park (WNP), in Northern Queensland, Australia. Genotyping of bacterial isolates in 2008 determined that they were a novel Brucella species. This study attempted to reisolate this species of Brucella from rodents living in the boundary area adjacent to WNP and to establish which endo- and ecto-parasites and bacterial agents were being carried by non-indigenous rodents at this interface. Seventy non-indigenous rodents were trapped [Mus musculus (52), Rattus rattus (17) and Rattus norvegicus (1)], euthanized and sampled on four properties adjacent to the WNP in July 2012. Organ pools were screened by culture for Salmonella, Leptospira and Brucella species, real-time PCR for Coxiella burnetii and conventional PCR for Leptospira. Collected ecto- and endo-parasites were identified using morphological criteria. The percentage of rodents carrying pathogens were Leptospira (40%), Salmonella choleraesuis ssp. arizonae (14.29%), ectoparasites (21.42%) and endoparasites (87%). Brucella and C. burnetii were not identified, and it was concluded that their prevalences were below 12%. Two rodent-specific helminthic species, namely Syphacia obvelata (2.86%) and Nippostrongylus brasiliensis (85.71%), were identified. The most prevalent ectoparasites belonged to Laelaps spp. (41.17%) followed by Polyplax spp. (23.53%), Hoplopleura spp. (17.65%), Ixodes holocyclus (17.64%) and Stephanocircus harrisoni (5.88%), respectively. These ectoparasites, except S. harrisoni, are known to transmit zoonotic pathogens such as Rickettsia spp. from rat to rat and could be transmitted to humans by other arthropods that bite humans. The high prevalence of pathogenic Leptospira species is of significant public health concern. This is the first known study of zoonotic agents carried by non-indigenous rodents living in the Australian wet-tropical forest interface. © 2015 Blackwell Verlag GmbH.

  8. Mycobacterial lesions in fish, amphibians, reptiles, rodents, lagomorphs, and ferrets with reference to animal models.

    Science.gov (United States)

    Reavill, Drury R; Schmidt, Robert E

    2012-01-01

    Mycobacteriosis is a serious disease across many animal species. Approximately more than 120 species are currently recognized in the genus Mycobacterium. This article describes the zoonotic potential of mycobacteria and mycobacteriosis in fish, amphibians, rodents, rabbits, and ferrets. It considers clinical signs; histology; molecular methods of identification, such as polymerase chain reaction and DNA sequencing; routes of infection; and disease progression. Studying the disease in animals may aid in understanding the pathogenesis of mycobacterial infections in humans and identify better therapy and preventative options such as vaccines.

  9. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents

    OpenAIRE

    Schiöth Helgi B; Foord Steven M; Fredriksson Robert; Haitina Tatjana; Gloriam David E

    2009-01-01

    Abstract Background The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs) is one of the largest gene families in most mammals and the most expl...

  10. Lead Levels in the Bones of Small Rodents from Alpine and Subalpine Habitats in the Tian-Shan Mountains, Kyrgyzstan

    Directory of Open Access Journals (Sweden)

    Zuzana Ballová

    2018-01-01

    Full Text Available High mountain areas are an appropriate indicator of anthropogenic lead (Pb, which can reach remote mountain ranges through long distance atmospheric transport. We compared the content of Pb in ecologically equivalent rodent species from Tian-Shan with European mountain ranges including the Tatra, Vitosha and Rila mountains. We used bone tissues from terminal tail vertebrae of small rodents for detection of Pb levels through electro-thermal atomic absorption spectroscopy (AAS. The tailbones of Tian-Shan rodents had significantly lower Pb levels than snow voles from the Tatra Mountains, but there was no significant difference in comparison with the Vitosha and Rila mountains. We can conclude that Tian-Shan shows lower pollution by Pb than the Tatras, which may be a result of prolonged industrialization of north-western Europe and strongly prevailing west winds in this region.

  11. Calorie restriction in rodents: Caveats to consider.

    Science.gov (United States)

    Ingram, Donald K; de Cabo, Rafael

    2017-10-01

    The calorie restriction paradigm has provided one of the most widely used and most useful tools for investigating mechanisms of aging and longevity. By far, rodent models have been employed most often in these endeavors. Over decades of investigation, claims have been made that the paradigm produces the most robust demonstration that aging is malleable. In the current review of the rodent literature, we present arguments that question the robustness of the paradigm to increase lifespan and healthspan. Specifically, there are several questions to consider as follows: (1) At what age does CR no longer produce benefits? (2) Does CR attenuate cognitive decline? (3) Are there negative effects of CR, including effects on bone health, wound healing, and response to infection? (4) How important is schedule of feeding? (5) How long does CR need to be imposed to be effective? (6) How do genotype and gender influence CR? (7) What role does dietary composition play? Consideration of these questions produce many caveats that should guide future investigations to move the field forward. Published by Elsevier B.V.

  12. Hunting, Food Preparation, and Consumption of Rodents in Lao PDR.

    Directory of Open Access Journals (Sweden)

    Kanokwan Suwannarong

    Full Text Available A cross-sectional study was conducted in 29 villages of Khamkeuth District in Bolikhamxay Province in the Lao PDR during March to May 2013. The study aimed to determine the characteristics associated with rodent consumption and related behaviors among different ethnic groups, ages, and genders. Five-hundred-eighty-four (584 males and females from 18-50 years of age participated in this study. Half of them were Hmong (292, 50% while 152 respondents were Lao-Tai (26% or other ethnic groups (140, 24%. Most of the respondents (79.5% had farming as their main occupation. Prevalences of the studied outcomes were high: 39.9 for hunting or capturing rodents in the previous year, 77.7% for preparing rodents as food, and 86.3% for rodent consumption. Multivariable logistic regression analysis showed that likelihood of these types of rodent contact was more consistently associated with behavioral factors (gathering things from the forest and elsewhere, cultivation-related activities, and taking measures to prevent rodent-borne disease than with socio-demographic, environmental, or cultural factors. The strongest associations were observed for gathering things; these associations were consistently positive and statistically significant. Although this study did not directly assess rodent-borne zoonosis risk, we believe that study findings raise concern that such risk may be substantial in the study area and other similar areas. Further epidemiological studies on the association between rodent-borne disease infection and rodent hunting, preparation for food, and consumption are recommended. Moreover, further studies are needed on the association between these potential exposure factors (i.e., rodent hunting, preparation for food, and consumption and rodent-borne infections, especially among ethnic groups like the Hmong in Lao PDR and those in neighboring countries with similar socio-demographic, environmental, behavioral and cultural contexts.

  13. SUSPECTED HYPERVITAMINOSIS D IN RED-RUMPED AGOUTI ( DASYPROCTA LEPORINA) RECEIVING A COMMERCIAL RODENT DIET.

    Science.gov (United States)

    Anderson, Kadie M; Lewandowski, Albert; Dennis, Patricia M

    2018-03-01

    An 8 yr, intact male red-rumped agouti ( Dasyprocta leporina) was evaluated for weight loss. Examination revealed poor body condition, hypercalcemia, elevated serum 25-hydroxyvitamin D, metastatic calcification of soft tissues, and hyperechoic kidneys. The diet, formulated for laboratory rodents, contained elevated levels of vitamin D 3 . Histopathology from a female conspecific that died 5 mo prior identified dystrophic mineralization and nephrosclerosis, suggestive of a vitamin D 3 toxicity. The male agouti responded well to a dietary reduction in vitamin D 3 and calcium. Six months into therapy, progressive renal failure was identified and was further managed with enalapril, phosphorus binders, and dietary manipulation. Suspected vitamin D 3 toxicity has been reported in pacas ( Cuniculus paca) and agouti and has been linked to exposure to New World primate diets. In this brief communication, an agouti developed suspected hypervitaminosis D after receiving a commercial rodent diet commonly fed to this species in captivity.

  14. Ventilation of multi-entranced rodent burrows by boundary layer eddies.

    Science.gov (United States)

    Brickner-Braun, Inbal; Zucker-Milwerger, Daniel; Braun, Avi; Turner, J Scott; Pinshow, Berry; Berliner, Pedro

    2014-12-01

    Rodent burrows are often assumed to be environments wherein the air has a high concentration of CO₂. Although high burrow [CO₂] has been recorded, many studies report burrow [CO₂] that differs only slightly from atmospheric concentrations. Here, we advocate that one of the reasons for these differences is the penetration into burrows of air gusts (eddies), which originate in the turbulent boundary layer and prevent build-up of CO₂. We have characterized the means by which burrows of Sundevall's jird, which are representative of the burrows of many rodent species with more than one entrance, are ventilated. Our results demonstrate that, even at low wind speeds, the random penetration of eddies into a burrow through its openings is sufficient to keep the burrow [CO₂] low enough to be physiologically inconsequential, even in its deep and remote parts. © 2014. Published by The Company of Biologists Ltd.

  15. Assessing the Diversity of Rodent-Borne Viruses: Exploring of High-Throughput Sequencing and Classical Amplification/Sequencing Approaches.

    Science.gov (United States)

    Drewes, Stephan; Straková, Petra; Drexler, Jan F; Jacob, Jens; Ulrich, Rainer G

    2017-01-01

    Rodents are distributed throughout the world and interact with humans in many ways. They provide vital ecosystem services, some species are useful models in biomedical research and some are held as pet animals. However, many rodent species can have adverse effects such as damage to crops and stored produce, and they are of health concern because of the transmission of pathogens to humans and livestock. The first rodent viruses were discovered by isolation approaches and resulted in break-through knowledge in immunology, molecular and cell biology, and cancer research. In addition to rodent-specific viruses, rodent-borne viruses are causing a large number of zoonotic diseases. Most prominent examples are reemerging outbreaks of human hemorrhagic fever disease cases caused by arena- and hantaviruses. In addition, rodents are reservoirs for vector-borne pathogens, such as tick-borne encephalitis virus and Borrelia spp., and may carry human pathogenic agents, but likely are not involved in their transmission to human. In our days, next-generation sequencing or high-throughput sequencing (HTS) is revolutionizing the speed of the discovery of novel viruses, but other molecular approaches, such as generic RT-PCR/PCR and rolling circle amplification techniques, contribute significantly to the rapidly ongoing process. However, the current knowledge still represents only the tip of the iceberg, when comparing the known human viruses to those known for rodents, the mammalian taxon with the largest species number. The diagnostic potential of HTS-based metagenomic approaches is illustrated by their use in the discovery and complete genome determination of novel borna- and adenoviruses as causative disease agents in squirrels. In conclusion, HTS, in combination with conventional RT-PCR/PCR-based approaches, resulted in a drastically increased knowledge of the diversity of rodent viruses. Future improvements of the used workflows, including bioinformatics analysis, will further

  16. Trophic Niche Differentiation in Rodents and Marsupials Revealed by Stable Isotopes.

    Directory of Open Access Journals (Sweden)

    Mauro Galetti

    Full Text Available Tropical rainforests support the greatest diversity of small mammals in the world, yet we have little understanding about the mechanisms that promote the coexistence of species. Diet partitioning can favor coexistence by lessening competition, and interspecific differences in body size and habitat use are usually proposed to be associated with trophic divergence. However, the use of classic dietary methods (e.g. stomach contents is challenging in small mammals, particularly in community-level studies, thus we used stable isotopes (δ13C and δ15N to infer about trophic niche. We investigated i how trophic niche is partitioned among rodent and marsupial species in three Atlantic forest sites and ii if interspecific body size and locomotor habit inequalities can constitute mechanisms underlying the isotopic niche partitioning. We found that rodents occupied a broad isotopic niche space with species distributed in different trophic levels and relying on diverse basal carbon sources (C3 and C4 plants. Surprisingly, on the other hand, marsupials showed a narrow isotopic niche, both in δ13C and δ15N dimensions, which is partially overlapped with rodents, contradicting their description as omnivores and generalists proposed classic dietary studies. Although body mass differences did not explained the divergence in isotopic values among species, groups of species with different locomotor habit presented clear differences in the position of the isotopic niche space, indicating that the use of different forest strata can favor trophic niche partitioning in small mammals communities. We suggest that anthropogenic impacts, such as habitat modification (logging, harvesting, can simplify the vertical structure of ecosystems and collapse the diversity of basal resources, which might affect negatively small mammals communities in Atlantic forests.

  17. Prevalence of infection with hantavirus in rodent populations of central Argentina

    Directory of Open Access Journals (Sweden)

    Olga V Suárez

    2003-09-01

    Full Text Available We studied hantavirus seroprevalence and virus variability in rodent populations in Diego Gaynor, northwest of Buenos Aires province, Argentina. Rodent samplings were conducted in railroads and cropfield borders in March and July 1999, September and December 2000, and March 2001. Antibody detection was performed by an enzyme link immunosorbent assay (ELISA, using the recombinant nucleoprotein of Andes (AND virus as antigen. Tissue samples were taken from positive antibody individuals in order to confirm the presence of hantavirus genomic material and to identify virus genotypes. Akodon azarae was the most abundant species, followed by Oligoryzomys flavescens, while Calomys laucha and C. musculinus were rarely caught. We found a rate of seroprevalence of 9.3% for a total sample of 291 A. azarae and 13.5% for 37 O. flavescens. After molecular analyses of hantavirus, we confirmed the presence of hantavirus genomic material in 16 individuals with ELISA (+ results and two individuals with ELISA (-. Four amplimers for each species were sequenced and compared to the corresponding sequences of representative hantaviruses. We identified the AND Cent Lec from three O. flavescens, and the Pergamino virus from four A. azarae and from one O. flavescens. A. azarae males had higher seroprevalence than females, and heavier individuals showed higher seroprevalence than lighter ones. We did not find seroprevalence differences according to sex in O. flavescens, although this result may have been produced by the low sample size. The lowest seroprevalence was found in a period of high rodent density, when juveniles prevailed in the population. We found higher seroprevalences than those detected in previous studies for other localities of central Argentina where cases of hantavirus pulmonary syndrome (HPS have been reported. The presence of AND Cent Lec virus in rodent populations of the study area, which is responsible of HPS cases in central Argentina, suggests

  18. Visual Landmarks Facilitate Rodent Spatial Navigation in Virtual Reality Environments

    Science.gov (United States)

    Youngstrom, Isaac A.; Strowbridge, Ben W.

    2012-01-01

    Because many different sensory modalities contribute to spatial learning in rodents, it has been difficult to determine whether spatial navigation can be guided solely by visual cues. Rodents moving within physical environments with visual cues engage a variety of nonvisual sensory systems that cannot be easily inhibited without lesioning brain…

  19. Early Eocene rodents (Mammalia) from the Subathu Formation of ...

    Indian Academy of Sciences (India)

    1997a, b). Most of the rodents from this stratigraphic level have been referred to a rather diverse family Cha- pattimyidae ... Herein we describe a new early Eocene rodent assemblage .... thick zone of brownish red shales that occur as a ..... 1997b;. Plate 3, figure 31). ...... northwestern Pakistan and remarks on the collision.

  20. Towards sustainable management of rodents in organic animal husbandry

    NARCIS (Netherlands)

    Meerburg, B.G.; Bonde, M.; Brom, F.W.A.; Endepols, S.; Jensen, A.N.; Leirs, H.; Lodal, J.; Singleton, G.R.; Pelz, H.J.; Rodenburg, T.B.; Kijlstra, A.

    2004-01-01

    From 26 to 28 May 2004 an international seminar was held in Wageningen, the Netherlands, about current knowledge and advice on rodent management on organic pig and poultry farms in Western Europe. This paper summarizes the discussions. Rodent management is necessary to protect the food production

  1. Morphological and functional maturation of Leydig cells: from rodent models to primates.

    Science.gov (United States)

    Teerds, Katja J; Huhtaniemi, Ilpo T

    2015-01-01

    Leydig cells (LC) are the sites of testicular androgen production. Development of LC occurs in the testes of most mammalian species as two distinct growth phases, i.e. as fetal and pubertal/adult populations. In primates there are indications of a third neonatal growth phase. LC androgen production begins in embryonic life and is crucial for the intrauterine masculinization of the male fetal genital tract and brain, and continues until birth after which it rapidly declines. A short post-natal phase of LC activity in primates (including human) termed 'mini-puberty' precedes the period of juvenile quiescence. The adult population of LC evolves, depending on species, in mid- to late-prepuberty upon reawakening of the hypothalamic-pituitary-testicular axis, and these cells are responsible for testicular androgen production in adult life, which continues with a slight gradual decline until senescence. This review is an updated comparative analysis of the functional and morphological maturation of LC in model species with special reference to rodents and primates. Pubmed, Scopus, Web of Science and Google Scholar databases were searched between December 2012 and October 2014. Studies published in languages other than English or German were excluded, as were data in abstract form only. Studies available on primates were primarily examined and compared with available data from specific animal models with emphasis on rodents. Expression of different marker genes in rodents provides evidence that at least two distinct progenitor lineages give rise to the fetal LC (FLC) population, one arising from the coelomic epithelium and the other from specialized vascular-associated cells along the gonad-mesonephros border. There is general agreement that the formation and functioning of the FLC population in rodents is gonadotrophin-responsive but not gonadotrophin-dependent. In contrast, although there is in primates some controversy on the role of gonadotrophins in the formation of

  2. Food habits of introduced rodents in high-elevation shrubland of Haleakala National Park, Maui, Hawai'i

    Science.gov (United States)

    Cole, F. Russell; Loope, Lloyd L.; Medeiros, Arthur C.; Howe, Cameron E.; Anderson, Laurel J.

    2000-01-01

    Mus musculus and Rattus rattus are ubiquitous consumers in the high-elevation shrubland of Haleakala National Park. Food habits of these two rodent species were determined from stomach samples obtained by snaptrapping along transects located at four different elevations during November 1984 and February, May, and August 1985. Mus musculus fed primarily on fruits, grass seeds, and arthropods. Rattus rattus ate various fruits, dicot leaves, and arthropods. Arthropods, many of which are endemic, were taken frequently by Mus musculus throughout the year at the highest elevation where plant food resources were scarce. Araneida, Lepidoptera (primarily larvae), Coleoptera, and Homoptera were the main arthropod taxa taken. These rodents, particularly Mus musculus, exert strong predation pressure on populations of arthropod species, including locally endemic species on upper Haleakala Volcano.

  3. Embryonic and fetal morphology in the lowland paca (Cuniculus paca): A precocial hystricomorph rodent.

    Science.gov (United States)

    El Bizri, Hani Rocha; Monteiro, Frederico Ozanan Barros; de Andrade, Rafael Dos Santos; Valsecchi, João; Guimarães, Diva Anelie de Araújo; Mayor, Pedro

    2017-12-01

    In mammals, the embryonic and fetal development of a species has evolved to maximize neonatal survival. In this study, we use a sample of 132 embryos/fetuses of wild lowland paca (Cuniculus paca), obtained over a period of 15 years through collaborative methods with local hunters in the Amazon to describe the intrauterine development of external and internal morphology of this Neotropical rodent. We also compare the newborn survival strategy in this species with other rodents. The crown-rump length (CRL) ranged between 0.6 and 24.6 cm. External features appeared in the following chronological order: limbs, eyelid buds, fusioned eyelids, genitalia, outer ear, tactile pelage, claws, skin, skin spots, covering pelage, teeth and open eyelids. Fetuses with CRL >19.5 cm presented all external features fully developed. The growth formula of fetal age was calculated as ∛W = 0.082 (t - 37.25), and age was accurately associated with CRL. We described the relationship between CRL and external and internal biometry. The liver declined in proportion within the internal cavity, while the relative volume of tubular gastrointestinal organs increased significantly along the embryo/fetal development. All organs, except the heart and the thymus, had similar relative volumes in advanced fetuses and adults. Our comparison of the intrauterine development in several rodent species indicates that the paca's reproductive strategy is comparable to species that are subject to low natural predation. Given that C. paca is perhaps the most hunted animal in Latin America, sustainable hunting throughout its range must take into account its relative reproductive performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Testing the limits of Rodent Sperm Analysis: azoospermia in an otherwise healthy wild rodent population.

    Science.gov (United States)

    Tannenbaum, Lawrence V; Thran, Brandolyn H; Willams, Keith J

    2009-01-01

    By comparing the sperm parameters of small rodents trapped at contaminated terrestrial sites and nearby habitat-matched noncontaminated locations, the patent-pending Rodent Sperm Analysis (RSA) method provides a direct health status appraisal for the maximally chemical-exposed mammalian ecological receptor in the wild. RSA outcomes have consistently allowed for as definitive determinations of receptor health as are possible at the present time, thereby streamlining the ecological risk assessment (ERA) process. Here, we describe the unanticipated discovery, at a contaminated US EPA Superfund National Priorities List site, of a population of Hispid cotton rats (Sigmodon hispidus), with a high percentage of adult males lacking sperm entirely (azoospermia). In light of the RSA method's role in streamlining ERAs and in bringing contaminated Superfund-type site investigations to closure, we consider the consequences of the discovery. The two matters specifically discussed are (1) the computation of a population's average sperm count where azoospermia is present and (2) the merits of the RSA method and its sperm parameter thresholds-for-effect when azoospermia is masked in an otherwise apparently healthy rodent population.

  5. Molecular diversification of Trichuris spp. from Sigmodontinae (Cricetidae) rodents from Argentina based on mitochondrial DNA sequences.

    Science.gov (United States)

    Callejón, Rocío; Robles, María Del Rosario; Panei, Carlos Javier; Cutillas, Cristina

    2016-08-01

    A molecular phylogenetic hypothesis is presented for the genus Trichuris based on sequence data from mitochondrial cytochrome c oxidase 1 (cox1) and cytochrome b (cob). The taxa consisted of nine populations of whipworm from five species of Sigmodontinae rodents from Argentina. Bayesian Inference, Maximum Parsimony, and Maximum Likelihood methods were used to infer phylogenies for each gene separately but also for the combined mitochondrial data and the combined mitochondrial and nuclear dataset. Phylogenetic results based on cox1 and cob mitochondrial DNA (mtDNA) revealed three clades strongly resolved corresponding to three different species (Trichuris navonae, Trichuris bainae, and Trichuris pardinasi) showing phylogeographic variation, but relationships among Trichuris species were poorly resolved. Phylogenetic reconstruction based on concatenated sequences had greater phylogenetic resolution for delimiting species and populations intra-specific of Trichuris than those based on partitioned genes. Thus, populations of T. bainae and T. pardinasi could be affected by geographical factors and co-divergence parasite-host.

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

    Directory of Open Access Journals (Sweden)

    EVELYN VALENCIA-PACHECO

    2011-09-01

    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.

  7. Systematic, cross-cortex variation in neuron numbers in rodents and primates.

    Science.gov (United States)

    Charvet, Christine J; Cahalane, Diarmuid J; Finlay, Barbara L

    2015-01-01

    Uniformity, local variability, and systematic variation in neuron numbers per unit of cortical surface area across species and cortical areas have been claimed to characterize the isocortex. Resolving these claims has been difficult, because species, techniques, and cortical areas vary across studies. We present a stereological assessment of neuron numbers in layers II-IV and V-VI per unit of cortical surface area across the isocortex in rodents (hamster, Mesocricetus auratus; agouti, Dasyprocta azarae; paca, Cuniculus paca) and primates (owl monkey, Aotus trivigratus; tamarin, Saguinus midas; capuchin, Cebus apella); these chosen to vary systematically in cortical size. The contributions of species, cortical areas, and techniques (stereology, "isotropic fractionator") to neuron estimates were assessed. Neurons per unit of cortical surface area increase across the rostro-caudal (RC) axis in primates (varying by a factor of 1.64-2.13 across the rostral and caudal poles) but less in rodents (varying by a factor of 1.15-1.54). Layer II-IV neurons account for most of this variation. When integrated into the context of species variation, and this RC gradient in neuron numbers, conflicts between studies can be accounted for. The RC variation in isocortical neurons in adulthood mirrors the gradients in neurogenesis duration in development. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  8. Reproducibility and replicability of rodent phenotyping in preclinical studies.

    Science.gov (United States)

    Kafkafi, Neri; Agassi, Joseph; Chesler, Elissa J; Crabbe, John C; Crusio, Wim E; Eilam, David; Gerlai, Robert; Golani, Ilan; Gomez-Marin, Alex; Heller, Ruth; Iraqi, Fuad; Jaljuli, Iman; Karp, Natasha A; Morgan, Hugh; Nicholson, George; Pfaff, Donald W; Richter, S Helene; Stark, Philip B; Stiedl, Oliver; Stodden, Victoria; Tarantino, Lisa M; Tucci, Valter; Valdar, William; Williams, Robert W; Würbel, Hanno; Benjamini, Yoav

    2018-04-01

    The scientific community is increasingly concerned with the proportion of published "discoveries" that are not replicated in subsequent studies. The field of rodent behavioral phenotyping was one of the first to raise this concern, and to relate it to other methodological issues: the complex interaction between genotype and environment; the definitions of behavioral constructs; and the use of laboratory mice and rats as model species for investigating human health and disease mechanisms. In January 2015, researchers from various disciplines gathered at Tel Aviv University to discuss these issues. The general consensus was that the issue is prevalent and of concern, and should be addressed at the statistical, methodological and policy levels, but is not so severe as to call into question the validity and the usefulness of model organisms as a whole. Well-organized community efforts, coupled with improved data and metadata sharing, have a key role in identifying specific problems and promoting effective solutions. Replicability is closely related to validity, may affect generalizability and translation of findings, and has important ethical implications. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Use of rodents as models of human diseases

    Directory of Open Access Journals (Sweden)

    Thierry F Vandamme

    2014-01-01

    Full Text Available Advances in molecular biology have significantly increased the understanding of the biology of different diseases. However, these discoveries have not yet been fully translated into improved treatments for patients with diseases such as cancers. One of the factors limiting the translation of knowledge from preclinical studies to the clinic has been the limitations of in vivo diseases models. In this brief review, we will discuss the advantages and disadvantages of rodent models that have been developed to simulate human pathologies, focusing in models that employ xenografts and genetic modification. Within the framework of genetically engineered mouse (GEM models, we will review some of the current genetic strategies for modeling diseases in the mouse and the preclinical studies that have already been undertaken. We will also discuss how recent improvements in imaging technologies may increase the information derived from using these GEMs during early assessments of potential therapeutic pathways. Furthermore, it is interesting to note that one of the values of using a mouse model is the very rapid turnover rate of the animal, going through the process of birth to death in a very short timeframe relative to that of larger mammalian species.

  10. BELAJAR BAHASA SECARA HOLISTIK: APAKAH PANDANGAN MURID ?

    Directory of Open Access Journals (Sweden)

    Zulkifli Osman

    2013-10-01

      Learning Language by Holistic Approach: What Atudent’s View”. A variety of teaching approaches such as structural approach, code-cognitive, communicative was implemented in the classroom. These approaches have their own specific strength and weakness. The cod-cognitive approach emphasizes on the ability of the students to mastering the language competence. The communicative approach likewise to enhance on the communication process only. The purpose of this study is to introduce the implementation of the holistic approach in teaching of the Malay Language to ensure pupils are able to learn the language as a whole or holistic. In order to obtain the student’s views on the implementation of this approach, questionnaire and semi-structured interview was implemented. Document analysis also used in order to support the data. One hundred and twenty five students are involved in this study whose consist of three classes of Form Four (SMA. Questionnaires and interviews were administered to the students after teaching modules run. Results showed that the language process by using the holistic approach is more attractive. This approach is able to increase the student’s motivation and language skills. Implications of the study are also discussed Keywords: Learning language, language learning, holistic approach,                   language teaching modules

  11. Competition between species of small mammals

    International Nuclear Information System (INIS)

    Grant, P.R.

    1978-01-01

    Interspecific competition has often been inferred from its results. In evolutionary time it has been responsible for patterns of regularity in the structure of mammalian communities, and in the morphological and ecological characteristics of the constituent species. In contemporary time it gives rise to reciprocal (complementary) numbers and distributions of two or more species. These inferences are strengthened by recent experimental demonstrations of competition between species of North American rodents. Recent observations and experiments are reviewed. The most thoroughly studied competitors are two species of microtine rodents, Microtus pennsylvanicus and Clethrionomys gapperi. Species which compete for space have been studied experimentally more often than have food competitors. Overt aggression is frequently implicated, but its importance in nature in relation to other means of interaction (e.g. through vocal or scent communication) is not known. The definitive study of competition for food between mammal species has yet to be performed

  12. Post-dispersal seed removal by ground-feeding rodents in tropical peatlands, Central Kalimantan, Indonesia

    Science.gov (United States)

    Blackham, Grace V.; Corlett, Richard T.

    2015-01-01

    Forested tropical peatlands in Southeast Asia are being rapidly converted to agriculture or degraded into non-forest vegetation. Although large areas have been abandoned, there is little evidence for subsequent forest recovery. As part of a study of forest degradation and recovery, we used seed removal experiments and rodent surveys to investigate the potential role of post-dispersal seed predation in limiting the regeneration of woody plants. Two 14-day seed removal trials were done in deforested and forested peatland habitat in Central Kalimantan, Indonesia. Seeds of Nephelium lappaceum, Syzygium muelleri, Artocarpus heterophyllus (all animal-dispersed) and Combretocarpus rotundatus (wind-dispersed) were tested. Significantly more seeds (82.8%) were removed in forest than non-forest (38.1%) and Combretocarpus had the lowest removal in both habitats. Most handled seeds were eaten in situ and little caching was observed. Six species of rodents were captured in forest and five in non-forest. The most trapped taxa were three Maxomys spp. in forest (85.5% of individuals) and Rattus tiomanicus in non-forest (74.8%). Camera traps confirmed that rodents were responsible for seed removal. Seed predation in deforested areas, which have a much lower seed rain than forest, may contribute to the low density and diversity of regenerating forest. PMID:26369444

  13. Oxidative Metabolism Genes Are Not Responsive to Oxidative Stress in Rodent Beta Cell Lines

    Directory of Open Access Journals (Sweden)

    Faer Morrison

    2012-01-01

    Full Text Available Altered expression of oxidative metabolism genes has been described in the skeletal muscle of individuals with type 2 diabetes. Pancreatic beta cells contain low levels of antioxidant enzymes and are particularly susceptible to oxidative stress. In this study, we explored the effect of hyperglycemia-induced oxidative stress on a panel of oxidative metabolism genes in a rodent beta cell line. We exposed INS-1 rodent beta cells to low (5.6 mmol/L, ambient (11 mmol/L, and high (28 mmol/L glucose conditions for 48 hours. Increases in oxidative stress were measured using the fluorescent probe dihydrorhodamine 123. We then measured the expression levels of a panel of 90 oxidative metabolism genes by real-time PCR. Elevated reactive oxygen species (ROS production was evident in INS-1 cells after 48 hours (P<0.05. TLDA analysis revealed a significant (P<0.05 upregulation of 16 of the 90 genes under hyperglycemic conditions, although these expression differences did not reflect differences in ROS. We conclude that although altered glycemia may influence the expression of some oxidative metabolism genes, this effect is probably not mediated by increased ROS production. The alterations to the expression of oxidative metabolism genes previously observed in human diabetic skeletal muscle do not appear to be mirrored in rodent pancreatic beta cells.

  14. Climatic niche conservatism and ecological opportunity in the explosive radiation of arvicoline rodents (Arvicolinae, Cricetidae).

    Science.gov (United States)

    Lv, Xue; Xia, Lin; Ge, Deyan; Wu, Yongjie; Yang, Qisen

    2016-05-01

    Climatic niche conservatism shapes patterns of diversity in many taxonomic groups, while ecological opportunity (EO) can trigger rapid speciation that is less constrained by the amount of time a lineage has occupied a given habitat. These two processes are well studied, but limited research has considered their joint and relative roles in shaping diversity patterns. We characterized climatic and biogeographic variables for 102 species of arvicoline rodents (Arvicolinae, Cricetidae), testing the effects of climatic niche conservatism and EO on arvicoline diversification as lineages transitioned between biogeographic regions. We found that the amount of time a lineage has occupied a precipitation niche is positively correlated with diversity along a precipitation gradient, suggesting climatic niche conservatism. In contrast, shift in diversification rate explained diversity patterns along a temperature gradient. Our results suggest that an indirect relationship exists between temperature and diversification that is associated with EO as arvicoline rodents colonized warm Palearctic environments. Climatic niche conservatism alone did not fully explain diversity patterns under density-dependence, highlighting the additional importance of EO-related processes in promoting the explosive radiation in arvicoline rodents and shaping diversity pattern among biogeographic regions and along climatic gradients. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  15. Molecular identification of Taenia mustelae cysts in subterranean rodent plateau zokors (Eospalax baileyi).

    Science.gov (United States)

    Zhao, Fang; Ma, Jun-Ying; Cai, Hui-Xia; Su, Jian-Ping; Hou, Zhi-Bin; Zhang, Tong-Zuo; Lin, Gong-Hua

    2014-07-01

    Cestode larvae spend one phase of their two-phase life cycle in the viscera of rodents, but cases of cestodes infecting subterranean rodents have only been rarely observed. To experimentally gain some insight into this phenomenon, we captured approximately 300 plateau zokors (Eospalax baileyi), a typical subterranean rodent inhabiting the Qinghai-Tibet Plateau, and examined their livers for the presence of cysts. Totally, we collected five cysts, and using a mitochondrial gene (cox1) and two nuclear genes (pepck and pold) as genetic markers, we were able to analyze the taxonomy of the cysts. Both the maximum likelihood and Bayesian methods showed that the cysts share a monophyly with Taenia mustelae, while Kimura 2-parameter distances and number of different sites between our sequences and T. mustelae were far less than those found between the examined sequences and other Taeniidae species. These results, alongside supporting paraffin section histology, imply that the cysts found in plateau zokors can be regarded as larvae of T. mustelae, illustrating that zokors are a newly discovered intermediate host record of this parasite.

  16. Large Animal Stroke Models vs. Rodent Stroke Models, Pros and Cons, and Combination?

    Science.gov (United States)

    Cai, Bin; Wang, Ning

    2016-01-01

    Stroke is a leading cause of serious long-term disability worldwide and the second leading cause of death in many countries. Long-time attempts to salvage dying neurons via various neuroprotective agents have failed in stroke translational research, owing in part to the huge gap between animal stroke models and stroke patients, which also suggests that rodent models have limited predictive value and that alternate large animal models are likely to become important in future translational research. The genetic background, physiological characteristics, behavioral characteristics, and brain structure of large animals, especially nonhuman primates, are analogous to humans, and resemble humans in stroke. Moreover, relatively new regional imaging techniques, measurements of regional cerebral blood flow, and sophisticated physiological monitoring can be more easily performed on the same animal at multiple time points. As a result, we can use large animal stroke models to decrease the gap and promote translation of basic science stroke research. At the same time, we should not neglect the disadvantages of the large animal stroke model such as the significant expense and ethical considerations, which can be overcome by rodent models. Rodents should be selected as stroke models for initial testing and primates or cats are desirable as a second species, which was recommended by the Stroke Therapy Academic Industry Roundtable (STAIR) group in 2009.

  17. A Community-Based Surveillance on Determinants of Rodent Infestation

    Directory of Open Access Journals (Sweden)

    Hsiu-Hua Pai

    2003-01-01

    Full Text Available Rodent infestation is an important factor in the transmission of infectious diseases of public health importance. From October to November 1998, surveillance stations were established in 110 boroughs of Kaohsiung City in southern Taiwan. Boroughs were chosen by random sampling 10 boroughs from each of 11 districts (464 boroughs in the city. The extent of rodent infestation was determined by cage trapping. The possibility of applying a community-based control program was evaluated by investigating associated demographic and environmental factors as well as related knowledge, attitudes, and behaviors. A total of 90 rodents were trapped in 41% of the 110 boroughs. Using univariate analyses, 17 factors were significantly associated with rodent infestation. A lack of knowledge that rodent control relies on community cooperation was the most important factor among the seven variables associated with the extent of rodent infestation (OR 3.1 by logistic multiple regression. This revealed the importance of community cooperation in controlling rodent infestation. Moreover, improvement of environmental hygiene associated with garbage problems, such as cleanliness of storage rooms and closets, and the hygiene of empty space and resource recycling stations should not be ignored.

  18. Landscape epidemiology in urban environments: The example of rodent-borne Trypanosoma in Niamey, Niger.

    Science.gov (United States)

    Rossi, Jean-Pierre; Kadaouré, Ibrahima; Godefroid, Martin; Dobigny, Gauthier

    2017-10-05

    Trypanosomes are protozoan parasites found worldwide, infecting humans and animals. In the past decade, the number of reports on atypical human cases due to Trypanosoma lewisi or T. lewisi-like has increased urging to investigate the multiple factors driving the disease dynamics, particularly in cities where rodents and humans co-exist at high densities. In the present survey, we used a species distribution model, Maxent, to assess the spatial pattern of Trypanosoma-positive rodents in the city of Niamey. The explanatory variables were landscape metrics describing urban landscape composition and physiognomy computed from 8 land-cover classes. We computed the metrics around each data location using a set of circular buffers of increasing radii (20m, 40m, 60m, 80m and 100m). For each spatial resolution, we determined the optimal combination of feature class and regularization multipliers by fitting Maxent with the full dataset. Since our dataset was small (114 occurrences) we expected an important uncertainty associated to data partitioning into calibration and evaluation datasets. We thus performed 350 independent model runs with a training dataset representing a random subset of 80% of the occurrences and the optimal Maxent parameters. Each model yielded a map of habitat suitability over Niamey, which was transformed into a binary map implementing a threshold maximizing the sensitivity and the specificity. The resulting binary maps were combined to display the proportion of models that indicated a good environmental suitability for Trypanosoma-positive rodents. Maxent performed better with landscape metrics derived from buffers of 80m. Habitat suitability for Trypanosoma-positive rodents exhibited large patches linked to urban features such as patch richness and the proportion of landscape covered by concrete or tarred areas. Such inferences could be helpful in assessing areas at risk, setting of monitoring programs, public and medical staff awareness or even

  19. Locomotor pattern fails to predict foramen magnum angle in rodents, strepsirrhine primates, and marsupials.

    Science.gov (United States)

    Ruth, Aidan A; Raghanti, Mary Ann; Meindl, Richard S; Lovejoy, C Owen

    2016-05-01

    Foramen magnum position has traditionally been used as an indicator of bipedality because it has been thought to favor a more "balanced" skull position. Here, we analyzed foramen magnum angle (FMA) in relation to locomotion in three mammalian orders that include bipedal or orthograde species in addition to quadrupedal or pronograde species. In marsupials and strepsirrhine primates, we found that there is no relationship between locomotor pattern and FMA. In rodents, we found that there is a significant difference in FMA between bipedal and quadrupedal rodents. However, when these species are analyzed in the context of enlarged auditory bullae, this relationship is no longer significant. Additionally, we find a significant relationship between relative brain size and FMA in strepsirrhine primates. Taken together, these data indicate that several developmental modules of the cranium influence FMA, but that locomotion does not. We caution that basicranial evolution is a complex phenomenon that must be explored in the context of each taxon's unique evolutionary and developmental history. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Sharing the space: distribution, habitat segregation and delimitation of a new sympatric area of subterranean rodents.

    Directory of Open Access Journals (Sweden)

    Bruno Busnello Kubiak

    Full Text Available Subterranean rodents of the genus Ctenomys usually present an allopatric or parapatric distribution. Currently, two cases of sympatry have been recognized for the genus in the coastal dunes of southern Argentina and southern Brazil. In this context, they are ideal models to test hypotheses about the factors that delimit the patterns of space use and to understand interspecific interactions in small mammals. We investigated the vegetation structure, plant biomass and soil hardness selected by two species of subterranean rodents (Ctenomys flamarioni and C. minutus when distributed in sympatry and allopatry from nine different areas along the line of coastal dunes in southern Brazil. In addition, our work presents a new record of a third area of sympatry for the genus Ctenomys. Ctenomys flamarioni and C. minutus show habitat segregation in the area where they occur in sympatry. These species show segregation in their selection of microhabitats, differing in relation to soil hardness, plant biomass, and plant cover. Ctenomys flamarioni showed a distinction in habitat selection when occurring in allopatry and sympatry, whereas C. minutus selected the same habitat characteristics under both conditions. A possible explanation to the observed pattern is that these species have acquired different adaptations over time which allows them the ability to exploit different resources and thus avoid competitive interactions all together.

  1. Network Analysis of Rodent Transcriptomes in Spaceflight

    Science.gov (United States)

    Ramachandran, Maya; Fogle, Homer; Costes, Sylvain

    2017-01-01

    Network analysis methods leverage prior knowledge of cellular systems and the statistical and conceptual relationships between analyte measurements to determine gene connectivity. Correlation and conditional metrics are used to infer a network topology and provide a systems-level context for cellular responses. Integration across multiple experimental conditions and omics domains can reveal the regulatory mechanisms that underlie gene expression. GeneLab has assembled rich multi-omic (transcriptomics, proteomics, epigenomics, and epitranscriptomics) datasets for multiple murine tissues from the Rodent Research 1 (RR-1) experiment. RR-1 assesses the impact of 37 days of spaceflight on gene expression across a variety of tissue types, such as adrenal glands, quadriceps, gastrocnemius, tibalius anterior, extensor digitorum longus, soleus, eye, and kidney. Network analysis is particularly useful for RR-1 -omics datasets because it reinforces subtle relationships that may be overlooked in isolated analyses and subdues confounding factors. Our objective is to use network analysis to determine potential target nodes for therapeutic intervention and identify similarities with existing disease models. Multiple network algorithms are used for a higher confidence consensus.

  2. Rodent models of adaptive decision making.

    Science.gov (United States)

    Izquierdo, Alicia; Belcher, Annabelle M

    2012-01-01

    Adaptive decision making affords the animal the ability to respond quickly to changes in a dynamic environment: one in which attentional demands, cost or effort to procure the reward, and reward contingencies change frequently. The more flexible the organism is in adapting choice behavior, the more command and success the organism has in navigating its environment. Maladaptive decision making is at the heart of much neuropsychiatric disease, including addiction. Thus, a better understanding of the mechanisms that underlie normal, adaptive decision making helps achieve a better understanding of certain diseases that incorporate maladaptive decision making as a core feature. This chapter presents three general domains of methods that the experimenter can manipulate in animal decision-making tasks: attention, effort, and reward contingency. Here, we present detailed methods of rodent tasks frequently employed within these domains: the Attentional Set-Shift Task, Effortful T-maze Task, and Visual Discrimination Reversal Learning. These tasks all recruit regions within the frontal cortex and the striatum, and performance is heavily modulated by the neurotransmitter dopamine, making these assays highly valid measures in the study of psychostimulant addiction.

  3. Navigating actions through the rodent parietal cortex

    Directory of Open Access Journals (Sweden)

    Jonathan R. Whitlock

    2014-05-01

    Full Text Available The posterior parietal cortex (PPC participates in a manifold of cognitive functions, including visual attention, working memory, spatial processing and movement planning. Given the vast interconnectivity of PPC with sensory and motor areas, it is not surprising that neuronal recordings show that PPC often encodes mixtures of spatial information as well as the movements required to reach a goal. Recent work sought to discern the relative strength of spatial versus motor signaling in PPC by recording single unit activity in PPC of freely behaving rats during selective changes in either the spatial layout of the local environment or in the pattern of locomotor behaviors executed during navigational tasks. The results revealed unequivocally a predominant sensitivity of PPC neurons to locomotor action structure, with subsets of cells even encoding upcoming movements more than 1 second in advance. In light of these and other recent findings in the field, I propose that one of the key contributions of PPC to navigation is the synthesis of goal-directed behavioral sequences, and that the rodent PPC may serve as an apt system to investigate cellular mechanisms for spatial motor planning as traditionally studied in humans and monkeys.

  4. First Isolates of Leptospira spp., from Rodents Captured in Angola

    Science.gov (United States)

    Fortes-Gabriel, Elsa; Carreira, Teresa; Vieira, Maria Luísa

    2016-01-01

    Rodents play an important role in the transmission of pathogenic Leptospira spp. However, in Angola, neither the natural reservoirs of these spirochetes nor leptospirosis diagnosis has been considered. Regarding this gap, we captured rodents in Luanda and Huambo provinces to identify circulating Leptospira spp. Rodent kidney tissue was cultured and DNA amplified and sequenced. Culture isolates were evaluated for pathogenic status and typing with rabbit antisera; polymerase chain reaction (PCR) and sequencing were also performed. A total of 37 rodents were captured: Rattus rattus (15, 40.5%), Rattus norvegicus (9, 24.3%), and Mus musculus (13, 35.2%). Leptospiral DNA was amplified in eight (21.6%) kidney samples. From the cultures, we obtained four (10.8%) Leptospira isolates belonging to the Icterohaemorrhagiae and Ballum serogroups of Leptospira interrogans and Leptospira borgpetersenii genospecies, respectively. This study provides information about circulating leptospires spread by rats and mice in Angola. PMID:26928840

  5. Prevalence of leptospirosis and toxoplasmosis: A study of rodents ...

    African Journals Online (AJOL)

    prevalence of toxoplasmosis in child-bearing women in rural Sudan is even higher ranging ... crops. Animal trapping. Live rodents and shrews were captured in cultivated ..... P., Hodný, Z. & Vondrová, M. (2011) Fatal attraction phenomenon in.

  6. First Isolates of Leptospira spp., from Rodents Captured in Angola.

    Science.gov (United States)

    Fortes-Gabriel, Elsa; Carreira, Teresa; Vieira, Maria Luísa

    2016-05-04

    Rodents play an important role in the transmission of pathogenic Leptospira spp. However, in Angola, neither the natural reservoirs of these spirochetes nor leptospirosis diagnosis has been considered. Regarding this gap, we captured rodents in Luanda and Huambo provinces to identify circulating Leptospira spp. Rodent kidney tissue was cultured and DNA amplified and sequenced. Culture isolates were evaluated for pathogenic status and typing with rabbit antisera; polymerase chain reaction (PCR) and sequencing were also performed. A total of 37 rodents were captured: Rattus rattus (15, 40.5%), Rattus norvegicus (9, 24.3%), and Mus musculus (13, 35.2%). Leptospiral DNA was amplified in eight (21.6%) kidney samples. From the cultures, we obtained four (10.8%) Leptospira isolates belonging to the Icterohaemorrhagiae and Ballum serogroups of Leptospira interrogans and Leptospira borgpetersenii genospecies, respectively. This study provides information about circulating leptospires spread by rats and mice in Angola. © The American Society of Tropical Medicine and Hygiene.

  7. Morphological study of liver of mice-like rodents from the areas of Altai region exposed to radiation pollution

    International Nuclear Information System (INIS)

    Lushnikova, E.L.; Molodykh, O.P.; Nepomnyashikh, L.M.

    1997-01-01

    Morphofunctional liver state of two mice-like rodents species caught at the three areas of Altai region exposed to radiation during nuclear tests at Semipalatinsk site was studied. It was shown that the stereotype morphofunctional changes in the liver of both rodent species were developed under chronical influence of low doses of radiation and chemical contamination. These changes are manifested as dystrophic disorders of hepatocytes and hemodynamic disturbances accompanied by a decrease of volume ratio of sinusoidal capillaries to hepatocytes and stroma to parenchyma. Hyperglicogenosis, redistribution of the main cytoplasmic organelles, and considerably reduction of the volume densities of mitochondria, smooth and rough endoplasmic reticulum are the leading ultrastructural changes. Moreover, character and manifestation of the changes are determined by ecological belonging and correlated with intensity of anthropogenic pollution. The role of these changes in development of long term pathology are discussed

  8. Geographic patterns of genetic variation and conservation consequences in three South American rodents.

    Science.gov (United States)

    Miranda, Gustavo B; Andrades-Miranda, Jaqueline; Oliveira, Luiz F B; Langguth, Alfredo; Mattevi, Margarete S

    2007-12-01

    In this study, the geographic patterns of genetic variation of three rodent species belonging to the tribe Oryzomyini were investigated using the mitochondrial cytochrome b and nuclear IRBP genes in biomes that are undergoing degradation processes to a greater or lesser degree. The samples are from 25 collecting localities distributed throughout the Amazon, Cerrado, Atlantic Forest, and Pampa biomes. The results show that the three species have a population and geographic structure, besides being in demographic equilibrium. The phylogenetic analyses performed on Euryoryzomys russatus and Hylaeamys megacephalus showed these specimens grouped in three distinct clades forming geographic gradients (North-South direction in H. megacephalus). Intraspecific genetic divergence was higher in H. megacephalus (4.53%), followed by E. russatus (1.79%), and lowest in Sooretamys angouya (0.88%). The results obtained indicate that, necessarily, the management strategies to preserve genetic diversity should be different for each species, since each of them presented specific population parameters.

  9. Description of Leishmania (Leishmania forattinii sp. n., a new parasite infecting opossums and rodents in Brazil

    Directory of Open Access Journals (Sweden)

    Elizaide L. A. Yoshida

    1993-09-01

    Full Text Available A new parasite species of Leishmania is described, L. (Leishmania forattinii sp. n., which was isolated from a pooled triturate of liver and spleen of a opossum (Didelphis marsupialis aurita and from skin samples from a rodent (Proechmys iheringi denigratus, captured in primary forest on the Atlantic Cost of Brazil. Our results on the basis of biological and molecular criteria indicate that this taxonomically distinct parasite ias a new species of the L. mexicana complex, but closely related to L. (L. aristidesi Laison & shaw, 1979, as revelated by phenetic and phylogenetic numerical analyses of the enzyme data. L. forattinii was clearly distinguishable from other Leishmania species of the genus usisng enzyme electrophoresis, monoclonal antibodies, molecular karyotypes, analysis of restriction enzyme digestion patterns of kinetoplast DNA (kDNA, as well as the use of kDNA hybridization procedures.

  10. Template based rodent brain extraction and atlas mapping.

    Science.gov (United States)

    Weimin Huang; Jiaqi Zhang; Zhiping Lin; Su Huang; Yuping Duan; Zhongkang Lu

    2016-08-01

    Accurate rodent brain extraction is the basic step for many translational studies using MR imaging. This paper presents a template based approach with multi-expert refinement to automatic rodent brain extraction. We first build the brain appearance model based on the learning exemplars. Together with the template matching, we encode the rodent brain position into the search space to reliably locate the rodent brain and estimate the rough segmentation. With the initial mask, a level-set segmentation and a mask-based template learning are implemented further to the brain region. The multi-expert fusion is used to generate a new mask. We finally combine the region growing based on the histogram distribution learning to delineate the final brain mask. A high-resolution rodent atlas is used to illustrate that the segmented low resolution anatomic image can be well mapped to the atlas. Tested on a public data set, all brains are located reliably and we achieve the mean Jaccard similarity score at 94.99% for brain segmentation, which is a statistically significant improvement compared to two other rodent brain extraction methods.

  11. Pyramidal cells in V1 of African rodents are bigger more branched and more spiny than those in primates.

    Directory of Open Access Journals (Sweden)

    Guy eElston

    2014-02-01

    Full Text Available Pyramidal cells are characterised by markedly different sized dendritic trees, branching patterns and spine density across the cortical mantle. Moreover, pyramidal cells have been shown to differ in structure among homologous cortical areas in different species; however, most of these studies have been conducted in primates. Whilst pyramidal cells have been quantified in a few cortical areas in some other species there are, as yet, no uniform comparative data on pyramidal cell structure in a homologous cortical area among species in different Orders. Here we studied layer III pyramidal cells in V1 of three species of rodents, the greater cane rat, highveld gerbil and four-striped mouse, by the same methodology used to sample data from layer III pyramidal cells in primates. The data reveal markedly different trends between rodents and primates: there is an appreciable increase in the size, branching complexity and number of spines in the dendritic trees of pyramidal cells with increasing size of V1 in the brain in rodents, whereas there is relatively little difference in primates. Moreover, pyramidal cells in rodents are larger, more branched and more spinous than those in primates. For example, the dendritic trees of pyramidal cells in V1 of the cane rat are nearly three times larger, and have more than ten times the number of spines in their basal dendritic trees, than those in V1 of the macaque (7900 and 600, respectively, which has a V1 40 times the size that of the cane rat. It remains to be determined to what extent these differences may result from developmental differences or reflect evolutionary and/or processing specializations.

  12. Detection of IgE in the sera of rodents: comparison of the applicability of ELISA and RIA

    Energy Technology Data Exchange (ETDEWEB)

    Reiner, G; Zahner, H [Institut fuer Parasitologie der Justus-Liebig-Universitaet Giessen, Germany, F.R.; Haque, A [Institut Pasteur, 59 - Lille (France). Centre d' Immunologie et de Biologie Parasitaire

    1984-04-13

    RIA and ELISA were compared for their ability to detect IgE in different rodent species. With a sheep anti-rat IgE antibody good correlation (P < 0.001) between the 2 assay methods for IgE was found in rats. RIA failed to detect the IgE of Mastomys natalensis while ELISA proved to be a suitable test. However, both tests failed to measure IgE in sera of Nile rats.

  13. Description of the helminth communities of sympatric rodents (Muroidea: Cricetidae) from the Atlantic Forest in northeastern Argentina.

    Science.gov (United States)

    Panisse, Guillermo; Robles, María Del Rosario; Digiani, María Celina; Notarnicola, Juliana; Galliari, Carlos; Navone, Graciela Teresa

    2017-10-17

    Taxonomic and ecological aspects of the helminths found in the assemblage of sigmodontine rodents (Cricetidae-Muroidea) of the Atlantic Forest in Argentina are studied in this paper. The following species Akodon montensis, Brucepattersonius sp. and Thaptomys nigrita (Tribe Akodontini), as well as, Euryoryzomys russatus, Nectomys squamipes, Oligoryzomys nigripes, and Sooretamys angouya (Tribe Oryzomyini) are analyzed. A complete taxonomic list with a total of 25 species of helminths, including Digenea (Dicrocoeliidae), Cestoda (Hymenolepididae) and Nematoda (Trichuridae, Capillariidae, Cooperidae, Helligmonellidae, Oxyuridae, and Onchocercidae) is provided. Twenty new host and locality records for Misiones, Argentina, are reported and the results of the ecological descriptors of component communities are given. The highest value of richness was observed for A. montensis (S=8) and E. russatus (S=7). The diversity index (H´) reached values between 1.03 and 1.39 in all rodents, with the exception of N. squamipes that reached 0.75. The equitability indeces with highest value were observed for T. nigrita and E. russatus. The Berger-Parker index of dominance was similar for all host species. The highest prevalence, mean abundance and mean intensity values corresponded to Nippostrongylinae, followed by Syphacinii. This survey constitutes the report with the most diverse parasitic assemblage of rodents described for the Atlantic Forest ecoregion and for Argentina.

  14. Multiplicity of nuclear receptor activation by PFOA and PFOS in primary human and rodent hepatocytes

    International Nuclear Information System (INIS)

    Bjork, J.A.; Butenhoff, J.L.; Wallace, K.B.

    2011-01-01

    Perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) are surface active fluorochemicals that, due to their exceptional stability to degradation, are persistent in the environment. Both PFOA and PFOS are eliminated slowly in humans, with geometric mean serum elimination half-lives estimated at 3.5 and 4.8 years, respectively. The biological activity of PFOA and PFOS in rodents is attributed primarily to transactivation of the nuclear receptor peroxisome proliferator activated receptor alpha (PPARA), which is an important regulator of lipid and carbohydrate metabolism. However, there are significant species-specific differences in the response to PFOA and PFOS exposure; non-rodent species, including humans, are refractory to several but not all of these effects. Many of the metabolic effects have been attributed to the activation of PPARA; however, recent studies using PPARα knockout mice demonstrate residual PPARA-independent effects, some of which may involve the activation of alternate nuclear receptors, including NR1I2 (PXR), NR1I3 (CAR), NR1H3 (LXRA), and NR1H4 (FXR). The objective of this investigation was to characterize the activation of multiple nuclear receptors and modulation of metabolic pathways associated with exposure to PFOA and PFOS, and to compare and contrast the effects between rat and human primary liver cells using quantitative reverse transcription PCR (RT-qPCR). Our results demonstrate that multiple nuclear receptors participate in the metabolic response to PFOA and PFOS exposure resulting in a substantial shift from carbohydrate metabolism to fatty acid oxidation and hepatic triglyceride accumulation in rat liver cells. This shift in intermediary metabolism was more pronounced for PFOA than PFOS. Furthermore, while there is some similarity in the activation of metabolic pathways between rat and humans, particularly in PPARA regulated responses; the changes in primary human cells were more subtle and possibly reflect an adaptive

  15. Wildfires alter rodent community structure across four vegetation types in southern California, USA

    Science.gov (United States)

    Brehme, Cheryl S.; Clark, Denise R.; Rochester, Carlton J.; Fisher, Robert N.

    2011-01-01

    We surveyed burned and unburned plots across four habitat reserves in San Diego County, California, USA, in 2005 and 2006, to assess the effects of the 2003 wildfires on the community structure and relative abundance of rodent species. The reserves each contained multiple vegetation types (coastal sage scrub, chaparral, woodland, and grassland) and spanned from 250 m to 1078 m in elevation. Multivariate analyses revealed a more simplified rodent community structure in all burned habitats in comparison to unburned habitats. Reduction in shrub and tree cover was highly predictive of changes in post-fire rodent community structure in the burned coastal sage scrub and chaparral habitats. Reduction in cover was not predictive for the less substantially burned woodlands and grasslands, for which we hypothesized that interspecific competition played a greater role in post-fire community structure. Across vegetation types, generalists and open habitat specialists typically increased in relative abundance, whereas closed habitat specialists decreased. We documented significant increases in relative abundance of the deer mouse (Peromyscus maniculatus Wagner) and Dulzura kangaroo rat (Dipodomys simulans Merriam). In contrast, we found significant decreases in relative abundance for the California mouse (Peromyscus californicus Gambel), San Diego pocket mouse (Chaetodipus fallax Merriam), desert woodrat (Neotoma lepida Thomas), and brush mouse (Peromyscus boylii Baird). Currently, our research program involves assessment of whether habitat conservation plans (HCPs) in southern California provide long-term protection to HCP covered species, as well as preserve ecosystem function. The scenario of increased wildfires needs to be incorporated into this assessment. We discuss our results in relation to management and conservation planning under a future scenario of larger and more frequent wildfires in southern California.

  16. Anatomical and nutritional adaptations in African rodents

    African Journals Online (AJOL)

    Cricetomys gambianus, Mystromys albicaudatus, Thallomys paedulcus and Saccostomus campestris). The stomachs of all species are markedly sac- culated with a highly modified corpus containing either numerous papillae or several diverticula ...

  17. The Impact of Centrally-acting Pesticidal/Environmental Toxicants on the Neuroendocrine Regulation of Reproductive Function in the Female Rodent: Revelant to Human Reproductive Risk Assessment.

    Science.gov (United States)

    In mammals, the secretion of gonadotropin-releasing hormone (GnRH) from the brain hypothalamic median eminence constitutes the final common path to the pituitary that results in the ovulatory surge of luteinizing hormone (LH). In rodent test species, a growing number of environme...

  18. Contrasting Patterns in Mammal–Bacteria Coevolution: Bartonella and Leptospira in Bats and Rodents

    Science.gov (United States)

    Lei, Bonnie R.; Olival, Kevin J.

    2014-01-01

    Background Emerging bacterial zoonoses in bats and rodents remain relatively understudied. We conduct the first comparative host–pathogen coevolutionary analyses of bacterial pathogens in these hosts, using Bartonella spp. and Leptospira spp. as a model. Methodology/Principal Findings We used published genetic data for 51 Bartonella genotypes from 24 bat species, 129 Bartonella from 38 rodents, and 26 Leptospira from 20 bats. We generated maximum likelihood and Bayesian phylogenies for hosts and bacteria, and tested for coevoutionary congruence using programs ParaFit, PACO, and Jane. Bartonella spp. and their bat hosts had a significant coevolutionary fit (ParaFitGlobal = 1.9703, P≤0.001; m2 global value = 7.3320, P≤0.0001). Bartonella spp. and rodent hosts also indicated strong overall patterns of cospeciation (ParaFitGlobal = 102.4409, P≤0.001; m2 global value = 86.532, P≤0.0001). In contrast, we were unable to reject independence of speciation events in Leptospira and bats (ParaFitGlobal = 0.0042, P = 0.84; m2 global value = 4.6310, P = 0.5629). Separate analyses of New World and Old World data subsets yielded results congruent with analysis from entire datasets. We also conducted event-based cophylogeny analyses to reconstruct likely evolutionary histories for each group of pathogens and hosts. Leptospira and bats had the greatest number of host switches per parasite (0.731), while Bartonella and rodents had the fewest (0.264). Conclusions/Significance In both bat and rodent hosts, Bartonella exhibits significant coevolution with minimal host switching, while Leptospira in bats lacks evolutionary congruence with its host and has high number of host switches. Reasons underlying these variable coevolutionary patterns in host range are likely due to differences in disease-specific transmission and host ecology. Understanding the coevolutionary patterns and frequency of host-switching events between bacterial pathogens and

  19. Arvicanthis ansorgei, a Novel Model for the Study of Sleep and Waking in Diurnal Rodents

    Science.gov (United States)

    Hubbard, Jeffrey; Ruppert, Elisabeth; Calvel, Laurent; Robin-Choteau, Ludivine; Gropp, Claire-Marie; Allemann, Caroline; Reibel, Sophie; Sage-Ciocca, Dominique; Bourgin, Patrice

    2015-01-01

    Study Objectives: Sleep neurobiology studies use nocturnal species, mainly rats and mice. However, because their daily sleep/wake organization is inverted as compared to humans, a diurnal model for sleep studies is needed. To fill this gap, we phenotyped sleep and waking in Arvicanthis ansorgei, a diurnal rodent widely used for the study of circadian rhythms. Design: Video-electroencephalogram (EEG), electromyogram (EMG), and electrooculogram (EOG) recordings. Setting: Rodent sleep laboratory. Participants: Fourteen male Arvicanthis ansorgei, aged 3 mo. Interventions: 12 h light (L):12 h dark (D) baseline condition, 24-h constant darkness, 6-h sleep deprivation. Measurements and Results: Wake and rapid eye movement (REM) sleep showed similar electrophysiological characteristics as nocturnal rodents. On average, animals spent 12.9 h ± 0.4 awake per 24-h cycle, of which 6.88 h ± 0.3 was during the light period. NREM sleep accounted for 9.63 h ± 0.4, which of 5.13 h ± 0.2 during dark period, and REM sleep for 89.9 min ± 6.7, which of 52.8 min ± 4.4 during dark period. The time-course of sleep and waking across the 12 h light:12 h dark was overall inverted to that observed in rats or mice, though with larger amounts of crepuscular activity at light and dark transitions. A dominant crepuscular regulation of sleep and waking persisted under constant darkness, showing the lack of a strong circadian drive in the absence of clock reinforcement by external cues, such as a running wheel. Conservation of the homeostatic regulation was confirmed with the observation of higher delta power following sustained waking periods and a 6-h sleep deprivation, with subsequent decrease during recovery sleep. Conclusions: Arvicanthis ansorgei is a valid diurnal rodent model for studying the regulatory mechanisms of sleep and so represents a valuable tool for further understanding the nocturnality/diurnality switch. Citation: Hubbard J, Ruppert E, Calvel L, Robin-Choteau L, Gropp CM

  20. Capacity for absorption of water-soluble secondary metabolites greater in birds than in rodents.

    Science.gov (United States)

    Karasov, William H; Caviedes-Vidal, Enrique; Bakken, Bradley Hartman; Izhaki, Ido; Samuni-Blank, Michal; Arad, Zeev

    2012-01-01

    Plant secondary metabolites (SMs) are pervasive in animal foods and potentially influence feeding behavior, interspecies interactions, and the distribution and abundance of animals. Some of the major classes of naturally occurring SMs in plants include many water-soluble compounds in the molecular size range that could cross the intestinal epithelium via the paracellular space by diffusion or solvent drag. There are differences among species in paracellular permeability. Using Middle Eastern rodent and avian consumers of fruits containing SMs, we tested the hypothesis that avian species would have significantly higher paracellular permeability than rodent species. Permeability in intact animals was assessed using standard pharmacological methodology to measure absorption of two radiolabeled, inert, neutral water-soluble probes that do not interact with intestinal nutrient transporters, L-arabinose (M(r) = 150.1 Da) and lactulose (M(r) = 342.3 Da). We also measured absorption of labeled 3-O-methyl-D-glucose (3OMD-glucose; M(r) = 194.2 Da), which is a nonmetabolized analogue of D-glucose that is passively absorbed through the paracellular space but also transported across the enterocyte membranes. Most glucose was absorbed by all species, but arabinose fractional absorption (f) was nearly three times higher in birds (1.03±0.17, n = 15 in two species) compared to rodents (0.37±0.06, n = 10 in two species) (Pbirds of arabinose exceeded those of 3OMD-glucose. Our findings are in agreement with previous work showing that the paracellular pathway is more prominent in birds relative to nonflying mammals, and suggests that birds may be challenged by greater absorption of water-soluble, dietary SMs. The increased expression of the paracellular pathway in birds hints at a tradeoff: the free energy birds gain by absorbing water-soluble nutrients passively may be offset by the metabolic demands placed on them to eliminate concomitantly absorbed SMs.

  1. The peculiarities of the masticator muscles in rodents

    Directory of Open Access Journals (Sweden)

    C. Spataru

    2013-06-01

    Full Text Available Comparative research concerning masticatory musculature in squirrel, muskrat and rabbit, take into account the emphasizing and morphofunctional interpretation of the osteomuscular particularities involved in the prehension and mastication processes. The development of the coronoid process on the muskrat and squirrel demonstrates the growing of the force when raising the mandible by increasing the action force attached to the temporal muscle, with insertion on the coronoid process. In comparison with that, in the case of rabbits, both the coronoid process and the temporal muscle are reduced. From a philogenetic point of view, it has been found that the species that have the articular condyle lowered at or under the level of the dental tables (carnivores present a greater pressure force between the dental tables. Analyzing this aspect of the rodents taken into discussion, we noticed the lowering of the articular condyle up to the inferior molars' plane, in the case of squirrels and muskrats, but through obliquity, namely through cranial caudal and dorsoventral movement. This peculiarity is emphasized through the analysis of the angle formed by the axis of the mandible recurved branch (passing through the mandibular condyle with the axis of the horizontal branch of the mandible, where it was noticed that along with the increase in the angle formed by the two axes, which becomes an obtuse 160 degree angle on the squirrel and 130 degrees on the muskrat, there is also a lowering of the articular condyle up to the molar level, while in the case of carnivores, the lowering of the condyle is done without the modification of the angle between the two axes, which measures approximately 90 degrees.

  2. Sperm competition, sperm numbers and sperm quality in muroid rodents.

    Science.gov (United States)

    Gómez Montoto, Laura; Magaña, Concepción; Tourmente, Maximiliano; Martín-Coello, Juan; Crespo, Cristina; Luque-Larena, Juan José; Gomendio, Montserrat; Roldan, Eduardo R S

    2011-03-25

    Sperm competition favors increases in relative testes mass and production efficiency, and changes in sperm phenotype that result in faster swimming speeds. However, little is known about its effects on traits that contribute to determine the quality of a whole ejaculate (i.e., proportion of motile, viable, morphologically normal and acrosome intact sperm) and that are key determinants of fertilization success. Two competing hypotheses lead to alternative predictions: (a) sperm quantity and quality traits co-evolve under sperm competition because they play complementary roles in determining ejaculate's competitive ability, or (b) energetic constraints force trade-offs between traits depending on their relevance in providing a competitive advantage. We examined relationships between sperm competition levels, sperm quantity, and traits that determine ejaculate quality, in a comparative study of 18 rodent species using phylogenetically controlled analyses. Total sperm numbers were positively correlated to proportions of normal sperm, acrosome integrity and motile sperm; the latter three were also significantly related among themselves, suggesting no trade-offs between traits. In addition, testes mass corrected for body mass (i.e., relative testes mass), showed a strong association with sperm numbers, and positive significant associations with all sperm traits that determine ejaculate quality with the exception of live sperm. An "overall sperm quality" parameter obtained by principal component analysis (which explained 85% of the variance) was more strongly associated with relative testes mass than any individual quality trait. Overall sperm quality was as strongly associated with relative testes mass as sperm numbers. Thus, sperm quality traits improve under sperm competition in an integrated manner suggesting that a combination of all traits is what makes ejaculates more competitive. In evolutionary terms this implies that a complex network of genetic and

  3. Molecular evidence of Rickettsia spp. in ixodid ticks and rodents in suburban, natural and rural habitats in Slovakia.

    Science.gov (United States)

    Minichová, Lenka; Hamšíková, Zuzana; Mahríková, Lenka; Slovák, Mirko; Kocianová, Elena; Kazimírová, Mária; Škultéty, Ľudovít; Štefanidesová, Katarína; Špitalská, Eva

    2017-03-24

    Natural foci of tick-borne spotted fever group (SFG) rickettsiae of public health concern have been found in Slovakia, but the role of rodents in their circulation is unclear. Ticks (Ixodes ricinus, Ixodes trianguliceps, Dermacentor marginatus, Dermacentor reticulatus, Haemaphysalis concinna and Haemaphysalis inermis) and tissues of rodents (Apodemus flavicollis, Apodemus sylvaticus, Myodes glareolus, Microtus arvalis, Microtus subterraneus and Micromys minutus) were examined for the presence of SFG rickettsiae and Coxiella burnetii by molecular methods. Suburban, natural and rural habitats were monitored to acquire information on the role of ticks and rodents in the agents' maintenance in various habitat types of Slovakia. The overall prevalence of rickettsial infection in questing I. ricinus and D. marginatus was 6.6% and 21.4%, respectively. Rickettsia helvetica, R. monacensis and non-identified rickettsial species were detected in I. ricinus, whereas R. slovaca and R. raoultii were identified in D. marginatus. Rickettsia spp.-infected I. ricinus occurred during the whole tick questing period. Rickettsia helvetica dominated (80.5%) followed by R. monacensis (6.5%). The species were present in all studied habitats. Rickettsia slovaca (66.7%) and R. raoultii (33.3%) were identified in D. marginatus from the rural habitat. Apodemus flavicollis was the most infested rodent species with I. ricinus, but My. glareolus carried the highest proportion of Rickettsia-positive I. ricinus larvae. Only 0.5% of rodents (A. flavicollis) and 5.2% of engorged I. ricinus removed from My. glareolus, A. flavicollis and M. arvalis were R. helvetica- and R. monacensis-positive. Coxiella burnetii was not detected in any of the tested samples. We hypothesize that rodents could play a role as carriers of infected ticks and contribute to the maintenance of rickettsial pathogens in natural foci. Long-term presence of SFG Rickettsia spp. was confirmed in questing ticks from different habitat

  4. Organisation and tyrosine hydroxylase and calretinin immunoreactivity in the main olfactory bulb of paca (Cuniculus paca): a large caviomorph rodent.

    Science.gov (United States)

    Sasahara, Tais Harumi de Castro; Leal, Leonardo Martins; Spillantini, Maria Grazia; Machado, Márcia Rita Fernandes

    2015-04-01

    The majority of neuroanatomical and chemical studies of the olfactory bulb have been performed in small rodents, such as rats and mice. Thus, this study aimed to describe the organisation and the chemical neuroanatomy of the main olfactory bulb (MOB) in paca, a large rodent belonging to the Hystricomorpha suborder and Caviomorpha infraorder. For this purpose, histological and immunohistochemical procedures were used to characterise the tyrosine hydroxylase (TH) and calretinin (CR) neuronal populations and their distribution. The paca MOB has eight layers: the olfactory nerve layer (ONL), the glomerular layer (GL), the external plexiform layer (EPL; subdivided into the inner and outer sublayers), the mitral cell layer (MCL), the internal plexiform layer (IPL), the granule cell layer (GCL), the periventricular layer and the ependymal layer. TH-ir neurons were found mostly in the GL, and moderate numbers of TH-ir neurons were scattered in the EPL. Numerous varicose fibres were distributed in the IPL and in the GCL. CR-ir neurons concentrated in the GL, around the base of the olfactory glomeruli. Most of the CR-ir neurons were located in the MCL, IPL and GCL. Some of the granule cells had an apical dendrite with a growth cone. The CR immunoreactivity was also observed in the ONL with olfactory nerves strongly immunostained. This study has shown that the MOB organisation in paca is consistent with the description in other mammals. The characterisation and distribution of the population of TH and CR in the MOB is not exclusively to this species. This large rodent shares common patterns to other caviomorph rodent, as guinea pig, and to the myomorph rodents, as mice, rats and hamsters.

  5. Lassa fever or lassa hemorrhagic fever risk to humans from rodent-borne zoonoses.

    Science.gov (United States)

    El-Bahnasawy, Mamdouh M; Megahed, Laila Abdel-Mawla; Abdalla Saleh, Hala Ahmed; Morsy, Tosson A

    2015-04-01

    Viral hemorrhagic fevers (VHFs) typically manifest as rapidly progressing acute febrile syndromes with profound hemorrhagic manifestations and very high fatality rates. Lassa fever, an acute hemorrhagic fever characterized by fever, muscle aches, sore throat, nausea, vomiting, diarrhea and chest and abdominal pain. Rodents are important reservoirs of rodent-borne zoonosis worldwide. Transmission rodents to humans occur by aerosol spread, either from the genus Mastomys rodents' excreta (multimammate rat) or through the close contact with infected patients (nosocomial infection). Other rodents of the genera Rattus, Mus, Lemniscomys, and Praomys are incriminated rodents hosts. Now one may ask do the rodents' ectoparasites play a role in Lassa virus zoonotic transmission. This paper summarized the update knowledge on LHV; hopping it might be useful to the clinicians, nursing staff, laboratories' personals as well as those concerned zoonoses from rodents and rodent control.

  6. Old World hantaviruses in rodents in New Orleans, Louisiana.

    Science.gov (United States)

    Cross, Robert W; Waffa, Bradley; Freeman, Ashley; Riegel, Claudia; Moses, Lina M; Bennett, Andrew; Safronetz, David; Fischer, Elizabeth R; Feldmann, Heinz; Voss, Thomas G; Bausch, Daniel G

    2014-05-01

    Seoul virus, an Old World hantavirus, is maintained in brown rats and causes a mild form of hemorrhagic fever with renal syndrome (HFRS) in humans. We captured rodents in New Orleans, Louisiana and tested them for the presence of Old World hantaviruses by reverse transcription polymerase chain reaction (RT-PCR) with sequencing, cell culture, and electron microscopy; 6 (3.4%) of 178 rodents captured--all brown rats--were positive for a Seoul virus variant previously coined Tchoupitoulas virus, which was noted in rodents in New Orleans in the 1980s. The finding of Tchoupitoulas virus in New Orleans over 25 years since its first discovery suggests stable endemicity in the city. Although the degree to which this virus causes human infection and disease remains unknown, repeated demonstration of Seoul virus in rodent populations, recent cases of laboratory-confirmed HFRS in some US cities, and a possible link with hypertensive renal disease warrant additional investigation in both rodents and humans.

  7. Protocol for production of a genetic cross of the rodent malaria parasites.

    Science.gov (United States)

    Pattaradilokrat, Sittiporn; Li, Jian; Su, Xin-zhuan

    2011-01-03

    Variation in response to antimalarial drugs and in pathogenicity of malaria parasites is of biologic and medical importance. Linkage mapping has led to successful identification of genes or loci underlying various traits in malaria parasites of rodents and humans. The malaria parasite Plasmodium yoelii is one of many malaria species isolated from wild African rodents and has been adapted to grow in laboratories. This species reproduces many of the biologic characteristics of the human malaria parasites; genetic markers such as microsatellite and amplified fragment length polymorphism (AFLP) markers have also been developed for the parasite. Thus, genetic studies in rodent malaria parasites can be performed to complement research on Plasmodium falciparum. Here, we demonstrate the techniques for producing a genetic cross in P. yoelii that were first pioneered by Drs. David Walliker, Richard Carter, and colleagues at the University of Edinburgh. Genetic crosses in P. yoelii and other rodent malaria parasites are conducted by infecting mice Mus musculus with an inoculum containing gametocytes of two genetically distinct clones that differ in phenotypes of interest and by allowing mosquitoes to feed on the infected mice 4 days after infection. The presence of male and female gametocytes in the mouse blood is microscopically confirmed before feeding. Within 48 hrs after feeding, in the midgut of the mosquito, the haploid gametocytes differentiate into male and female gametes, fertilize, and form a diploid zygote (Fig. 1). During development of a zygote into an ookinete, meiosis appears to occur. If the zygote is derived through cross-fertilization between gametes of the two genetically distinct parasites, genetic exchanges (chromosomal reassortment and cross-overs between the non-sister chromatids of a pair of homologous chromosomes; Fig. 2) may occur, resulting in recombination of genetic material at homologous loci. Each zygote undergoes two successive nuclear

  8. Sleep Deprivation and Caffeine Treatment Potentiate Photic Resetting of the Master Circadian Clock in a Diurnal Rodent.

    Science.gov (United States)

    Jha, Pawan Kumar; Bouâouda, Hanan; Gourmelen, Sylviane; Dumont, Stephanie; Fuchs, Fanny; Goumon, Yannick; Bourgin, Patrice; Kalsbeek, Andries; Challet, Etienne

    2017-04-19

    entrainment in nocturnal animals. How these stimuli act in diurnal species remains to be established. Our study in a diurnal rodent, the Grass rat, indicates that sleep deprivation in the early rest period induces phase delays of circadian locomotor activity rhythm. Contrary to nocturnal rodents, both sleep deprivation and caffeine-induced arousal potentiate the photic entrainment in a diurnal rodent. Such enhanced light-induced circadian responses could be relevant for developing chronotherapeutic strategies. Copyright © 2017 the authors 0270-6474/17/374343-16$15.00/0.

  9. Candidate Vectors and Rodent Hosts of Venezuelan Equine Encephalitis Virus, Chiapas, 2006–2007

    Science.gov (United States)

    Deardorff, Eleanor R.; Estrada-Franco, Jose G.; Freier, Jerome E.; Navarro-Lopez, Roberto; Da Rosa, Amelia Travassos; Tesh, Robert B.; Weaver, Scott C.

    2011-01-01

    Enzootic Venezuelan equine encephalitis virus (VEEV) has been known to occur in Mexico since the 1960s. The first natural equine epizootic was recognized in Chiapas in 1993 and since then, numerous studies have characterized the etiologic strains, including reverse genetic studies that incriminated a specific mutation that enhanced infection of epizootic mosquito vectors. The aim of this study was to determine the mosquito and rodent species involved in enzootic maintenance of subtype IE VEEV in coastal Chiapas. A longitudinal study was conducted over a year to discern which species and habitats could be associated with VEEV circulation. Antibody was rarely detected in mammals and virus was not isolated from mosquitoes. Additionally, Culex (Melanoconion) taeniopus populations were found to be spatially related to high levels of human and bovine seroprevalence. These mosquito populations were concentrated in areas that appear to represent foci of stable, enzootic VEEV circulation. PMID:22144461

  10. Population ecology of rodents of maize fields and grassland in central Ethiopia

    DEFF Research Database (Denmark)

    Bekel'e, Afework; Leirs, Herwig

    1997-01-01

    We report on the presence of rodents in grassland and maize fields in central Ethiopia, during the course of a 21-month study by means of removal and capture-recapture trapping. In both habitats, the small mammal fauna consisted of the same species but in different relative proportions: Arvicanthis...... dembeensis, Mastomys erythroleucus, Tatera robusta, Rattus rattus, Mus mahomet and Crocidura olivieri. A. dembeensis and M. erythroleucus were the dominant species. Densities were generally low throughout the study period, but at the end of the breeding season in the second year of the study, the numbers...... dynamics in the study area are linked to rainfall patterns and this information can be used to develop forecasting models....

  11. Effect of Removal of Woody Biomass after Clearcutting and Intercropping Switchgrass (Panicum virgatum with Loblolly Pine (Pinus taeda on Rodent Diversity and Populations

    Directory of Open Access Journals (Sweden)

    Matthew M. Marshall

    2012-01-01

    Full Text Available Plant-based feedstocks have long been considered viable, potential sources for biofuels. However, concerns regarding production effects may outweigh gains like carbon savings. Additional information is needed to understand environmental effects of growing feedstocks, including effects on wildlife communities and populations. We used a randomized and replicated experimental design to examine initial effects of biofuel feedstock treatment options, including removal of woody biomass after clearcutting and intercropping switchgrass (Panicum virgatum, on rodents to 2 years post-treatment in regenerating pine plantations in North Carolina, USA. Rodent community composition did not change with switchgrass production or residual biomass removal treatments. Further, residual biomass removal had no influence on rodent population abundances. However, Peromyscus leucopus was found in the greatest abundance and had the greatest survival in treatments without switchgrass. In contrast, abundance of invasive Mus musculus was greatest in switchgrass treatments. Other native species, such as Sigmodon hispidus, were not influenced by the presence of switchgrass. Our results suggest that planting of switchgrass, but not biomass removal, had species-specific effects on rodents at least 2 years post-planting in an intensively managed southern pine system. Determining ecological mechanisms underlying our observed species associations with switchgrass will be integral for understanding long-term sustainability of biofuels production in southern pine forest.

  12. Risky business: do native rodents use habitat and odor cues to manage predation risk in Australian deserts?

    Directory of Open Access Journals (Sweden)

    Emma E Spencer

    Full Text Available In open, arid environments with limited shelter there may be strong selection on small prey species to develop behaviors that facilitate predator avoidance. Here, we predicted that rodents should avoid predator odor and open habitats to reduce their probability of encounter with potential predators, and tested our predictions using a native Australian desert rodent, the spinifex hopping-mouse (Notomys alexis. We tested the foraging and movement responses of N. alexis to non-native predator (fox and cat odor, in sheltered and open macro- and microhabitats. Rodents did not respond to predator odor, perhaps reflecting the inconsistent selection pressure that is imposed on prey species in the desert environment due to the transience of predator-presence. However, they foraged primarily in the open and moved preferentially across open sand. The results suggest that N. alexis relies on escape rather than avoidance behavior when managing predation risk, with its bipedal movement probably allowing it to exploit open environments most effectively.

  13. Mass distribution and rotational inertia of "microtype" and "freely mobile" middle ear ossicles in rodents.

    Science.gov (United States)

    Lavender, Danielle; Taraskin, Sergei N; Mason, Matthew J

    2011-12-01

    The middle ears of seven species of rodents, including four hamster species, were examined under light microscopy and through micro-CT imaging. Hamsters were found to possess a spectrum of ossicular morphologies ranging from something approaching "freely mobile" (Mesocricetus) to something nearer the "microtype" (Cricetulus), although no hamster has an orbicular apophysis of the malleus. Rats, mice and Calomyscus were found to have typically microtype ossicles. To explore the functional effects of these morphological differences, CT scan data were used to calculate the magnitudes of the moments of inertia and positions of the centres of mass and principal rotational axes for the malleus-incus complexes. Microtype species were found to have much greater ossicular inertias, relative to size, about the "anatomical axis" extending between anterior process of the malleus and short process of the incus; ossicular centres of mass were displaced further from this axis. Calculated inertial values were then put into an existing model of middle ear function (Hemilä et al., 1995), in order to see whether the more accurate data would improve predictions of upper hearing limits. For the rat and mouse they did, but this was not so for the hamster Mesocricetus. This might indicate that the inner rather than the middle ear limits hearing in this species, or might simply reflect other shortcomings of the model. Functional differences appear to exist even among rodent ears of the same general type, but the adaptive significance of these differences remains enigmatic. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Anatomy and Histology of Rodent and Human Major Salivary Glands

    Science.gov (United States)

    Amano, Osamu; Mizobe, Kenichi; Bando, Yasuhiko; Sakiyama, Koji

    2012-01-01

    Major salivary glands of both humans and rodents consist of three pairs of macroscopic glands: parotid, submandibular, and sublingual. These glands secrete serous, mucous or mixed saliva via the proper main excretory ducts connecting the glandular bodies with the oral cavity. A series of discoveries about the salivary ducts in the 17th century by Niels Stensen (1638–1686), Thomas Wharton (1614–1673), and Caspar Bartholin (1655–1738) established the concept of exocrine secretion as well as salivary glands. Recent investigations have revealed the endocrine functions of parotin and a variety of cell growth factors produced by salivary glands. The present review aims to describe macroscopic findings on the major salivary glands of rodents and the microscopic differences between those of humans and rodents, which review should be of interest to those researchers studying salivary glands. PMID:23209333

  15. MR microscopy of the lung in small rodents

    International Nuclear Information System (INIS)

    Takahashi, Masaya; Kubo, Shigeto; Kiryu, Shigeru; Gee, James; Hatabu, Hiroto

    2007-01-01

    Understanding how the mammalian respiratory system works and how it changes in disease states and under the influence of drugs is frequently pursued in model systems such as small rodents. These have many advantages, including being easily obtained in large numbers as purebred strains. Studies in small rodents are valuable for proof of concept studies and for increasing our knowledge about disease mechanisms. Since the recent developments in the generation of genetically designed animal models of disease, one needs the ability to assess morphology and function in in vivo systems. In this article, we first review previous reports regarding thoracic imaging. We then discuss approaches to take in making use of small rodents to increase MR microscopic sensitivity for these studies and to establish MR methods for clinically relevant lung imaging

  16. Transplacental Nutrient Transport Mechanisms of Intrauterine Growth Restriction in Rodent Models and Humans

    Directory of Open Access Journals (Sweden)

    Elke Winterhager

    2017-11-01

    Full Text Available Although the causes of intrauterine growth restriction (IUGR have been intensively investigated, important information is still lacking about the role of the placenta as a link from adverse maternal environment to adverse pregnancy outcomes of IUGR and preterm birth. IUGR is associated with an increased risk of cardiovascular, metabolic, and neurological diseases later in life. Determination of the most important pathways that regulate transplacental transport systems is necessary for identifying marker genes as diagnostic tools and for developing drugs that target the molecular pathways. Besides oxygen, the main nutrients required for appropriate fetal development and growth are glucose, amino acids, and fatty acids. Dysfunction in transplacental transport is caused by impairments in both placental morphology and blood flow, as well as by factors such as alterations in the expression of insulin-like growth factors and changes in the mTOR signaling pathway leading to a change in nutrient transport. Animal models are important tools for systematically studying such complex events. Debate centers on whether the rodent placenta is an appropriate tool for investigating the alterations in the human placenta that result in IUGR. This review provides an overview of the alterations in expression and activity of nutrient transporters and alterations in signaling associated with IUGR and compares these findings in rodents and humans. In general, the data obtained by studies of the various types of rodent and human nutrient transporters are similar. However, direct comparison is complicated by the fact that the results of such studies are controversial even within the same species, making the interpretation of the results challenging. This difficulty could be due to the absence of guidelines of the experimental design and, especially in humans, the use of trophoblast cell culture studies instead of clinical trials. Nonetheless, developing new therapy

  17. The trophic responses of two different rodent-vector-plague systems to climate change.

    Science.gov (United States)

    Xu, Lei; Schmid, Boris V; Liu, Jun; Si, Xiaoyan; Stenseth, Nils Chr; Zhang, Zhibin

    2015-02-07

    Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  18. Factors affecting patterns of Amblyomma triste (Acari: Ixodidae) parasitism in a rodent host.

    Science.gov (United States)

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

    2015-07-30

    Here we offer a multivariable analysis that explores associations of different factors (i.e., environmental, host parameters, presence of other ectoparasites) with the interaction of Amblyomma triste immature stages and one of its main hosts in Argentina, the rodent Akodon azarae. Monthly and for two years, we captured and sampled rodents at 16 points located at 4 different sites in the Parana River Delta region. The analyses were conducted with Generalized Linear Mixed Models with a negative binomial response (counts of larvae or nymphs). The independent variables assessed were: (a) environmental: trapping year, season, presence of cattle; type of vegetation (natural grassland or implanted forest); rodent abundance; (b) host parameters: body length; sex; body condition; blood cell counts; natural antibody titres; and (c) co-infestation with other ectoparasites: other stage of A. triste; Ixodes loricatus; lice; mites; and fleas. Two-way interaction terms deemed a priori as relevant were also included in the analysis. Larvae were affected by all environmental variables assessed and by the presence of other ectoparasites (lice, fleas and other tick species). Host factors significantly associated with larval count were sex and levels of natural antibodies. Nymphs were associated with season, presence of cattle, body condition, body length and with burdens of I. loricatus. In most cases, the direction and magnitude of the associations were context-dependent (many interaction terms were significant). The findings of greater significance and implications of our study are two. Firstly, as burdens of A. triste larvae and nymphs were greater where cattle were present, and larval tick burdens were higher in implanted forests, silvopastoral practices developing in the region may affect the population dynamics of A. triste, and consequently the eco-epidemiology of Rickettsia parkeri. Secondly, strong associations and numerous interactions with other ectoparasites suggest that

  19. Transplacental Nutrient Transport Mechanisms of Intrauterine Growth Restriction in Rodent Models and Humans.

    Science.gov (United States)

    Winterhager, Elke; Gellhaus, Alexandra

    2017-01-01

    Although the causes of intrauterine growth restriction (IUGR) have been intensively investigated, important information is still lacking about the role of the placenta as a link from adverse maternal environment to adverse pregnancy outcomes of IUGR and preterm birth. IUGR is associated with an increased risk of cardiovascular, metabolic, and neurological diseases later in life. Determination of the most important pathways that regulate transplacental transport systems is necessary for identifying marker genes as diagnostic tools and for developing drugs that target the molecular pathways. Besides oxygen, the main nutrients required for appropriate fetal development and growth are glucose, amino acids, and fatty acids. Dysfunction in transplacental transport is caused by impairments in both placental morphology and blood flow, as well as by factors such as alterations in the expression of insulin-like growth factors and changes in the mTOR signaling pathway leading to a change in nutrient transport. Animal models are important tools for systematically studying such complex events. Debate centers on whether the rodent placenta is an appropriate tool for investigating the alterations in the human placenta that result in IUGR. This review provides an overview of the alterations in expression and activity of nutrient transporters and alterations in signaling associated with IUGR and compares these findings in rodents and humans. In general, the data obtained by studies of the various types of rodent and human nutrient transporters are similar. However, direct comparison is complicated by the fact that the results of such studies are controversial even within the same species, making the interpretation of the results challenging. This difficulty could be due to the absence of guidelines of the experimental design and, especially in humans, the use of trophoblast cell culture studies instead of clinical trials. Nonetheless, developing new therapy concepts for IUGR will

  20. Dim light at night increases immune function in Nile grass rats, a diurnal rodent.

    Science.gov (United States)

    Fonken, Laura K; Haim, Achikam; Nelson, Randy J

    2012-02-01

    With the widespread adoption of electrical lighting during the 20th century, human and nonhuman animals became exposed to high levels of light at night for the first time in evolutionary history. This divergence from the natural environment may have significant implications for certain ecological niches because of the important influence light exerts on the circadian system. For example, circadian disruption and nighttime light exposure are linked to changes in immune function. The majority of studies investigating the effects of light exposure and circadian disruption on the immune system use nocturnal rodents. In diurnal species, many hormones and immune parameters vary with secretion patterns 180° out of phase to those of nocturnal rodents. Thus, the authors investigated the effects of nighttime light exposure on immunocompetence in diurnal Nile grass rats (Arvicanthis niloticus). Rats were housed in either standard 14-h light (L):10-h dark (D) cycles with L ∼150 lux and D 0 lux or dim light at night (dLAN) cycles of LD 14:10 with L ∼150 lux and D 5 lux for 3 wks, then tested for plasma bactericidal capacity, as well as humoral and cell-mediated immune responses. Rats exposed to dLAN showed increased delayed-type hypersensitivity pinna swelling, which is consistent with enhanced cell-mediated immune function. dLAN rats similarly showed increased antibody production following inoculation with keyhole lymphocyte hemocyanin (KLH) and increased bactericidal capacity. Daytime corticosterone concentrations were elevated in grass rats exposed to nighttime dim light, which may have influenced immunological measures. Overall, these results indicate nighttime light affects immune parameters in a diurnal rodent.

  1. Prevalence of infection with Rickettsia helvetica in Ixodes ricinus ticks feeding on non-rickettsiemic rodent hosts in sylvatic habitats of west-central Poland.

    Science.gov (United States)

    Biernat, Beata; Stańczak, Joanna; Michalik, Jerzy; Sikora, Bożena; Wierzbicka, Anna

    2016-02-01

    Ixodes ricinus is the most prevalent and widely distributed tick species in European countries and plays a principal role in transmission of a wide range of microbial pathogens. It is also a main vector and reservoir of Rickettsia spp. of the spotted fever group with the infection level ranging in Poland from 1.3% to 11.4%. Nevertheless, little research has been conducted so far to identify reservoir hosts for these pathogens. A survey was undertaken to investigate the presence of Rickettsia spp. in wild small rodents and detached I. ricinus. Rodents, Apodemus flavicollis mice and Myodes glareolus voles were captured in typically sylvatic habitats of west-central Poland. Blood samples and collected ticks were analyzed by conventional, semi-nested and nested PCRs. Rickettsial species were determined by sequence analysis of obtained fragments of gltA and 16S rRNA genes. A total of 2339 immature I. ricinus (mostly larvae) were collected from 158 animals. Proportion of hosts carrying ticks was 84%, being higher for A. flavicollis than for M. glareolus. Rickettsia helvetica, the only species identified, was detected in 8% of 12 nymphs and in at least 10.7% (MIR) of 804 larvae investigated. Prevalence of infected ticks on both rodent species was comparable (10.8 vs. 9%). None of blood samples tested was positive for Rickettsia spp. The results showed that in sylvatic habitats the level of infestation with larval I. ricinus was higher in A. flavicollis mice in comparison with M. glareolus voles. They show that R. helvetica frequently occurred in ticks feeding on rodents. Positive immature ticks were collected from non-rickettsiemic hosts what might suggest a vertical route of their infection (transovarial and/or transstadial) or a very short-lasting rickettsiemia in rodents. A natural vertebrate reservoir host for R. helvetica remains to be determined. Copyright © 2015 Elsevier GmbH. All rights reserved.

  2. Kebutuhan Fisur Silen Gigi Posterior pada Murid-Murid Sekolah Dasar di Kota Madya Medan

    Directory of Open Access Journals (Sweden)

    Lina Natamiharja

    2015-10-01

    Full Text Available The application of pit and fissure sealants is widely accepted practice in carious prevention, these materials were developed in an effort to prevent plaque, bacteria and carbohydrates penetrating pits and fissures of the teeth. Fissure sealants are effective in preventing occlusal carious in 33 out of every 100 teeth. The purpose of this study was to determine the needs of fissure sealant among the children age 6-13 years old. This study was carried out in two elementary schools. Samples was taken by sistematic random sampling based on age and sex. The totals of samples was 430 children. The needs of fissure sealant in the molars were quite high (36,75%, the highest percentage was in the lower first molar (49,64%, followed by the lower second molar (42,92%. In the premolars the needs was low (8,02%, the greatest needs was in the lower second premolar (15,79% followed by upper first premolar (7,50%.

  3. In vivo efficacy of acyl CoA: diacylglycerol acyltransferase (DGAT) 1 inhibition in rodent models of postprandial hyperlipidemia.

    Science.gov (United States)

    King, Andrew J; Segreti, Jason A; Larson, Kelly J; Souers, Andrew J; Kym, Philip R; Reilly, Regina M; Collins, Christine A; Voorbach, Martin J; Zhao, Gang; Mittelstadt, Scott W; Cox, Bryan F

    2010-07-10

    Postprandial serum triglyceride concentrations have recently been identified as a major, independent risk factor for future cardiovascular events. As a result, postprandial hyperlipidemia has emerged as a potential therapeutic target. The purpose of this study was two-fold. Firstly, to describe and characterize a standardized model of postprandial hyperlipidemia in multiple rodent species; and secondly, apply these rodent models to the evaluation of a novel class of pharmacologic agent; acyl CoA:diacylglycerol acyltransferase (DGAT) 1 inhibitors. Serum triglycerides were measured before and for 4h after oral administration of a standardized volume of corn oil, to fasted C57BL/6, ob/ob, apoE(-/-) and CD-1 mice; Sprague-Dawley and JCR/LA-cp rats; and normolipidemic and hyperlipidemic hamsters. Intragastric administration of corn oil increased serum triglycerides in all animals evaluated, however the magnitude and time-course of the postprandial triglyceride excursion varied. The potent and selective DGAT-1 inhibitor A-922500 (0.03, 0.3 and 3 mg/kg, p.o.), dose-dependently attenuated the maximal postprandial rise in serum triglyceride concentrations in all species tested. At the highest dose of DGAT-1 inhibitor, the postprandial triglyceride response was abolished. This study provides a comprehensive characterization of the time-course of postprandial hyperlipidemia in rodents. In addition, the ability of DGAT-1 inhibitors to attenuate postprandial hyperlipidemia in multiple rodent models, including those that feature insulin resistance, is documented. Exaggerated postprandial hyperlipidemia is inherent to insulin-resistant states in humans and contributes to the substantially elevated cardiovascular risk observed in these patients. Therefore, by attenuating postprandial hyperlipidemia, DGAT-1 inhibition may represent a novel therapeutic approach to reduce cardiovascular risk. Copyright 2010 Elsevier B.V. All rights reserved.

  4. Effects of HZE irradiation on chemical neurotransmission in rodent hippocampus

    Science.gov (United States)

    Machida, Mayumi

    Space radiation represents a significant risk to the CNS (central nervous system) during space missions. Most harmful are the HZE (high mass, highly charged (Z), high energy) particles, e.g. 56Fe, which possess high ionizing ability, dense energy deposition pattern, and high penetrance. Accumulating evidence suggests that radiation has significant impact on cognitive functions. In ground-base experiments, HZE radiation induces pronounced deficits in hippocampus dependent learning and memory in rodents. However, the mechanisms underlying these impairments are mostly unknown. Exposure to HZE radiation elevates the level of oxidation, resulting in cell loss, tissue damage and functional deficits through direct ionization and generation of reactive oxygen species (ROS). When hippocampal slices were exposed to ROS, neuronal excitability was reduced. My preliminary results showed enhanced radio-vulnerability of the hippocampus and reduction in basal and depolarization-evoked [3H]-norepinephrine release after HZE exposure. These results raised the possibility that HZE radiation deteriorates cognitive function through radiation-induced impairments in hippocampal chemical neurotransmission, the hypothesis of this dissertation. In Aim 1 I have focused on the effects of HZE radiation on release of major neurotransmitter systems in the hippocampus. I have further extended my research on the levels of receptors of these systems in Aim 2. In Aim 3, I have studied the level of oxidation in membranes of my samples. My research reveals that HZE radiation significantly reduces hyperosmotic sucrose evoked [3H]-glutamate and [14C]-GABA release both three and six months post irradiation. The same radiation regimen also significantly enhances oxidative stress as indicated by increased levels of lipid peroxidation in the hippocampus, suggesting that increased levels of lipid peroxidation may play a role in reduction of neurotransmitter release. HZE radiation also significantly reduces

  5. Calodium (Capillaria hepaticum (Nematoda, Capillariidae in insular small rodent populations

    Directory of Open Access Journals (Sweden)

    Bugmyrin Sergey

    2014-12-01

    Full Text Available The data on the distribution of the nematode Calodium hepaticum (Bancroft 1893 Moravec 1982 (syn.: Capillaria hepatica, Hepaticola hepatica on the islands of Kizhi Archipelago are reported (N 62°00'; E 35°12'. Samples were collected on 18 islands and the mainland part of the Kizhi skerries region in the period from August 2005 till 2014. The method of partial helminthological dissection was applied to 346 specimens of rodents belonging to two species – the bank vole Myodes glareolus Schreber 1780 (301 spm. and the field vole Microtus agrestis Linnaeus 1761 (45 spm.. The prevalence and the abundance index of nematode were 16.6% and 1.1 in M. glareolus and 11.1%; 0.3 in M. agrestis, respectively. The highest prevalence and abundance of C. hepaticum were detected in mature voles. No sex-related differences were found. C. hepaticum was present in 12 of 19 sampling sites. On the islands where the sample number (host individuals was over 15, the highest prevalence and abundance values were 57% and 5.8 spm., respectively. Significant positive coefficients of correlation (Spearman’s and Pearson’s ones between nematode numbers and characteristics of the island were found in the pair «Prevalence – degree of isolation» (0.48 and 0.49. Single-factor analysis of variance showed that the size of the island had some effect on the nematode invasion prevalence and abundance. However, no significant regression relationship between the prevalence and abundance of nematodes and characteristics of an island was revealed by multivariate regression analysis (multiple regression: the coefficient of determination of the regression equation R2 < 0.3, and the regression coefficients were insignificant The reasons for high abundance of C. hepaticum in northern insular ecosystems are discussed. Possible key factors for the stable vitality of the parasite populations are: 1 favourable hydrothermal conditions of the soil in the shore (littoral zone; 2 the

  6. Relating appendicular skeletal variation of sigmodontine rodents to locomotion modes in a phylogenetic context.

    Science.gov (United States)

    Carvalho Coutinho, Ludmilla; Alves de Oliveira, João

    2017-10-01

    Sigmodontinae rodents constitute the second-largest subfamily among mammals. Alongside the taxonomic diversity, they are also ecologically diverse, exhibiting a wide array of locomotion modes, with semifossorial, terrestrial, semiaquatic, scansorial, arboreal, and saltatorial forms. To understand the ecomorphologic aspects that allow these rodents to display such locomotion diversity, we analyzed 35 qualitative characters of the appendicular skeleton (humerus, ulna, radius, scapula, femur, tibia, ilium, ischium and pubis) in 795 specimens belonging to 64 species, 34 genera and 10 tribes, representing all locomotion modes assigned to this subfamily. We performed a statistical analysis based upon the coefficient of trait differentiation to test the congruence of character states and the different locomotion modes. We also mapped characters states in a molecular phylogeny in order to reconstruct ancestral states and to evaluate how appendicular characters evolved within main lineages of Sigmodontinae radiation under a phylogenetic framework. The statistical analyses revealed six characters related to specific locomotion modes, except terrestrial. The mapping and parsimony ancestral states reconstruction identified two characters with phylogenetical signal and eight characters that are exclusively or more frequently recorded in certain modes of locomotion, four of them also detected by the statistical analysis. Notwithstanding the documented morphological variation, few changes characterize the transition to each of the locomotion modes, at least regarding the appendicular skeleton. This finding corroborates previous results that showed that sigmodontines exhibit an all-purpose appendicular morphology that allows them to use and explore a great variety of habitats. © 2017 Anatomical Society.

  7. Molecular analysis of a 11 700-year-old rodent midden from the Atacama Desert, Chile

    Science.gov (United States)

    Kuch, M.; Rohland, N.; Betancourt, J.L.; Latorre, C.; Steppan, S.; Poinar, H.N.

    2002-01-01

    DNA was extracted from an 11 700-year-old rodent midden from the Atacama Desert, Chile and the chloroplast and animal mitochondrial DNA (mtDNA) gene sequences were analysed to investigate the floral environment surrounding the midden, and the identity of the midden agent. The plant sequences, together with the macroscopic identifications, suggest the presence of 13 plant families and three orders that no longer exist today at the midden locality, and thus point to a much more diverse and humid climate 11 700 years ago. The mtDNA sequences suggest the presence of at least four different vertebrates, which have been putatively identified as a camelid (vicuna), two rodents (Phyllotis and Abrocoma), and a cardinal bird (Passeriformes). To identify the midden agent, DNA was extracted from pooled faecal pellets, three small overlapping fragments of the mitochondrial cytochrome b gene were amplified and multiple clones were sequenced. These results were analysed along with complete cytochrome b sequences for several modern Phyllotis species to place the midden sequence phylogenetically. The results identified the midden agent as belonging to an ancestral P. limatus. Today, P. limatus is not found at the midden locality but it can be found 100 km to the north, indicating at least a small range shift. The more extensive sampling of modern Phyllotis reinforces the suggestion that P. limatus is recently derived from a peripheral isolate.

  8. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent

    Science.gov (United States)

    Tachinardi, Patricia; Tøien, Øivind; Valentinuzzi, Veronica S.; Buck, C. Loren; Oda, Gisele A.

    2015-01-01

    Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti) are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel. PMID:26460828

  9. The NEWMEDS rodent touchscreen test battery for cognition relevant to schizophrenia.

    Science.gov (United States)

    Hvoslef-Eide, M; Mar, A C; Nilsson, S R O; Alsiö, J; Heath, C J; Saksida, L M; Robbins, T W; Bussey, T J

    2015-11-01

    The NEWMEDS initiative (Novel Methods leading to New Medications in Depression and Schizophrenia, http://www.newmeds-europe.com ) is a large industrial-academic collaborative project aimed at developing new methods for drug discovery for schizophrenia. As part of this project, Work package 2 (WP02) has developed and validated a comprehensive battery of novel touchscreen tasks for rats and mice for assessing cognitive domains relevant to schizophrenia. This article provides a review of the touchscreen battery of tasks for rats and mice for assessing cognitive domains relevant to schizophrenia and highlights validation data presented in several primary articles in this issue and elsewhere. The battery consists of the five-choice serial reaction time task and a novel rodent continuous performance task for measuring attention, a three-stimulus visual reversal and the serial visual reversal task for measuring cognitive flexibility, novel non-matching to sample-based tasks for measuring spatial working memory and paired-associates learning for measuring long-term memory. The rodent (i.e. both rats and mice) touchscreen operant chamber and battery has high translational value across species due to its emphasis on construct as well as face validity. In addition, it offers cognitive profiling of models of diseases with cognitive symptoms (not limited to schizophrenia) through a battery approach, whereby multiple cognitive constructs can be measured using the same apparatus, enabling comparisons of performance across tasks. This battery of tests constitutes an extensive tool package for both model characterisation and pre-clinical drug discovery.

  10. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent.

    Directory of Open Access Journals (Sweden)

    Patricia Tachinardi

    Full Text Available Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel.

  11. A rodent malarial model of Plasmodium berghei for the development ...

    African Journals Online (AJOL)

    A rodent malarial model of Plasmodium berghei for the development of pyrimethamine and sulphadoxine-pyrimethamine resistant malaria in mice. ... course approach with 125/6.25mg/kg S/P. The stability of resistance phenotypes, parasite pathogenic disposition and host leukocyte response were also investigated.

  12. seasonal population dynamics of rodents of mount chilalo, arsi ...

    African Journals Online (AJOL)

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    ABSTRACT: A study on seasonal population dynamics of rodents was carried out on Mount. Chilalo from .... vegetation growth, availability of food and water, and ... vegetation (3,300–4,200 masl) (Alemayehu. Mengistu, 1975; APEDO and ABRDP, 2004). The mountain is one of the Afrotropical biodiversity hotspots areas.

  13. Optimizing Cardiovascular Benefits of Exercise: A Review of Rodent Models

    Science.gov (United States)

    Davis, Brittany; Moriguchi, Takeshi; Sumpio, Bauer

    2013-01-01

    Although research unanimously maintains that exercise can ward off cardiovascular disease (CVD), the optimal type, duration, intensity, and combination of forms are yet not clear. In our review of existing rodent-based studies on exercise and cardiovascular health, we attempt to find the optimal forms, intensities, and durations of exercise. Using Scopus and Medline, a literature review of English language comparative journal studies of cardiovascular benefits and exercise was performed. This review examines the existing literature on rodent models of aerobic, anaerobic, and power exercise and compares the benefits of various training forms, intensities, and durations. The rodent studies reviewed in this article correlate with reports on human subjects that suggest regular aerobic exercise can improve cardiac and vascular structure and function, as well as lipid profiles, and reduce the risk of CVD. Findings demonstrate an abundance of rodent-based aerobic studies, but a lack of anaerobic and power forms of exercise, as well as comparisons of these three components of exercise. Thus, further studies must be conducted to determine a truly optimal regimen for cardiovascular health. PMID:24436579

  14. Factors associated with flea infestation among the different rodent ...

    African Journals Online (AJOL)

    Flea infection with the bacterium, Yersinia pestis is acquired from reservoirs which include several rodents and other small mammals. In areas that are endemic of plague, reservoirs of Y. pestis and various flea vectors are responsible for perpetuating existence of the disease. The objective of this cross sectional study was to ...

  15. Energetics and water relations ofN amib desert rodents

    African Journals Online (AJOL)

    and the possible effects of advective fog on the water balance of the .... Table 2 Energy balance of Namib desert rodents in the laboratory on a diet of air-dried bird seed and with, and with, ad lib water. .... responding mercury thermometer.

  16. The Revised Neurobehavioral Severity Scale (NSS-R) for Rodents.

    Science.gov (United States)

    Yarnell, Angela M; Barry, Erin S; Mountney, Andrea; Shear, Deborah; Tortella, Frank; Grunberg, Neil E

    2016-04-08

    Motor and sensory deficits are common following traumatic brain injury (TBI). Although rodent models provide valuable insight into the biological and functional outcomes of TBI, the success of translational research is critically dependent upon proper selection of sensitive, reliable, and reproducible assessments. Published literature includes various observational scales designed to evaluate post-injury functionality; however, the heterogeneity in TBI location, severity, and symptomology can complicate behavioral assessments. The importance of choosing behavioral outcomes that can be reliably and objectively quantified in an efficient manner is becoming increasingly important. The Revised Neurobehavioral Severity Scale (NSS-R) is a continuous series of specific, sensitive, and standardized observational tests that evaluate balance, motor coordination, and sensorimotor reflexes in rodents. The tasks follow a specific order designed to minimize interference: balance, landing, tail raise, dragging, righting reflex, ear reflex, eye reflex, sound reflex, tail pinch, and hindpaw pinch. The NSS-R has proven to be a reliable method differentiating brain-injured rodents from non-brain-injured rodents across many brain injury models. Copyright © 2016 John Wiley & Sons, Inc.

  17. Reproducibility and replicability of rodent phenotyping in preclinical studies

    NARCIS (Netherlands)

    Kafkafi, Neri; Agassi, Joseph; Chesler, Elissa J.; Crabbe, John C.; Crusio, Wim E.; Eilam, David; Gerlai, Robert; Golani, Ilan; Gomez-Marin, Alex; Heller, Ruth; Iraqi, Fuad; Jaljuli, Iman; Karp, Natasha A.; Morgan, Hugh; Nicholson, George; Pfaff, Donald W.; Richter, S. Helene; Stark, Philip B.; Stiedl, Oliver; Stodden, Victoria; Tarantino, Lisa M.; Tucci, Valter; Valdar, William; Williams, Robert W.; Würbel, Hanno; Benjamini, Yoav

    The scientific community is increasingly concerned with the proportion of published “discoveries” that are not replicated in subsequent studies. The field of rodent behavioral phenotyping was one of the first to raise this concern, and to relate it to other methodological issues: the complex

  18. STATUS OF COMMENSAL RODENT -BORNE DISEASES RESEARCH IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Lim Boo Liat

    2012-09-01

    Full Text Available Rodents yang terdapat di rumah-rumah maupun di lapangan mempunyai peranan penting dalam penyebaran penyakit terhadap manusia dan binatang. Dalam tulisan ini disajikan peninjauan kembali literatur tentang penyakit-penyakit yang ditularkan oleh binatang, seperti : plague, scrub and murine typhus, leptospirosis, schistosomiasis, angiostrongyliasis, yang biaya terdapat di Indonesia.

  19. Costs of rodent control in pine regeneration in California

    Science.gov (United States)

    Richard D. Cosens; David Tackle

    1950-01-01

    The control of seed-eating rodents, combined with the proper method of cutting and site preparation, appears essential to get the maximum results of natural seeding of pine. One method of control is by treating the area to be regenerated with lethal bait prior to seedfall. This note describes such a method and costs of treatment for the westside and eastside Sierran...

  20. Andes hantavirus variant in rodents, southern Amazon Basin, Peru.

    Science.gov (United States)

    Razuri, Hugo; Tokarz, Rafal; Ghersi, Bruno M; Salmon-Mulanovich, Gabriela; Guezala, M Claudia; Albujar, Christian; Mendoza, A Patricia; Tinoco, Yeny O; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah; Nichol, Stuart T; Hirschberg, David L; Lipkin, W Ian; Bausch, Daniel G; Montgomery, Joel M

    2014-02-01

    We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted.

  1. Andes Hantavirus Variant in Rodents, Southern Amazon Basin, Peru

    OpenAIRE

    Razuri, Hugo; Tokarz, Rafal; Ghersi, Bruno M.; Salmon-Mulanovich, Gabriela; Guezala, M. Claudia; Albujar, Christian; Mendoza, A. Patricia; Tinoco, Yeny O.; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah

    2014-01-01

    We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted.

  2. Fossil Rodents from Curaçao and Bonaire

    NARCIS (Netherlands)

    Hooijer, D.A.

    1959-01-01

    The fossil remains of rodents described in the present paper are from various localities. The large extinct musk rat Megalomys occurs in reddish-brown phosphatic “oolite” fillings of irregular cavities in a marine limestone found by Mr. P. H. DE BUISONJÉ in the north-western part of the Duivelsklip,

  3. Emmonsiosis of subterranean rodents (Bathyergidae, Spalacidae) in Africa and Israel

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Burda, H.; Scharff, A.; Heth, G.; Nevo, E.; Šumbera, R.; Peško, Juraj; Zima, Jan

    2005-01-01

    Roč. 43, č. 8 (2005), s. 691-697 ISSN 1369-3786 Grant - others:DAAD(DE) 323-PPP-sp Institutional research plan: CEZ:AV0Z60930519 Keywords : adiasporomycosis * rodents Subject RIV: EG - Zoology Impact factor: 1.422, year: 2005

  4. Rodent Research on the International Space Station - A Look Forward

    Science.gov (United States)

    Kapusta, A. B.; Smithwick, M.; Wigley, C. L.

    2014-01-01

    Rodent Research on the International Space Station (ISS) is one of the highest priority science activities being supported by NASA and is planned for up to two flights per year. The first Rodent Research flight, Rodent Research-1 (RR-1) validates the hardware and basic science operations (dissections and tissue preservation). Subsequent flights will add new capabilities to support rodent research on the ISS. RR-1 will validate the following capabilities: animal husbandry for up to 30 days, video downlink to support animal health checks and scientific analysis, on-orbit dissections, sample preservation in RNA. Later and formalin, sample transfer from formalin to ethanol (hindlimbs), rapid cool-down and subsequent freezing at -80 of tissues and carcasses, sample return and recovery. RR-2, scheduled for SpX-6 (Winter 20142015) will add the following capabilities: animal husbandry for up to 60 days, RFID chip reader for individual animal identification, water refill and food replenishment, anesthesia and recovery, bone densitometry, blood collection (via cardiac puncture), blood separation via centrifugation, soft tissue fixation in formalin with transfer to ethanol, and delivery of injectable drugs that require frozen storage prior to use. Additional capabilities are also planned for future flights and these include but are not limited to male mice, live animal return, and the development of experiment unique equipment to support science requirements for principal investigators that are selected for flight. In addition to the hardware capabilities to support rodent research the Crew Office has implemented a training program in generic rodent skills for all USOS crew members during their pre-assignment training rotation. This class includes training in general animal handling, euthanasia, injections, and dissections. The dissection portion of this training focuses on the dissection of the spleen, liver, kidney with adrenals, brain, eyes, and hindlimbs. By achieving and

  5. Semi-Autonomous Rodent Habitat for Deep Space Exploration

    Science.gov (United States)

    Alwood, J. S.; Shirazi-Fard, Y.; Pletcher, D.; Globus, R.

    2018-01-01

    NASA has flown animals to space as part of trailblazing missions and to understand the biological responses to spaceflight. Mice traveled in the Lunar Module with the Apollo 17 astronauts and now mice are frequent research subjects in LEO on the ISS. The ISS rodent missions have focused on unravelling biological mechanisms, better understanding risks to astronaut health, and testing candidate countermeasures. A critical barrier for longer-duration animal missions is the need for humans-in-the-loop to perform animal husbandry and perform routine tasks during a mission. Using autonomous or telerobotic systems to alleviate some of these tasks would enable longer-duration missions to be performed at the Deep Space Gateway. Rodent missions performed using the Gateway as a platform could address a number of critical risks identified by the Human Research Program (HRP), as well as Space Biology Program questions identified by NRC Decadal Survey on Biological and Physical Sciences in Space, (2011). HRP risk areas of potentially greatest relevance that the Gateway rodent missions can address include those related to visual impairment (VIIP) and radiation risks to central nervous system, cardiovascular disease, as well as countermeasure testing. Space Biology focus areas addressed by the Gateway rodent missions include mechanisms and combinatorial effects of microgravity and radiation. The objectives of the work proposed here are to 1) develop capability for semi-autonomous rodent research in cis-lunar orbit, 2) conduct key experiments for testing countermeasures against low gravity and space radiation. The hardware and operations system developed will enable experiments at least one month in duration, which potentially could be extended to one year in duration. To gain novel insights into the health risks to crew of deep space travel (i.e., exposure to space radiation), results obtained from Gateway flight rodents can be compared to ground control groups and separate groups

  6. Description of Medwayella independencia (Siphonaptera, Stivaliidae, a new species of flea from Mindanao Island, the Philippines and their phoretic mites, and miscellaneous flea records from the Malay Archipelago

    Directory of Open Access Journals (Sweden)

    Michael Hastriter

    2014-05-01

    Full Text Available Medwayella independencia, a new species of flea, is described from the tupaiid host Urogale everetti (Thomas from Mindanao Island, Philippines. Several other species of fleas are also recorded from the Philippines including a single male of Lentistivalius philippinensis Hastriter & Bush, 2013 (previously known only from two males, the bat fleas Thaumapsylla breviceps orientalis Smit and Thaumapsylla longiforceps Traub, a single unidentified female species of Macrostylophora Ewing collected from the murid Bullimus bagobos Mearns, and a pair of Medwayella robinsoni ssp. from Sundasciurus hoogstraali (Sanborn from Busuanga Island, Philippines. Representatives of Medwayella Traub, 1972 and Macrostylophora have not previously been recorded from the Philippines. A key to the male sex of Medwayella is provided. Phoretic mites of the genus Psylloglyphus (family Winterschmidtiidae were present under the abdominal sclerites of several male and female specimens of M. independencia. This is the second report of a phoretic mite on a species of Medwayella Traub. The co-evolutionary implications between phoretic mites and fleas are discussed.

  7. The response of human and rodent cells to hyperthermia

    International Nuclear Information System (INIS)

    Roizin-Towle, L.; Pirro, J.P.

    1991-01-01

    Inherent cellular radiosensitivity in vitro has been shown to be a good predictor of human tumor response in vivo. In contrast, the importance of the intrinsic thermosensitivity of normal and neoplastic human cells as a factor in the responsiveness of human tumors to adjuvant hyperthermia has never been analyzed systematically. A comparison of thermal sensitivity and thermo-radiosensitization in four rodent and eight human-derived cell lines was made in vitro. Arrhenius plots indicated that the rodent cells were more sensitive to heat killing than the human, and the break-point was 0.5 degrees C higher for the human than rodent cells. The relationship between thermal sensitivity and the interaction of heat with X rays at low doses was documented by thermal enhancement ratios (TER's). Cells received either a 1 hr exposure to 43 degrees C or a 20 minute treatment at 45 degrees C before exposure to 300 kVp X rays. Thermal enhancement ratios ranged from 1.0 to 2.7 for human cells heated at 43 degrees C and from 2.1 to 5.3 for heat exposures at 45 degrees C. Thermal enhancement ratios for rodent cells were generally 2 to 3 times higher than for human cells, because of the fact that the greater thermosensitivity of rodent cells results in a greater enhancement of radiation damage. Intrinsic thermosensitivity of human cells has relevance to the concept of thermal dose; intrinsic thermo-radiosensitization of a range of different tumor cells is useful in documenting the interactive effects of radiation combined with heat

  8. Nutritional Evaluation of NASA's Rodent Food Bar Diet

    Science.gov (United States)

    Barrett, Joyce E.; Yu, Diane S.; Dalton, Bonnie P.

    2000-01-01

    Tests are being conducted on NASA's rodent Food Bar in preparation for long-term use as the rat and mouse diet aboard the International Space Station. Nutritional analyses are performed after the bars are manufactured and then repeated periodically to determine nutritional stability. The primary factors analyzed are protein, ash, fat, fiber, moisture, amino acids, fatty acids, and minerals. Nutrient levels are compared to values published in the National Research Council's dietary requirements for rodents, and also to those contained in several commonly used commercial rodent lab diets. The Food Bar is manufactured from a powdered diet to which moisture is added as it is processed through an extruder. The bars are dipped into potassium sorbate, vacuum-sealed, and irradiated. In order to determine nutrient changes during extrusion and irradiation, the powdered diet, the non-irradiated bars, and the irradiated bars are all analyzed. We have observed lower values for some nutrients (iodine, vitamin K, and iron) in the Food Bars compared with NRC requirements. Many nutrients in the Food Bars are contained at a higher level than levels in the NRC requirements. An additional factor we are investigating is the 26% moisture level in the Food Bars, which drops to about 15% within a week, compared to a stable 10% moisture in many standard lab chow diets. In addition to the nutritional analyses, the food bar is being fed to several strains of rats and mice, and feeding study and necropsy results are being observed (Barrett et al, unpublished data). Information from the nutritional analyses and from the rodent studies will enable us to recommend the formulation that will most adequately meet the rodent Food Bar requirements for long-term use aboard the Space Station.

  9. Tularemia, plague, yersiniosis, and Tyzzer’s disease in wild rodents and lagomorphs in Canada: A review

    Science.gov (United States)

    Wobeser, Gary; Campbell, G. Douglas; Dallaire, André; McBurney, Scott

    2009-01-01

    Information related to infection of wild rodents or lagomorphs in Canada by Francisella tularensis, Yersinia pestis, other Yersinia spp., and Clostridium piliforme was searched for this study. Reports on tularemia in humans linked to these species came from diagnostic databases, literature, wildlife health specialists, and public health agencies. Tularemia has been diagnosed in 8 species of wild rodent and 2 species in the genus Lepus in Canada. Tularemia occurred in wild animals, or in humans associated with these species, in all jurisdictions except the Yukon and Nunavut. Tularemia was diagnosed most frequently in beaver, muskrats, and snowshoe hares, and although tularemia is closely linked to cottontail rabbits in the USA, it has not been reported in cottontails in Canada. Tularemia in humans was associated with muskrats and hares more commonly than with beaver. Plague was diagnosed in bushy-tailed woodrats in British Columbia in 1988. Based on surveys, Y. pestis may occur enzootically in southern Alberta, Saskatchewan, and British Columbia. Infection with Yersinia pseudotuberculosis and Y. enterocolitica has been diagnosed in beaver, muskrats, and snowshoe hares in many provinces. Tyzzer’s disease has been diagnosed in muskrats in British Columbia, Saskatchewan, Ontario, and Quebec and in snowshoe hares in Ontario. Infection with these bacteria is likely much more frequent than indicated by diagnostic records. PMID:20190973

  10. Disturbance by an endemic rodent in an arid shrubland is a habitat filter: effects on plant invasion and taxonomical, functional and phylogenetic community structure.

    Science.gov (United States)

    Escobedo, Víctor M; Rios, Rodrigo S; Salgado-Luarte, Cristian; Stotz, Gisela C; Gianoli, Ernesto

    2017-03-01

    Disturbance often drives plant invasion and may modify community assembly. However, little is known about how these modifications of community patterns occur in terms of taxonomic, functional and phylogenetic structure. This study evaluated in an arid shrubland the influence of disturbance by an endemic rodent on community functional divergence and phylogenetic structure as well as on plant invasion. It was expected that disturbance would operate as a habitat filter favouring exotic species with short life cycles. Sixteen plots were sampled along a disturbance gradient caused by the endemic fossorial rodent Spalacopus cyanus , measuring community parameters and estimating functional divergence for life history traits (functional dispersion index) and the relative contribution to functional divergence of exotic and native species. The phylogenetic signal (Pagel's lambda) and phylogenetic community structure (mean phylogenetic distance and mean nearest taxon phylogenetic distance) were also estimated. The use of a continuous approach to the disturbance gradient allowed the identification of non-linear relationships between disturbance and community parameters. The relationship between disturbance and both species richness and abundance was positive for exotic species and negative for native species. Disturbance modified community composition, and exotic species were associated with more disturbed sites. Disturbance increased trait convergence, which resulted in phylogenetic clustering because traits showed a significant phylogenetic signal. The relative contribution of exotic species to functional divergence increased, while that of natives decreased, with disturbance. Exotic and native species were not phylogenetically distinct. Disturbance by rodents in this arid shrubland constitutes a habitat filter over phylogeny-dependent life history traits, leading to phylogenetic clustering, and drives invasion by favouring species with short life cycles. Results can be

  11. Long-term Potentiation Decay and Poor Long-lasting Memory Process in the Wild Rodents Proechimys from Brazil's Amazon Rainforest.

    Science.gov (United States)

    Guimarães Marques, Marcia J; Reyes-Garcia, Selvin Z; Marques-Carneiro, José E; Lopes-Silva, Leonardo B; Andersen, Monica L; Cavalheiro, Esper A; Scorza, Fulvio A; Scorza, Carla A

    2018-01-01

    Proechimys are small terrestrial rodents from Amazon rainforest. Each animal species is adapted to a specific environment in which the animal evolved therefore without comparative approaches unique characteristics of distinct species cannot be fully recognized. Laboratory rodents are exceedingly inbred strains dissociated from their native habitats and their fundamental ecological aspects are abstracted. Thus, the employment of exotic non-model species can be informative and complement conventional animal models. With the aim of promoting comparative studies between the exotic wildlife populations in the laboratory and traditional rodent model, we surveyed a type of synaptic plasticity intimately related to memory encoding in animals. Using theta-burst paradigm, in vitro long-term potentiation (LTP) in the CA1 subfield of hippocampal slices was assessed in the Amazon rodents Proechimys and Wistar rats. Memory, learning and anxiety were investigated through the plus-maze discriminative avoidance task (PM-DAT) and object recognition test. In PM-DAT, both animal species were submitted to two test sessions (3-h and 24-h) after the conditioning training. Proechimys exhibited higher anxiety-like behavior in the training session but during test sessions both species exhibited similar patterns of anxiety-related behavior. After 3-h of the training, Proechimys and Wistar spent significantly less time in the aversive enclosed arm than in the non-aversive arm. But, at 24-h after training, Wistar rats remained less time in the aversive closed arm in comparison with the non-aversive one, while Proechimys rodents spent the same amount of time in both enclosed arms. In the object recognition test, both species were evaluated at 24-h after the acquisition session and similar findings than those of the PM-DAT (24-h) were obtained, suggesting that long-term memory duration did not persist for 24-h in the Amazon rodent. Field excitatory post-synaptic potentials recordings revealed

  12. Long-term Potentiation Decay and Poor Long-lasting Memory Process in the Wild Rodents Proechimys from Brazil’s Amazon Rainforest

    Directory of Open Access Journals (Sweden)

    Marcia J. Guimarães Marques

    2018-01-01

    Full Text Available Proechimys are small terrestrial rodents from Amazon rainforest. Each animal species is adapted to a specific environment in which the animal evolved therefore without comparative approaches unique characteristics of distinct species cannot be fully recognized. Laboratory rodents are exceedingly inbred strains dissociated from their native habitats and their fundamental ecological aspects are abstracted. Thus, the employment of exotic non-model species can be informative and complement conventional animal models. With the aim of promoting comparative studies between the exotic wildlife populations in the laboratory and traditional rodent model, we surveyed a type of synaptic plasticity intimately related to memory encoding in animals. Using theta-burst paradigm, in vitro long-term potentiation (LTP in the CA1 subfield of hippocampal slices was assessed in the Amazon rodents Proechimys and Wistar rats. Memory, learning and anxiety were investigated through the plus-maze discriminative avoidance task (PM-DAT and object recognition test. In PM-DAT, both animal species were submitted to two test sessions (3-h and 24-h after the conditioning training. Proechimys exhibited higher anxiety-like behavior in the training session but during test sessions both species exhibited similar patterns of anxiety-related behavior. After 3-h of the training, Proechimys and Wistar spent significantly less time in the aversive enclosed arm than in the non-aversive arm. But, at 24-h after training, Wistar rats remained less time in the aversive closed arm in comparison with the non-aversive one, while Proechimys rodents spent the same amount of time in both enclosed arms. In the object recognition test, both species were evaluated at 24-h after the acquisition session and similar findings than those of the PM-DAT (24-h were obtained, suggesting that long-term memory duration did not persist for 24-h in the Amazon rodent. Field excitatory post-synaptic potentials

  13. Long-term Potentiation Decay and Poor Long-lasting Memory Process in the Wild Rodents Proechimys from Brazil’s Amazon Rainforest

    Science.gov (United States)

    Guimarães Marques, Marcia J.; Reyes-Garcia, Selvin Z.; Marques-Carneiro, José E.; Lopes-Silva, Leonardo B.; Andersen, Monica L.; Cavalheiro, Esper A.; Scorza, Fulvio A.; Scorza, Carla A.

    2018-01-01

    Proechimys are small terrestrial rodents from Amazon rainforest. Each animal species is adapted to a specific environment in which the animal evolved therefore without comparative approaches unique characteristics of distinct species cannot be fully recognized. Laboratory rodents are exceedingly inbred strains dissociated from their native habitats and their fundamental ecological aspects are abstracted. Thus, the employment of exotic non-model species can be informative and complement conventional animal models. With the aim of promoting comparative studies between the exotic wildlife populations in the laboratory and traditional rodent model, we surveyed a type of synaptic plasticity intimately related to memory encoding in animals. Using theta-burst paradigm, in vitro long-term potentiation (LTP) in the CA1 subfield of hippocampal slices was assessed in the Amazon rodents Proechimys and Wistar rats. Memory, learning and anxiety were investigated through the plus-maze discriminative avoidance task (PM-DAT) and object recognition test. In PM-DAT, both animal species were submitted to two test sessions (3-h and 24-h) after the conditioning training. Proechimys exhibited higher anxiety-like behavior in the training session but during test sessions both species exhibited similar patterns of anxiety-related behavior. After 3-h of the training, Proechimys and Wistar spent significantly less time in the aversive enclosed arm than in the non-aversive arm. But, at 24-h after training, Wistar rats remained less time in the aversive closed arm in comparison with the non-aversive one, while Proechimys rodents spent the same amount of time in both enclosed arms. In the object recognition test, both species were evaluated at 24-h after the acquisition session and similar findings than those of the PM-DAT (24-h) were obtained, suggesting that long-term memory duration did not persist for 24-h in the Amazon rodent. Field excitatory post-synaptic potentials recordings revealed

  14. Rodent-borne Trypanosoma from cities and villages of Niger and Nigeria: A special role for the invasive genus Rattus?

    Science.gov (United States)

    Tatard, C; Garba, M; Gauthier, P; Hima, K; Artige, E; Dossou, D K H J; Gagaré, S; Genson, G; Truc, P; Dobigny, G

    2017-07-01

    Although they are known to sometimes infect humans, atypical trypanosomes are very poorly documented, especially in Africa where one lethal case has yet been described. Here we conducted a survey of rodent-borne Trypanosoma in 19 towns and villages of Niger and Nigeria, with a special emphasis on Niamey, the capital city of Niger. The 1298 rodents that were captured yielded 189 qPCR-positive animals from 14 localities, thus corresponding to a 14.6% overall prevalence. Rats, especially black rats, displayed particularly elevated prevalence (27.4%), with some well sampled sites showing 40-50% and up to 68.8% of Trypanosoma-carrying individuals. Rattus were also characterized by significantly lower Ct values than in the other non-Rattus species. DNA sequences could be obtained for 43 rodent-borne Trypanosoma and corresponded to 41 T. lewisi (all from Rattus) and 2 T. microti (from Cricetomys gambianus). These results, together with data compiled from the available literature, suggest that Rattus may play a particular role for the maintaining and circulation of Trypanosoma, especially T. lewisi, in Africa. Taken into account its strong abilities to invade coastal and inland regions of the continent, we believe that this genus deserves a particular attention in regards to potentially under-looked but emerging atypical trypanosome-related diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Tannin concentration enhances seed caching by scatter-hoarding rodents: An experiment using artificial ‘seeds’

    Science.gov (United States)

    Wang, Bo; Chen, Jin

    2008-11-01

    Tannins are very common among plant seeds but their effects on the fate of seeds, for example, via mediation of the feeding preferences of scatter-hoarding rodents, are poorly understood. In this study, we created a series of artificial 'seeds' that only differed in tannin concentration and the type of tannin, and placed them in a pine forest in the Shangri-La Alpine Botanical Garden, Yunnan Province of China. Two rodent species ( Apodemus latronum and A. chevrieri) showed significant preferences for 'seeds' with different tannin concentrations. A significantly higher proportion of seeds with low tannin concentration were consumed in situ compared with seeds with a higher tannin concentration. Meanwhile, the tannin concentration was significantly positively correlated with the proportion of seeds cached. The different types of tannin (hydrolysable tannin vs condensed tannin) did not differ significantly in their effect on the proportion of seeds eaten in situ vs seeds cached. Tannin concentrations had no significant effect on the distance that cached seeds were carried, which suggests that rodents may respond to different seed traits in deciding whether or not to cache seeds and how far they will transport seeds.

  16. Investigating the Influence of Climate Changes on Rodent Communities at a Regional-Scale (MIS 1-3, Southwestern France.

    Directory of Open Access Journals (Sweden)

    Aurélien Royer

    Full Text Available Terrestrial ecosystems have continuously evolved throughout the Late Pleistocene and the Holocene, deeply affected by both progressive environmental and climatic modifications, as well as by abrupt and large climatic changes such as the Heinrich or Dansgaard-Oeschger events. Yet, the impacts of these different events on terrestrial mammalian communities are poorly known, as is the role played by potential refugia on geographical species distributions. This study examines community changes in rodents of southwestern France between 50 and 10 ky BP by integrating 94 dated faunal assemblages coming from 37 archaeological sites. This work reveals that faunal distributions were modified in response to abrupt and brief climatic events, such as Heinrich events, without actually modifying the rodent community on a regional scale. However, the succession of events which operated between the Late Pleistocene and the Holocene gradually led to establishing a new rodent community at the regional scale, with intermediate communities occurring between the Bølling and the Allerød.

  17. Glutamate and GABA in autism spectrum disorder-a translational magnetic resonance spectroscopy study in man and rodent models.

    Science.gov (United States)

    Horder, Jamie; Petrinovic, Marija M; Mendez, Maria A; Bruns, Andreas; Takumi, Toru; Spooren, Will; Barker, Gareth J; Künnecke, Basil; Murphy, Declan G

    2018-05-25

    Autism spectrum disorder (ASD) is a pervasive neurodevelopmental syndrome with a high human and economic burden. The pathophysiology of ASD is largely unclear, thus hampering development of pharmacological treatments for the core symptoms of the disorder. Abnormalities in glutamate and GABA signaling have been hypothesized to underlie ASD symptoms, and may form a therapeutic target, but it is not known whether these abnormalities are recapitulated in humans with ASD, as well as in rodent models of the disorder. We used translational proton magnetic resonance spectroscopy ([1H]MRS) to compare glutamate and GABA levels in adult humans with ASD and in a panel of six diverse rodent ASD models, encompassing genetic and environmental etiologies. [1H]MRS was performed in the striatum and the medial prefrontal cortex, of the humans, mice, and rats in order to allow for direct cross-species comparisons in specific cortical and subcortical brain regions implicated in ASD. In humans with ASD, glutamate concentration was reduced in the striatum and this was correlated with the severity of social symptoms. GABA levels were not altered in either brain region. The reduction in striatal glutamate was recapitulated in mice prenatally exposed to valproate, and in mice and rats carrying Nlgn3 mutations, but not in rodent ASD models with other etiologies. Our findings suggest that glutamate/GABA abnormalities in the corticostriatal circuitry may be a key pathological mechanism in ASD; and may be linked to alterations in the neuroligin-neurexin signaling complex.

  18. Ocorrência de Babesia sp em pequenos roedores no Brasil Occurrence of Babesia sp in small rodents in Brazil

    Directory of Open Access Journals (Sweden)

    G.S. Gazeta

    2004-12-01

    Full Text Available Foi analisada a ocorrência de babesiose em pequenos roedores nos municípios de Silva Jardim e Nova lguaçu, Estado do Rio de Janeiro. Foram capturados 44 roedores de seis espécies diferentes e entre eles a prevalência da infecção foi de 27,3%. Rattus norvegicus foi considerado o principal reservatório (50,0% e Oligoryzomys nigripes como novo hospedeiro para Babesia sp. Este foi o primeiro relato de Babesia sp. em roedores no Brasil. A freqüência de roedores positivos e o risco de infecção dos roedores não diferiram entre as áreas estudadas.The occurrence of babesiosis was studied in 44 small rodents of six species captured in Silva Jardim and Nova lguaçu counties, State of Rio de Janeiro, Brazil. The prevalence of injection was 27.3%. Rattus norvegicus was considered as the main reservoir and Oligoryzomys nigripes as a new host to Babesia sp. The frequency and the risk of rodent infection were considered equal among the studied areas. This is the first report of Babesia sp in small rodents in Brazil.

  19. Infection of Rodents by Orientia tsutsugamushi, the Agent of Scrub Typhus in Relation to Land Use in Thailand

    Directory of Open Access Journals (Sweden)

    Kittipong Chaisiri

    2017-10-01

    Full Text Available The relationship between land use structures and occurrence of scrub typhus agent, Orientia tsutsugamushi infection in small wild mammals was conducted in three provinces of Thailand: Buriram, Loei, and Nan. Orientia tsutsugamushi detection was performed using 16S ribosomal DNA (rDNA amplicon sequencing approach using Miseq Illumina platform. In total, 387 animals (rodents and shrews were examined for the bacterium infection. The 16S rDNA sequences of the bacterium were found in nine animals from Bandicota savilei, Berylmys bowersi, Leopoldamys edwardsi, Rattus exulans, R. tanezumi, and Rattus sp. phylogenetic clade 3, yielding 2.3% infection rate, with two new rodent species infected by the bacterium in Thailand: B. bowersi and L. edwardsi. Using a Generalized Linear Mixed Model (GLMM and Random Forest analyses for investigating the association between human-land use and occurrence of the bacterium, forest habitat appeared as a strong explicative variable of rodent infection, meaning that O. tsutsugamushi-infected animals were more likely found in forest-covered habitats. In terms of public health implementation, our results suggest that heterogenous forested areas including forest-converted agricultural land, reforestation areas, or fallow are potential habitats for O. tsutsugamushi transmission. Further understanding of population dynamics of the vectors and their hosts in these habitats could be beneficial for the prevention of this neglected zoonotic disease.

  20. Habitat requirements and burrowing depths of rodents in relation to shallow waste burial sites

    Energy Technology Data Exchange (ETDEWEB)

    Gano, K.A.; States, J.B.

    1982-05-01

    The purpose of this paper is to provide a review of the literature and summarize information on factors affecting habitat selection and maximum recorded burrowing depths for representative small mammals that we consider most likely to inhibit waste burial sites in arid and semi-arid regions of the West. The information is intended for waste management designers who need to know what to expect from small mammals that may be present at a particular site. Waste repositories oculd be designed to exclude the deep burrowing rodents of a region by creating an unattractive habitat over the waste. Summaries are given for habitat requirements of each group along with generalized modifications that could be employed to deter habitation. Representatives from the major groups considered to be deep burrowers are discussed. Further, detailed information about a particular species can be obtained from the references cited.

  1. Habitat requirements and burrowing depths of rodents in relation to shallow waste burial sites

    International Nuclear Information System (INIS)

    Gano, K.A.; States, J.B.

    1982-05-01

    The purpose of this paper is to provide a review of the literature and summarize information on factors affecting habitat selection and maximum recorded burrowing depths for representative small mammals that we consider most likely to inhibit waste burial sites in arid and semi-arid regions of the West. The information is intended for waste management designers who need to know what to expect from small mammals that may be present at a particular site. Waste repositories oculd be designed to exclude the deep burrowing rodents of a region by creating an unattractive habitat over the waste. Summaries are given for habitat requirements of each group along with generalized modifications that could be employed to deter habitation. Representatives from the major groups considered to be deep burrowers are discussed. Further, detailed information about a particular species can be obtained from the references cited

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Illuminating the evolution of equids and rodents with next-generation sequencing of ancient specimens

    DEFF Research Database (Denmark)

    Mouatt, Julia Thidamarth Vilstrup

    enrichment methods and the massive throughput and latest advances within DNA sequencing, the field of ancient DNA has flourished in later years. Those advances have even enabled the sequencing of complete genomes from the past, moving the field into genomic sciences. In this thesis we have used these latest......The sequencing of ancient DNA provides perspectives on the genetic history of past populations and extinct species. However, ancient DNA research presents specific limitations mostly due to DNA survival, damage and contamination. Yet with stringent laboratory procedures, the sensitivity of target...... developments within ancient DNA research, including target enrichment capture and Next-Generation Sequencing, to address a range of evolutionary questions related to two major mammalian groups, equids and rodents. In particular we have resolved phylogenetic relationships within equids using complete mitochond...

  4. Genotoxic effects in wild rodents (Rattus rattus and Mus musculus) in an open coal mining area.

    Science.gov (United States)

    León, Grethel; Pérez, Lyda Espitia; Linares, Juan Carlos; Hartmann, Andreas; Quintana, Milton

    2007-06-15

    Coal is a mixture of a variety of compounds containing mutagenic and carcinogenic polycyclic aromatic hydrocarbons. Exposure to coal is considered as an important non-cellular and cellular source of reactive oxygen species that can induce DNA damage. In addition, spontaneous combustion can occur in coal mining areas, further releasing compounds with detrimental effects on the environment. In this study the comet assay was used to investigate potential genotoxic effects of coal mining activities in peripheral blood cells of the wild rodents Rattus rattus and Mus musculus. The study was conducted in a coal mining area of the Municipio de Puerto Libertador, South West of the Departamento de Cordoba, Colombia. Animals from two areas in the coal mining zone and a control area located in the Municipio de Lorica were investigated. The results showed evidence that exposure to coal results in elevated primary DNA lesions in blood cells of rodents. Three different parameters for DNA damage were assessed, namely, DNA damage index, migration length and percentage damaged cells. All parameters showed statistically significantly higher values in mice and rats from the coal mining area in comparison to the animals from the control area. The parameter "DNA Damage Index" was found to be most sensitive and to best indicate a genotoxic hazard. Both species investigated were shown to be sensitive indicators of environmental genotoxicity caused by coal mining activities. In summary, our study constitutes the first investigation of potential genotoxic effects of open coal mining carried out in Puerto Libertador. The investigations provide a guide for measures to evaluate genotoxic hazards, thereby contributing to the development of appropriate measures and regulations for more careful operations during coal mining.

  5. Ventilatory function assessment in safety pharmacology: Optimization of rodent studies using normocapnic or hypercapnic conditions

    International Nuclear Information System (INIS)

    Goineau, Sonia; Rompion, Sonia; Guillaume, Philippe; Picard, Sandra

    2010-01-01

    Although the whole body plethysmography for unrestrained animals is the most widely used method to assess the respiratory risk of new drugs in safety pharmacology, non-appropriate experimental conditions may mask deleterious side effects of some substances. If stimulant or bronchodilatory effects can be easily evidenced in rodents under standard experimental conditions, i.e. normal air breathing and diurnal phase, drug-induced respiratory depression remains more difficult to detect. This study was aimed at comparing the responsiveness of Wistar rats, Duncan Hartley guinea-pigs or BALB/c mice to the respiratory properties of theophylline (50 or 100 mg/kg p.o.) or morphine (30 mg/kg i.p.) under varying conditions (100% air versus 5% CO 2 -enriched air, light versus dark day phase), in order to select the most appropriate experimental conditions to each species for safety airway investigations. Our results showed that under normocapnia the ventilatory depressant effects of morphine can be easily evidenced in mice, slightly observed in guinea-pigs and not detected in rats in any day phase. Slight hypercapnic conditions enhanced the responsiveness of rats to morphine but not that of guinea-pigs and importantly they did not blunt the airway responsiveness of rats to the stimulation and bronchodilation evoked by theophylline, the most widely used reference agent in safety pharmacology studies. In conclusion, hypercapnic conditions associated with the non-invasive whole body plethysmography should be considered for optimizing the assessment of both the ventilatory depressant potential of morphine-like substances or the respiratory stimulant effects of new drugs in the rat, the most extensively used species in rodent safety and toxicological investigations.

  6. Characterizing low dose and dose rate effects in rodent and human neural stem cells exposed to proton and gamma irradiation

    Directory of Open Access Journals (Sweden)

    Bertrand P. Tseng

    2013-01-01

    Full Text Available Past work has shown that exposure to gamma rays and protons elicit a persistent oxidative stress in rodent and human neural stem cells (hNSCs. We have now adapted these studies to more realistic exposure scenarios in space, using lower doses and dose rates of these radiation modalities, to further elucidate the role of radiation-induced oxidative stress in these cells. Rodent neural stem and precursor cells grown as neurospheres and human neural stem cells grown as monolayers were subjected to acute and multi-dosing paradigms at differing dose rates and analyzed for changes in reactive oxygen species (ROS, reactive nitrogen species (RNS, nitric oxide and superoxide for 2 days after irradiation. While acute exposures led to significant changes in both cell types, hNSCs in particular, exhibited marked and significant elevations in radiation-induced oxidative stress. Elevated oxidative stress was more significant in hNSCs as opposed to their rodent counterparts, and hNSCs were significantly more sensitive to low dose exposures in terms of survival. Combinations of protons and γ-rays delivered as lower priming or higher challenge doses elicited radioadaptive changes that were associated with improved survival, but in general, only under conditions where the levels of reactive species were suppressed compared to cells irradiated acutely. Protective radioadaptive effects on survival were eliminated in the presence of the antioxidant N-acetylcysteine, suggesting further that radiation-induced oxidative stress could activate pro-survival signaling pathways that were sensitive to redox state. Data corroborates much of our past work and shows that low dose and dose rate exposures elicit significant changes in oxidative stress that have functional consequences on survival.

  7. Proteomics of Trypanosoma evansi infection in rodents.

    Science.gov (United States)

    Roy, Nainita; Nageshan, Rishi Kumar; Pallavi, Rani; Chakravarthy, Harshini; Chandran, Syama; Kumar, Rajender; Gupta, Ashok Kumar; Singh, Raj Kumar; Yadav, Suresh Chandra; Tatu, Utpal

    2010-03-22

    Trypanosoma evansi infections, commonly called 'surra', cause significant economic losses to livestock industry. While this infection is mainly restricted to large animals such as camels, donkeys and equines, recent reports indicate their ability to infect humans. There are no World Animal Health Organization (WAHO) prescribed diagnostic tests or vaccines available against this disease and the available drugs show significant toxicity. There is an urgent need to develop improved methods of diagnosis and control measures for this disease. Unlike its related human parasites T. brucei and T. cruzi whose genomes have been fully sequenced T. evansi genome sequence remains unavailable and very little efforts are being made to develop improved methods of prevention, diagnosis and treatment. With a view to identify potential diagnostic markers and drug targets we have studied the clinical proteome of T. evansi infection using mass spectrometry (MS). Using shot-gun proteomic approach involving nano-lc Quadrupole Time Of Flight (QTOF) mass spectrometry we have identified over 160 proteins expressed by T. evansi in mice infected with camel isolate. Homology driven searches for protein identification from MS/MS data led to most of the matches arising from related Trypanosoma species. Proteins identified belonged to various functional categories including metabolic enzymes; DNA metabolism; transcription; translation as well as cell-cell communication and signal transduction. TCA cycle enzymes were strikingly missing, possibly suggesting their low abundances. The clinical proteome revealed the presence of known and potential drug targets such as oligopeptidases, kinases, cysteine proteases and more. Previous proteomic studies on Trypanosomal infections, including human parasites T. brucei and T. cruzi, have been carried out from lab grown cultures. For T. evansi infection this is indeed the first ever proteomic study reported thus far. In addition to providing a glimpse into the

  8. Proteomics of Trypanosoma evansi infection in rodents.

    Directory of Open Access Journals (Sweden)

    Nainita Roy

    2010-03-01

    Full Text Available Trypanosoma evansi infections, commonly called 'surra', cause significant economic losses to livestock industry. While this infection is mainly restricted to large animals such as camels, donkeys and equines, recent reports indicate their ability to infect humans. There are no World Animal Health Organization (WAHO prescribed diagnostic tests or vaccines available against this disease and the available drugs show significant toxicity. There is an urgent need to develop improved methods of diagnosis and control measures for this disease. Unlike its related human parasites T. brucei and T. cruzi whose genomes have been fully sequenced T. evansi genome sequence remains unavailable and very little efforts are being made to develop improved methods of prevention, diagnosis and treatment. With a view to identify potential diagnostic markers and drug targets we have studied the clinical proteome of T. evansi infection using mass spectrometry (MS.Using shot-gun proteomic approach involving nano-lc Quadrupole Time Of Flight (QTOF mass spectrometry we have identified over 160 proteins expressed by T. evansi in mice infected with camel isolate. Homology driven searches for protein identification from MS/MS data led to most of the matches arising from related Trypanosoma species. Proteins identified belonged to various functional categories including metabolic enzymes; DNA metabolism; transcription; translation as well as cell-cell communication and signal transduction. TCA cycle enzymes were strikingly missing, possibly suggesting their low abundances. The clinical proteome revealed the presence of known and potential drug targets such as oligopeptidases, kinases, cysteine proteases and more.Previous proteomic studies on Trypanosomal infections, including human parasites T. brucei and T. cruzi, have been carried out from lab grown cultures. For T. evansi infection this is indeed the first ever proteomic study reported thus far. In addition to providing a

  9. Rodents from the Upper Miocene Tuğlu Formation (Çankırı Basin, Central Anatolia, Turkey)

    OpenAIRE

    Joniak, Peter; de Bruijn, Hans

    2015-01-01

    The upper Miocene assemblages of rodents collected from two layers of the type section of the Tuğlu Formation (Çankırı Basin, Central Anatolia, Turkey) are described. The assemblage from the lower level is considerably less diverse than that from the upper level. It contains Progonomys together with Megacricetodon, which is a very unusual association. The assemblage from the upper layer shows a relatively high diversity with four species of Gliridae instead of only one in the lower layer. Apa...

  10. Endangered Species

    Science.gov (United States)

    EPA's Endangered Species Protection Program helps promote recovery of listed species. The ESPP determines if pesticide use in a geographic area may affect any listed species. Find needed limits on pesticide use in Endangered Species Protection Bulletins.

  11. Of mice and women: rodent models of placental malaria

    DEFF Research Database (Denmark)

    Hviid, Lars; Marinho, Claudio R F; Staalsoe, Trine

    2010-01-01

    Pregnant women are at increased malaria risk. The infections are characterized by placental accumulation of infected erythrocytes (IEs) with adverse consequences for mother and baby. Placental IE sequestration in the intervillous space is mediated by variant surface antigens (VSAs) selectively...... expressed in placental malaria (PM) and specific for chondroitin sulfate A (CSA). In Plasmodium falciparum, these VSA(PM) appear largely synonymous with the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family variant VAR2CSA. As rodent malaria parasites do not possess PfEMP1 homologs......, the usefulness of experimental mouse PM models remains controversial. However, many features of murine and human PM are similar, including involvement of VSAs analogous to PfEMP1. It thus appears that rodent model studies can further the understanding of VSA-dependent malaria pathogenesis and immunity....

  12. A glimpse on the pattern of rodent diversification

    DEFF Research Database (Denmark)

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

    2012-01-01

    BACKGROUND:Development of phylogenetic methods that do not rely on fossils for the study of evolutionary processes through time have revolutionized the field of evolutionary biology and resulted in an unprecedented expansion of our knowledge about the tree of life. These methods have helped to shed...... molecular works. A relaxed molecular clock dating approach provided a time framework for speciation events. We found that the Myomorpha clade shows a greater degree of variation in diversification rates than Sciuroidea, Caviomorpha, Castorimorpha and Anomaluromorpha. We identified a number of shifts...... imbalances and the time line we discuss the potential role of different diversification factors that might have shaped the rodents radiation. CONCLUSIONS:The present glimpse on the diversification pattern of rodents can be used for further comparative meta-analyses. Muroid lineages have a greater degree...

  13. Hantavirus Immunology of Rodent Reservoirs: Current Status and Future Directions

    Directory of Open Access Journals (Sweden)

    Tony Schountz

    2014-03-01

    Full Text Available Hantaviruses are hosted by rodents, insectivores and bats. Several rodent-borne hantaviruses cause two diseases that share many features in humans, hemorrhagic fever with renal syndrome in Eurasia or hantavirus cardiopulmonary syndrome in the Americas. It is thought that the immune response plays a significant contributory role in these diseases. However, in reservoir hosts that have been closely examined, little or no pathology occurs and infection is persistent despite evidence of adaptive immune responses. Because most hantavirus reservoirs are not model organisms, it is difficult to conduct meaningful experiments that might shed light on how the viruses evade sterilizing immune responses and why immunopathology does not occur. Despite these limitations, recent advances in instrumentation and bioinformatics will have a dramatic impact on understanding reservoir host responses to hantaviruses by employing a systems biology approach to identify important pathways that mediate virus/reservoir relationships.

  14. Methods for Dissecting Motivation and Related Psychological Processes in Rodents.

    Science.gov (United States)

    Ward, Ryan D

    2016-01-01

    Motivational impairments are increasingly recognized as being critical to functional deficits and decreased quality of life in patients diagnosed with psychiatric disease. Accordingly, much preclinical research has focused on identifying psychological and neurobiological processes which underlie motivation . Inferring motivation from changes in overt behavioural responding in animal models, however, is complicated, and care must be taken to ensure that the observed change is accurately characterized as a change in motivation , and not due to some other, task-related process. This chapter discusses current methods for assessing motivation and related psychological processes in rodents. Using an example from work characterizing the motivational impairments in an animal model of the negative symptoms of schizophrenia, we highlight the importance of careful and rigorous experimental dissection of motivation and the related psychological processes when characterizing motivational deficits in rodent models . We suggest that such work is critical to the successful translation of preclinical findings to therapeutic benefits for patients.

  15. Effects of parasitism on host reproductive investment in a rodent-flea system: host litter size matters.

    Science.gov (United States)

    Warburton, Elizabeth M; Khokhlova, Irina S; Dlugosz, Elizabeth M; Der Mescht, Luther Van; Krasnov, Boris R

    2017-02-01

    Parents may alter offspring phenotype depending on the type of environment they encounter. Parasitism is a common stressor; therefore, maternal reproductive investment could change in response to parasitic infection. However, few experiments have investigated the relationship between parasitism and maternal investment, whereas earlier field studies provided contradictory evidence. We investigated number, sex ratio, and growth of offspring in two rodent species, solitary altricial Meriones crassus and social precocial Acomys cahirinus, exposed to parasitism by fleas Xenopsylla ramesis and Parapulex chephrenis. No effect of treatment on litter size or sex ratio of a litter was found in either rodent species. Flea parasitism was found to affect pre-weaning body mass gain in M. crassus, but not in A. cahirinus pups. Furthermore, it appeared that female M. crassus invested resources into their offspring differently in dependence of litter size. In small litters (1-3 offspring), pups from infested females gained more body mass before weaning than pups from uninfested mothers. However, this trend was reversed in females with large litters indicating that parasitized females have a finite amount of resources with which to provision their young. Thus, M. crassus mothers parasitized by fleas seemed to receive some sort of external cues (e.g., stress caused by infestation) that prompted them to alter offspring provisioning, depending on species-specific possibilities and constraints. Therefore, parasites could be a mediator of environmentally induced maternal effects and offspring provisioning may have adaptive value against parasitism.

  16. Elucidating transmission dynamics and host-parasite-vector relationships for rodent-borne Bartonella spp. in Madagascar

    Directory of Open Access Journals (Sweden)

    Cara E. Brook

    2017-09-01

    Full Text Available Bartonella spp. are erythrocytic bacteria transmitted via arthropod vectors, which infect a broad range of vertebrate hosts, including humans. We investigated transmission dynamics and host-parasite-vector relationships for potentially zoonotic Bartonella spp. in invasive Rattus rattus hosts and associated arthropod ectoparasites in Madagascar. We identified five distinct species of Bartonella (B. elizabethae 1, B. elizabethae 2, B. phoceensis 1, B. rattimassiliensis 1, and B. tribocorum 1 infecting R. rattus rodents and their ectoparasites. We fit standard epidemiological models to species-specific age-prevalence data for the four Bartonella spp. with sufficient data, thus quantifying age-structured force of infection. Known zoonotic agents, B. elizabethae 1 and 2, were best described by models exhibiting high forces of infection in early age class individuals and allowing for recovery from infection, while B. phoceensis 1 and B. rattimassiliensis 1 were best fit by models of lifelong infection without recovery and substantially lower forces of infection. Nested sequences of B. elizabethae 1 and 2 were recovered from rodent hosts and their Synopsyllus fonquerniei and Xenopsylla cheopsis fleas, with a particularly high prevalence in the outdoor-dwelling, highland-endemic S. fonquerniei. These findings expand on force of infection analyses to elucidate the ecological niche of the zoonotic Bartonella elizabethae complex in Madagascar, hinting at a potential vector role for S. fonquerniei. Our analyses underscore the uniqueness of such ecologies for Bartonella species, which pose a variable range of potential zoonotic threats.

  17. Citral reduces nociceptive and inflammatory response in rodents

    OpenAIRE

    Quintans-Júnior, Lucindo J.; Guimarães, Adriana G.; Santana, Marilia T. de; Araújo, Bruno E.S.; Moreira, Flávia V.; Bonjardim, Leonardo R.; Araújo, Adriano A. S.; Siqueira, Jullyana S.; Antoniolli, Ângelo R.; Botelho, Marco A.; Almeida, Jackson R. G. S.; Santos, Márcio R. V.

    2011-01-01

    Citral (CIT), which contains the chiral enantiomers, neral (cis) and geranial (trans), is the majority monoterpene from Lippia alba and Cymbopogon citratus. The present study aimed to evaluate CIT for antinociceptive and anti-inflammatory activities in rodents. Antinociceptive and anti-inflammatory effects were studied by measuring nociception through acetic acid and formalin tests, while inflammation was verified by inducing peritonitis and paw edema with carrageenan. All tested doses of CIT...

  18. Miniature wireless recording and stimulation system for rodent behavioural testing

    Science.gov (United States)

    Pinnell, R. C.; Dempster, J.; Pratt, J.

    2015-12-01

    Objective. Elucidation of neural activity underpinning rodent behaviour has traditionally been hampered by the use of tethered systems and human involvement. Furthermore the combination of deep-brain stimulation (DBS) and various neural recording modalities can lead to complex and time-consuming laboratory setups. For studies of this type, novel tools are required to drive forward this research. Approach. A miniature wireless system weighing 8.5 g (including battery) was developed for rodent use that combined multichannel DBS and local-field potential (LFP) recordings. Its performance was verified in a working memory task that involved 4-channel fronto-hippocampal LFP recording and bilateral constant-current fimbria-fornix DBS. The system was synchronised with video-tracking for extraction of LFP at discrete task phases, and DBS was activated intermittently at discrete phases of the task. Main results. In addition to having a fast set-up time, the system could reliably transmit continuous LFP at over 8 hours across 3-5 m distances. During the working memory task, LFP pertaining to discrete task phases was extracted and compared with well-known neural correlates of active exploratory behaviour in rodents. DBS could be wirelessly activated/deactivated at any part of the experiment during EEG recording and transmission, allowing for a seamless integration of this modality. Significance. The wireless system combines a small size with a level of robustness and versatility that can greatly simplify rodent behavioural experiments involving EEG recording and DBS. Designed for versatility and simplicity, the small size and low-cost of the system and its receiver allow for enhanced portability, fast experimental setup times, and pave the way for integration with more complex behaviour.

  19. Role of rodents in transmission of Salmonella and Campylobacter

    OpenAIRE

    Meerburg, Dr BG; Kijlstra, Prof dr A

    2007-01-01

    Salmonella and Campylobacter are generally regarded as the most important food-borne pathogens in the world. Reduction or elimination of these pathogens in the first part of the food chain (on the farm) is important to prevent disease among consumers of animal products. In organic farming, elimination becomes more difficult, as food animals are allowed outdoors and have easy access to potential sources of hazardous pathogens. Whilst rodents are often associated by organic farmers with infr...

  20. Social memories in rodents: Methods, mechanisms and modulation by stress

    OpenAIRE

    van der Kooij MA; Sandi C.

    2011-01-01

    Intact social memory forms the basis of meaningful interactions between individuals. Many factors can modulate the quality of social memory, and these have been studied in detail in rodents. Social memory, however, cannot be considered a single entity. The term social memory reflects different processes, such as social recognition of a novel conspecific individual and social learning (or 'learning from others'). This review summarizes the findings obtained with behavioral paradigms that were ...

  1. Morphological evolution, ecological diversification and climate change in rodents

    OpenAIRE

    Renaud, Sabrina; Michaux, Jacques; Schmidt, Daniela N; Aguilar, Jean-Pierre; Mein, Pierre; Auffray, Jean-Christophe

    2005-01-01

    Among rodents, the lineage from Progonomys hispanicus to Stephanomys documents a case of increasing size and dental specialization during an approximately 9 Myr time-interval. On the contrary, some contemporaneous generalist lineages like Apodemus show a limited morphological evolution. Dental shape can be related to diet and can be used to assess the ecological changes along the lineages. Consequently, size and shape of the first upper molar were measured in order to quantify the patterns of...

  2. Performance Analysis of Exam Gloves Used for Aseptic Rodent Surgery

    Science.gov (United States)

    LeMoine, Dana M; Bergdall, Valerie K; Freed, Carrie

    2015-01-01

    Aseptic technique includes the use of sterile surgical gloves for survival surgeries in rodents to minimize the incidence of infections. Exam gloves are much less expensive than are surgical gloves and may represent a cost-effective, readily available option for use in rodent surgery. This study examined the effectiveness of surface disinfection of exam gloves with 70% isopropyl alcohol or a solution of hydrogen peroxide and peracetic acid (HP–PA) in reducing bacterial contamination. Performance levels for asepsis were met when gloves were negative for bacterial contamination after surface disinfection and sham ‘exertion’ activity. According to these criteria, 94% of HP–PA-disinfected gloves passed, compared with 47% of alcohol-disinfected gloves. In addition, the effect of autoclaving on the integrity of exam gloves was examined, given that autoclaving is another readily available option for aseptic preparation. Performance criteria for glove integrity after autoclaving consisted of: the ability to don the gloves followed by successful simulation of wound closure and completion of stretch tests without tearing or observable defects. Using this criteria, 98% of autoclaved nitrile exam gloves and 76% of autoclaved latex exam gloves met performance expectations compared with the performance of standard surgical gloves (88% nitrile, 100% latex). The results of this study support the use of HP–PA-disinfected latex and nitrile exam gloves or autoclaved nitrile exam gloves as viable cost-effective alternatives to sterile surgical gloves for rodent surgeries. PMID:26045458

  3. Inbred or Outbred? Genetic Diversity in Laboratory Rodent Colonies

    Science.gov (United States)

    Brekke, Thomas D.; Steele, Katherine A.; Mulley, John F.

    2017-01-01

    Nonmodel rodents are widely used as subjects for both basic and applied biological research, but the genetic diversity of the study individuals is rarely quantified. University-housed colonies tend to be small and subject to founder effects and genetic drift; so they may be highly inbred or show substantial genetic divergence from other colonies, even those derived from the same source. Disregard for the levels of genetic diversity in an animal colony may result in a failure to replicate results if a different colony is used to repeat an experiment, as different colonies may have fixed alternative variants. Here we use high throughput sequencing to demonstrate genetic divergence in three isolated colonies of Mongolian gerbil (Meriones unguiculatus) even though they were all established recently from the same source. We also show that genetic diversity in allegedly “outbred” colonies of nonmodel rodents (gerbils, hamsters, house mice, deer mice, and rats) varies considerably from nearly no segregating diversity to very high levels of polymorphism. We conclude that genetic divergence in isolated colonies may play an important role in the “replication crisis.” In a more positive light, divergent rodent colonies represent an opportunity to leverage genetically distinct individuals in genetic crossing experiments. In sum, awareness of the genetic diversity of an animal colony is paramount as it allows researchers to properly replicate experiments and also to capitalize on other genetically distinct individuals to explore the genetic basis of a trait. PMID:29242387

  4. Isolating human DNA repair genes using rodent-cell mutants

    International Nuclear Information System (INIS)

    Thompson, L.H.; Weber, C.A.; Brookman, K.W.; Salazar, E.P.; Stewart, S.A.; Mitchell, D.L.

    1987-01-01

    The DNA repair systems of rodent and human cells appear to be at least as complex genetically as those in lower eukaryotes and bacteria. The use of mutant lines of rodent cells as a means of identifying human repair genes by functional complementation offers a new approach toward studying the role of repair in mutagenesis and carcinogenesis. In each of six cases examined using hybrid cells, specific human chromosomes have been identified that correct CHO cell mutations affecting repair of damage from uv or ionizing radiations. This finding suggests that both the repair genes and proteins may be virtually interchangeable between rodent and human cells. Using cosmid vectors, human repair genes that map to chromosome 19 have cloned as functional sequences: ERCC2 and XRCC1. ERCC1 was found to have homology with the yeast excision repair gene RAD10. Transformants of repair-deficient cell lines carrying the corresponding human gene show efficient correction of repair capacity by all criteria examined. 39 refs., 1 fig., 1 tab

  5. Performance analysis of exam gloves used for aseptic rodent surgery.

    Science.gov (United States)

    LeMoine, Dana M; Bergdall, Valerie K; Freed, Carrie

    2015-05-01

    Aseptic technique includes the use of sterile surgical gloves for survival surgeries in rodents to minimize the incidence of infections. Exam gloves are much less expensive than are surgical gloves and may represent a cost-effective, readily available option for use in rodent surgery. This study examined the effectiveness of surface disinfection of exam gloves with 70% isopropyl alcohol or a solution of hydrogen peroxide and peracetic acid (HP-PA) in reducing bacterial contamination. Performance levels for asepsis were met when gloves were negative for bacterial contamination after surface disinfection and sham 'exertion' activity. According to these criteria, 94% of HP-PA-disinfected gloves passed, compared with 47% of alcohol-disinfected gloves. In addition, the effect of autoclaving on the integrity of exam gloves was examined, given that autoclaving is another readily available option for aseptic preparation. Performance criteria for glove integrity after autoclaving consisted of: the ability to don the gloves followed by successful simulation of wound closure and completion of stretch tests without tearing or observable defects. Using this criteria, 98% of autoclaved nitrile exam gloves and 76% of autoclaved latex exam gloves met performance expectations compared with the performance of standard surgical gloves (88% nitrile, 100% latex). The results of this study support the use of HP-PA-disinfected latex and nitrile exam gloves or autoclaved nitrile exam gloves as viable cost-effective alternatives to sterile surgical gloves for rodent surgeries.

  6. Fire ignition during laser surgery in pet rodents

    Directory of Open Access Journals (Sweden)

    Collarile Tommaso

    2012-09-01

    Full Text Available Abstract Background Laser surgery is an attractive alternative to other means of section device in terms of tissue inflammation and interaction, which has been extensively used in human and veterinary medicine. Although accidental ignition during laser surgeries is sporadically reported in human medical literature, to the authors’ knowledge this is the first report regarding laser-dependent fire ignition during surgery in veterinary medicine. Case presentation Two rodents, a 13-month old, 27-gram, male pet mouse (Mus musculus and a 1-year old, female Russian hamster (Phodopus sungorus, underwent surgical removal of masses with diode laser. During the surgical procedures fires ignited from the face masks. The mouse presented severe burns on the head and both forelimbs, it was hospitalized and approximately 2 months after surgery burns were resolved. The hamster presented severe burns on the face and the proximal regions of the body. At 72 hours from the accident the hamster was euthanized. Conclusion The present report suggests that fire ignition is a potential life-threatening complication of laser surgery in non-intubated rodents maintained under volatile anesthesia. High oxygen concentrations, the presence of combustible, and the narrowness of the surgical field with the face mask during laser surgery on rodents are risk factors for fire ignition.

  7. The valproic acid-induced rodent model of autism.

    Science.gov (United States)

    Nicolini, Chiara; Fahnestock, Margaret

    2018-01-01

    Autism is a lifelong neurodevelopmental disorder characterized by impairments in social communication and interaction and by repetitive patterns of behavior, interests and activities. While autism has a strong genetic component, environmental factors including toxins, pesticides, infection and drugs are known to confer autism susceptibility, likely by inducing epigenetic changes. In particular, exposure to valproic acid (VPA) during pregnancy has been demonstrated to increase the risk of autism in children. Furthermore, rodents prenatally exposed to this drug display behavioral phenotypes characteristics of the human condition. Indeed, in utero exposure of rodents to VPA represents a robust model of autism exhibiting face, construct and predictive validity. This model might better represent the many cases of idiopathic autism which are of environmental/epigenetic origins than do transgenic models carrying mutations in single autism-associated genes. The VPA model provides a valuable tool to investigate the neurobiology underlying autistic behavior and to screen for novel therapeutics. Here we review the VPA-induced rodent model of autism, highlighting its importance and reliability as an environmentally-induced animal model of autism. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Maternal-fetal communication of circadian phase in a precocious rodent, the spiny mouse

    International Nuclear Information System (INIS)

    Weaver, D.R.; Reppert, S.M.

    1987-01-01

    The development of circadian rhythms was examined in a precocious rodent species, the spiny mouse. Spiny mouse pups born and reared in constant darkness expressed robust circadian rhythms in locomotor activity as early as day 5 of live. Free-running activity rhythms of pups born and reared in constant darkness were coordinated with the dam on the day of birth. Postnatal maternal influences on pup rhythmicity are minimal in this species, as pups fostered on the day of birth to dams whose circadian phases were opposite to the pups' original dams were coordinated with their original dams on the day of birth. Studies using 2-deoxy-D-[1- 14 C]-glucose authoradiography showed that there were synchronous (coordinated) rhythms in metabolic activity in the maternal and fetal suprachiasmatic nuclei, directly demonstrating prenatal coordination of maternal and fetal rhythmicity. Maternal-fetal coordination of circadian phase was not the result of direct entrainment of the fetuses to the environmental light-dark cycle. These results demonstrate that there is prenatal communication of circadian phase in this precocious species, without demonstrable postnatal maternal influences on pup circadian rhythmicity. Spiny mice therefore represent an important animal model in which circadian rhythms in the postnatal period can be used to precisely assess prenatal influences on circadian phase

  9. Phylogeny and origins of hantaviruses harbored by bats, insectivores, and rodents.

    Directory of Open Access Journals (Sweden)

    Wen-Ping Guo

    2013-02-01

    Full Text Available Hantaviruses are among the most important zoonotic pathogens of humans and the subject of heightened global attention. Despite the importance of hantaviruses for public health, there is no consensus on their evolutionary history and especially the frequency of virus-host co-divergence versus cross-species virus transmission. Documenting the extent of hantavirus biodiversity, and particularly their range of mammalian hosts, is critical to resolving this issue. Here, we describe four novel hantaviruses (Huangpi virus, Lianghe virus, Longquan virus, and Yakeshi virus sampled from bats and shrews in China, and which are distinct from other known hantaviruses. Huangpi virus was found in Pipistrellus abramus, Lianghe virus in Anourosorex squamipes, Longquan virus in Rhinolophus affinis, Rhinolophus sinicus, and Rhinolophus monoceros, and Yakeshi virus in Sorex isodon, respectively. A phylogenetic analysis of the available diversity of hantaviruses reveals the existence of four phylogroups that infect a range of mammalian hosts, as well as the occurrence of ancient reassortment events between the phylogroups. Notably, the phylogenetic histories of the viruses are not always congruent with those of their hosts, suggesting that cross-species transmission has played a major role during hantavirus evolution and at all taxonomic levels, although we also noted some evidence for virus-host co-divergence. Our phylogenetic analysis also suggests that hantaviruses might have first appeared in Chiroptera (bats or Soricomorpha (moles and shrews, before emerging in rodent species. Overall, these data indicate that bats are likely to be important natural reservoir hosts of hantaviruses.

  10. Stimulant and motivational effects of alcohol: lessons from rodent and primate models.

    Science.gov (United States)

    Brabant, Christian; Guarnieri, Douglas J; Quertemont, Etienne

    2014-07-01

    In several animal species including humans, the acute administration of low doses of alcohol increases motor activity. Different theories have postulated that alcohol-induced hyperactivity is causally related to alcoholism. Moreover, a common biological mechanism in the mesolimbic dopamine system has been proposed to mediate the stimulant and motivational effects of alcohol. Numerous studies have examined whether alcohol-induced hyperactivity is related to alcoholism using a great variety of animal models and several animal species. However, there is no review that has summarized this extensive literature. In this article, we present the various experimental models that have been used to study the relationship between the stimulant and motivational effects of alcohol in rodents and primates. Furthermore, we discuss whether the theories hypothesizing a causal link between alcohol-induced hyperactivity and alcoholism are supported by published results. The reviewed findings indicate that animal species that are stimulated by alcohol also exhibit alcohol preference. Additionally, the role of dopamine in alcohol-induced hyperactivity is well established since blocking dopaminergic activity suppresses the stimulant effects of alcohol. However, dopamine transmission plays a much more complex function in the motivational properties of alcohol and the neuronal mechanisms involved in alcohol stimulation and reward are distinct. Overall, the current review provides mixed support for theories suggesting that the stimulant effects of alcohol are related to alcoholism and highlights the importance of animal models as a way to gain insight into alcoholism. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Minimum datasets to establish a CAR-mediated mode of action for rodent liver tumors.

    Science.gov (United States)

    Peffer, Richard C; LeBaron, Matthew J; Battalora, Michael; Bomann, Werner H; Werner, Christoph; Aggarwal, Manoj; Rowe, Rocky R; Tinwell, Helen

    2018-07-01

    Methods for investigating the Mode of Action (MoA) for rodent liver tumors via constitutive androstane receptor (CAR) activation are outlined here, based on current scientific knowledge about CAR and feedback from regulatory agencies globally. The key events (i.e., CAR activation, altered gene expression, cell proliferation, altered foci and increased adenomas/carcinomas) can be demonstrated by measuring a combination of key events and associative events that are markers for the key events. For crop protection products, a primary dataset typically should include a short-term study in the species/strain that showed the tumor response at dose levels that bracket the tumorigenic and non-tumorigenic dose levels. The dataset may vary depending on the species and the test compound. As examples, Case Studies with nitrapyrin (in mice) and metofluthrin (in rats) are described. Based on qualitative differences between the species, the key events leading to tumors in mice or rats by this MoA are not operative in humans. In the future, newer approaches such as a CAR biomarker signature approach and/or in vitro CAR3 reporter assays for mouse, rat and human CAR may eventually be used to demonstrate a CAR MoA is operative, without the need for extensive additional studies in laboratory animals. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Estimation of absorbed radiation dose rates in wild rodents inhabiting a site severely contaminated by the Fukushima Dai-ichi nuclear power plant accident.

    Science.gov (United States)

    Kubota, Yoshihisa; Takahashi, Hiroyuki; Watanabe, Yoshito; Fuma, Shoichi; Kawaguchi, Isao; Aoki, Masanari; Kubota, Masahide; Furuhata, Yoshiaki; Shigemura, Yusaku; Yamada, Fumio; Ishikawa, Takahiro; Obara, Satoshi; Yoshida, Satoshi

    2015-04-01

    The dose rates of radiation absorbed by wild rodents inhabiting a site severely contaminated by the Fukushima Dai-ichi Nuclear Power Plant accident were estimated. The large Japanese field mouse (Apodemus speciosus), also called the wood mouse, was the major rodent species captured in the sampling area, although other species of rodents, such as small field mice (Apodemus argenteus) and Japanese grass voles (Microtus montebelli), were also collected. The external exposure of rodents calculated from the activity concentrations of radiocesium ((134)Cs and (137)Cs) in litter and soil samples using the ERICA (Environmental Risk from Ionizing Contaminants: Assessment and Management) tool under the assumption that radionuclides existed as the infinite plane isotropic source was almost the same as those measured directly with glass dosimeters embedded in rodent abdomens. Our findings suggest that the ERICA tool is useful for estimating external dose rates to small animals inhabiting forest floors; however, the estimated dose rates showed large standard deviations. This could be an indication of the inhomogeneous distribution of radionuclides in the sampled litter and soil. There was a 50-fold difference between minimum and maximum whole-body activity concentrations measured in rodents at the time of capture. The radionuclides retained in rodents after capture decreased exponentially over time. Regression equations indicated that the biological half-life of radiocesium after capture was 3.31 d. At the time of capture, the lowest activity concentration was measured in the lung and was approximately half of the highest concentration measured in the mixture of muscle and bone. The average internal absorbed dose rate was markedly smaller than the average external dose rate (sampling area was estimated to be approximately 52 μGy h(-1) (1.2 mGy d(-1)), even 3 years after the accident. This dose rate exceeds 0.1-1 mGy d(-1) derived consideration reference level for Reference rat

  13. Parasitic and fungal infections in synanthropic rodents in an area of urban expansion, Aracaju, Sergipe State, Brazil - doi: 10.4025/actascibiolsci.v36i1.19760

    Directory of Open Access Journals (Sweden)

    Adriana Oliveira Guimarães

    2013-09-01

    Full Text Available This study analysed the prevalence of parasitic and fungal infections in rodents in an area of urban expansion, Aracaju, Brazil. Traps were placed in the area from December 2011 to January 2013. Blood samples, faeces and hair were collected from the animals. We collected a total of 47 rodents; 44 were Rattus rattus, and 3 were Mus musculus. Parasitological evaluation revealed the cestode Hymenolepis diminuta infection in both rodent species. The nematodes Aspiculuris tetraptera and Syphacia obvelata were found in M. musculus, and the commensal Entamoeba coli was found in R. rattus. We observed that 69.2% of the R. rattus and 33.3% of the M. musculus were infected with the haemoparasite Babesia sp. The differential leukocyte count revealed normal (72.3%, neutrophilic (15.9% and lymphocytic (11.4% profiles. The evaluation showed the following species of fungi in the rodents: Aspergillus sp. (77.1%, Penicillium sp. (28.6%, Cladosporium sp. (14.3%, Mucor sp. (14.3%, Curvularia sp. (8.6%, Acremonium sp. (8.6%, Chrysosporium sp. (2.9%, Syncephalostrum sp. (2.9%, Alternaria sp. (2.9%, Trichophyton sp. (2.9% and Scopulariopsis sp. (2.9%. The parasites and fungi found in rodents are potentially zoonotic, and the presence of these household animals demonstrates their potential role as reservoirs and disseminators of fungal and parasitic infections.

  14. How Quaternary geologic and climatic events in the southeastern margin of the Tibetan Plateau influence the genetic structure of small mammals: inferences from phylogeography of two rodents, Neodon irene and Apodemus latronum.

    Science.gov (United States)

    Fan, Zhenxin; Liu, Shaoying; Liu, Yang; Zhang, Xiuyue; Yue, Bisong

    2011-03-01

    Phylogeographical studies that focus on the southeastern margin of the Tibetan Plateau are limited. The complex terrain and unique geological history make it a particularly unusual region of the Tibetan Plateau. We carried out a phylogeographical study of two rodent species Neodon irene and Apodemus latronum using the mitochondrial cytochrome b gene sequences. High genetic diversities and deep phylogenetic splits were detected in both rodents. Some haplotypes from one sampling region fell into different evolutionary clades, but most haplotypes from the same sampling regions were clustered together with each other. The results of isolation by distance analysis further substantiated that their genetic diversities were structured along geography. Thus, there were high levels of geographical structure for both rodents. Demographic analyses implied a relatively constant population size for all samples of N. irene and A. latronum in history. However, clade B of N. irene and clade 3 of A. latronum experienced population expansions at 105-32 and 156-47 Kya, respectively. Through comparison with previous studies, we suggest the high mitochondrial DNA diversities in them are probably not a species-specific feature, but a common pattern for small mammals in this unique area. Details of the historical demography of these rodents revealed in this study could provide new insights into how rodents and possibly other small mammals in this region responded to the geological and climatic events.

  15. Prevalence of Yersinia pestis in rodents and fleas associated with black-tailed prairie dogs (Cynomys ludovicianus) at Thunder Basin National Grassland, Wyoming

    Science.gov (United States)

    Thiagarajan, Bala; Bai, Ying; Gage, Kenneth L.; Cully, Jack F.

    2008-01-01

    Rodents (and their fleas) that are associated with prairie dogs are considered important for the maintenance and transmission of the bacterium (Yersinia pestis) that causes plague. Our goal was to identify rodent and flea species that were potentially involved in a plague epizootic in black-tailed prairie dogs at Thunder Basin National Grassland. We collected blood samples and ectoparasites from rodents trapped at off- and on-colony grids at Thunder Basin National Grassland between 2002 and 2004. Blood samples were tested for antibodies to Y. pestis F-1 antigen by a passive hemagglutination assay, and fleas were tested by a multiplex polymerase chain reaction, for the presence of the plague bacterium. Only one of 1,421 fleas, an Oropsylla hirsuta collected in 2002 from a deer mouse, Peromyscus maniculatus, tested positive for Y. pestis. Blood samples collected in summer 2004 from two northern grasshopper mice, Onychomys leucogaster, tested positive for Y. pestis antibodies. All three positive samples were collected from on-colony grids shortly after a plague epizootic occurred. This study confirms that plague is difficult to detect in rodents and fleas associated with prairie dog colonies, unless samples are collected immediately after a prairie dog die-off.

  16. Modelling hemoglobin and hemoglobin:haptoglobin complex clearance in a non-rodent species– pharmacokinetic and therapeutic implications

    Directory of Open Access Journals (Sweden)

    Felicitas S Boretti

    2014-10-01

    Full Text Available Preclinical studies suggest that haptoglobin (Hp supplementation could be an effective therapeutic modality during acute or chronic hemolytic diseases. Hp prevents Hb extravasation and neutralizes Hb’s oxidative and NO scavenging activity in the vasculature. Small animal models such as mouse, rat and guinea pig appear to be valuable to provide proof-of-concept for Hb neutralization by Hp in diverse pre-clinical conditions. However, these species differ significantly from human in the clearance of Hb:Hp complexes, which leads to long persistence of circulating Hb:Hp complexes after administration of human plasma derived Hp. Alternative animal models must therefore be explored to guide pre-clinical development of these potential therapeutics. In contrast to rodents, dogs have high Hp plasma concentrations comparable to human. In this study we show that like human macrophages, dog peripheral blood monocyte derived macrophages express a glucocorticoid inducible endocytic clearance pathways with a high specificity for the Hb:Hp complex. Evaluating the Beagle dog as a non-rodent model species we provide the first pharmacokinetic parameter estimates of free Hb and Hb:Hp phenotype complexes. The data reflect a drastically reduced volume of distribution (Vc of the complex compared to free Hb, increased exposures (Cmax and AUC and significantly reduced total body clearance (CL with a terminal half-life (t1/2 of approximately 12 hours. Distribution and clearance was identical for dog and human Hb (± glucocorticoid stimulation and for dimeric and multimeric Hp preparations bound to Hb. Collectively, our study supports the dog as a non-rodent animal model to study pharmacological and pharmacokinetic aspects of Hb clearance systems and apply the model to studying Hp therapeutics.

  17. Experimental Andes virus infection in deer mice: characteristics of infection and clearance in a heterologous rodent host.

    Directory of Open Access Journals (Sweden)

    Jessica R Spengler

    Full Text Available New World hantaviruses can cause hantavirus cardiopulmonary syndrome with high mortality in humans. Distinct virus species are hosted by specific rodent reservoirs, which also serve as the vectors. Although regional spillover has been documented, it is unknown whether rodent reservoirs are competent for infection by hantaviruses that are geographically separated, and known to have related, but distinct rodent reservoir hosts. We show that Andes virus (ANDV of South America, carried by the long tailed pygmy rice rat (Oligoryzomys longicaudatus, infects and replicates in vitro and in vivo in the deer mouse (Peromyscus maniculatus, the reservoir host of Sin Nombre virus (SNV, found in North America. In experimentally infected deer mice, viral RNA was detected in the blood, lung, heart and spleen, but virus was cleared by 56 days post inoculation (dpi. All of the inoculated deer mice mounted a humoral immune response by 14 dpi, and produced measurable amounts of neutralizing antibodies by 21 dpi. An up-regulation of Ccl3, Ccl4, Ccl5, and Tgfb, a strong CD4⁺ T-cell response, and down-regulation of Il17, Il21 and Il23 occurred during infection. Infection was transient with an absence of clinical signs or histopathological changes. This is the first evidence that ANDV asymptomatically infects, and is immunogenic in deer mice, a non-natural host species of ANDV. Comparing the immune response in this model to that of the immune response in the natural hosts upon infection with their co-adapted hantaviruses may help clarify the mechanisms governing persistent infection in the natural hosts of hantaviruses.

  18. Impacts of microcystin, a cyanobacterial toxin, on laboratory rodents in vivo

    Directory of Open Access Journals (Sweden)

    Andrea Ziková

    2008-01-01

    BID-BAX-BCL2 and the reactive oxygen species pathway. The reviewed data clearly show that microcystin, especially MC-LR is able to cause severe adverse impacts on laboratory rodents and therefore there is an emerging need for further research to cover the major concern about cyanobacterial water blooms affecting mammals including human beings.

  19. Trace element analysis of wild rodent tissues using the PIXE method

    International Nuclear Information System (INIS)

    Hill, M.W.; Mangelson, N.F.; Ryder, J.F.; Atwood, N.D.; Wood, B.W.

    1980-01-01

    Five species of rodents have been collected in an area near Lake Powell Utah. Common names of the five species are: Long-tailed Mouse, Small Pocket Mouse, Deer Mouse, Antelope Ground Squirrel and Kangaroo Rat. Liver, lung, kidney and hair tissues from each animal were analyzed for trace element content by proton particle-induced x-ray emission (proton PIXE) analysis. Mean concentrations for the following elements were established for the tissues of each animal type: K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb and Pb. Analyses of variance were performed on the set of elements common to all tissues. Some significant differences in element concentrations were found between animal species and between tissue types. These differences lead to the following orders based on element concentration: Long-tailed Mouse greater than or equal to Antelope Ground Squirrel greater than or equal to Kangaroo Rat greater than or equal to Small Pocket Mouse and liver greater than or equal to kidney greater than or equal to lung greater than or equal to hair. Linear regression analyses were also performed on mean elemental concentrations in tissues. These analyses lead to several conclusions. First, the pattern of trace element concentrations in each of the four tissues is the same in all five species. Second, the pattern of trace element concentrations is the same in all four tissues of one species with the exception of Ti and Fe in hair. Third, the variation of an element in the hair cannot predict the variation of that same element in the other three tissues. Only K, Ca, Ti, Mn, Fe, Cu, and Zn were included in the third study

  20. The developmental dynamics of behavioral growth processes in rodent egocentric and allocentric space.

    Science.gov (United States)

    Golani, Ilan

    2012-06-01

    In this review I focus on how three methodological principles advocated by Philip Teitelbaum influenced my work to this day: that similar principles of organization should be looked for in ontogeny and recovery of function; that the order of emergence of behavioral components provides a view on the organization of that behavior; and that the components of behavior should be exhibited by the animal itself in relatively pure form. I start by showing how these principles influenced our common work on the developmental dynamics of rodent egocentric space, and then proceed to describe how these principles affected my work with Yoav Benjamini and others on the developmental dynamics of rodent allocentric space. We analyze issues traditionally addressed by physiological psychologists with methods borrowed from ethology, EW (Eshkol-Wachman) movement notation, dynamical systems and exploratory data analysis. Then we show how the natural origins of axes embodied by the behavior of the organism itself, are used by us as the origins of axes for the measurement of the developmental moment-by-moment dynamics of behavior. Using this methodology we expose similar principles of organization across situations, species and preparations, provide a developmental view on the organization of behavior, expose the natural components of behavior in relatively pure form, and reveal how low level primitives generate higher level constructs. Advances in tracking technology should allow us to study how movements in egocentric and allocentric spaces interlace. Tracking of multi-limb coordination, progress in online recording of neural activity in freely moving animals, and the unprecedented accumulation of genetically engineered mouse preparations makes the behavioral ground plan exposed in this review essential for a systematic study of the brain/behavior interface. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Seroprevalence of Angiostrongylus cantonensis in wild rodents from the Canary Islands.

    Science.gov (United States)

    Martin-Alonso, Aarón; Foronda, Pilar; Quispe-Ricalde, María Antonieta; Feliu, Carlos; Valladares, Basilio

    2011-01-01

    Angiostrongylus cantonensis is a lungworm of rats (Muridae) that is the causative agent of human cerebral angiostrongyliasis. The life cycle of A. cantonensis involves rats and mollusks as the definitive and intermediate hosts, respectively. This study was designed to increase the knowledge about the occurrence and distribution of A. cantonensis in its definitive host in the Canary Islands, using parasitological and serological analysis in different areas and age groups. Between 2009 and 2010, 54 black rats (Rattus rattus) from Tenerife were captured from six human-inhabited areas and sera samples were obtained. The lung nematodes were identified by morphological and molecular tools as A. cantonensis. The 31-kDa glycoprotein antigen was purified from A. cantonensis adult worms by electrophoresis and electroelution. Of the 54 tested rodents, 30 showed IgG antibodies against A. cantonensis 31-kDa antigen by ELISA. Therefore, the overall seroprevalence was 55.6% (95% CI: 42.4-68). Seroprevalent rodents were found in all the 6 areas. This 31-kDa antigen was not recognized by some sera of rats infected by other helminth species (but not A. cantonensis). Seroprevalence of IgG antibodies against A. cantonensis and prevalence based on the presence of adult worms showed significant correlation (R(2) = 0.954, p<0.05). The present results could indicate a high prevalence of A. cantonensis in Tenerife and suggest the inclusion of two new zones in the distribution area of the parasite. The commonness and wide distribution of A. cantonensis in rats implies the presence of intermediate hosts, indicating that humans may be at risk of getting infected.

  2. Dim nighttime light impairs cognition and provokes depressive-like responses in a diurnal rodent.

    Science.gov (United States)

    Fonken, Laura K; Kitsmiller, Emily; Smale, Laura; Nelson, Randy J

    2012-08-01

    Circadian disruption is a common by-product of modern life. Although jet lag and shift work are well-documented challenges to circadian organization, many more subtle environmental changes cause circadian disruption. For example, frequent fluctuations in the timing of the sleep/wake schedule, as well as exposure to nighttime lighting, likely affect the circadian system. Most studies of these effects have focused on nocturnal rodents, which are very different from diurnal species with respect to their patterns of light exposure and the effects that light can have on their activity. Thus, the authors investigated the effect of nighttime light on behavior and the brain of a diurnal rodent, the Nile grass rat. Following 3 weeks of exposure to standard light/dark (LD; 14:10 light [~150 lux] /dark [0 lux]) or dim light at night (dLAN; 14:10 light [~150 lux] /dim [5 lux]), rats underwent behavioral testing, and hippocampal neurons within CA1, CA3, and the dentate gyrus (DG) were examined. Three behavioral effects of dLAN were observed: (1) decreased preference for a sucrose solution, (2) increased latency to float in a forced swim test, and (3) impaired learning and memory in the Barnes maze. Light at night also reduced dendritic length in DG and basilar CA1 dendrites. Dendritic length in the DG positively correlated with sucrose consumption in the sucrose anhedonia task. Nighttime light exposure did not disrupt the pattern of circadian locomotor activity, and all grass rats maintained a diurnal activity pattern. Together, these data suggest that exposure to dLAN can alter affective responses and impair cognition in a diurnal animal.

  3. Effect of woodland patch size on rodent seed predation in a fragmented landscape

    Directory of Open Access Journals (Sweden)

    J. Loman

    2007-05-01

    Full Text Available Predation on large woody plant seeds; chestnuts, acorns and sloe kernels, was studied in deciduous forests of two size classes: small woodlots (<1 ha and large woods (at least 25 ha in southern Sweden. Seeds used for the study were artificially distributed on the forest ground and seed predation measured as seed removal. Predation rate was similar in both types of woods. However, rodent density was higher in small woodlots and a correction for differences in rodent density showed that predation rate per individual rodent was higher in the large woods. This suggests that the small woodlots (including the border zone and their adjacent fields have more rodent food per area unit. A small woodlot cannot be considered a representative sample of a large continuous forest, even if the habitats appear similar. There was a strong effect of rodent density on seed predation rate. This suggests that rodents are major seed predators in this habitat.

  4. Distribution and protection of endemic or threatened rodents ...

    African Journals Online (AJOL)

    Species richness of the target species is highest in the south-western parts of the country, and hotspots of endemism coincide with those of species richness. However, Red Data Book species hotspots are confined to the north-eastern parts of the country. One species richness hotspol in the Succulent Karoo contains no ...

  5. Validating activity indices from camera traps for commensal rodents and other wildlife in and around farm buildings.

    Science.gov (United States)

    Lambert, Mark; Bellamy, Fiona; Budgey, Richard; Callaby, Rebecca; Coats, Julia; Talling, Janet

    2018-01-01

    Indices of rodent activity are used as indicators of population change during field evaluation of rodenticides. We investigated the potential for using camera traps to determine activity indices for commensal rodents living in and around farm buildings, and sought to compare these indices against previously calibrated survey methods. We recorded 41 263 images of 23 species, including Norway rats (Rattus norvegicus Berk.) and house mice (Mus musculus L.). We found a positive correlation between activity indices from camera traps and activity indices from a method (footprint tracking) previously shown to have a linear relationship with population size for Norway rats. Filtering the camera trap data to simulate a 30-s delay between camera trigger events removed 59.9% of data and did not adversely affect the correlation between activity indices from camera traps and footprint tracking. The relationship between activity indices from footprint tracking and Norway rat population size is known from a previous study; from this, we determined the relationship between activity indices from camera traps and population size for Norway rats living in and around farm buildings. Systematic use of camera traps was used to determine activity indices for Norway rats living in and around farm buildings; the activity indices were positively correlated with those derived from a method previously calibrated against known population size for this species in this context. © 2017 Crown copyright. Pest Management Science © 2017 Society of Chemical Industry. © 2017 Crown copyright. Pest Management Science © 2017 Society of Chemical Industry.

  6. Ecology of rodent-associated hantaviruses in the Southern Cone of South America: Argentina, Chile, Paraguay, and Uruguay.

    Science.gov (United States)

    Palma, R Eduardo; Polop, Jaime J; Owen, Robert D; Mills, James N

    2012-04-01

    Thirteen hantavirus genotypes, associated with at least 12 sigmodontine reservoir rodents, have been recognized in the four countries that represent the Southern Cone of South America. Host-virus relationships are not as well defined as in North America; several Southern Cone hantaviruses appear to share a common host and some viruses do not occur throughout the range of their host. Although hantavirus-host relationships in the Southern Cone are less strictly concordant with the single-host-single-virus pattern reported elsewhere, recent studies suggest that much of the ambiguity may result from an incomplete understanding of host and hantavirus systematics. Although some Southern Cone host species are habitat generalists, some sympatric species are habitat specialists, helping to explain how some strict host-virus pairings may be maintained. In some cases, host population densities were higher in peridomestic habitats and prevalence of hantavirus infection was higher in host populations in peridomestic habitats. Seasonal and multiyear patterns in climate and human disturbance affect host population densities, prevalence of infection, and disease risk to humans. Unusually high hantavirus antibody prevalence in indigenous human populations may be associated with frequent and close contact with host rodents. Ongoing studies are improving our understanding of hantavirus-host ecology and providing tools that may predict human risk.

  7. Ecological Risk Assessment of Perchlorate in Avian Species, Rodents, Amphibians and Fish: FY2003

    Science.gov (United States)

    2005-10-01

    Ecological Receptors at the Longhorn Army Ammunition Plant (LHAAP), Karnack, TX. Ecotoxicology , 10: 305-313. Smith JN, Pan X, Gentles, BA, Smith...Page 32 of 225 Hayes, TB. 2000. Endocrine disruption in amphibians. In Sparling DW, Linder G, Bishop C, eds. Ecotoxicology of Amphibians and... macrophytes and was programmed in Matlab using difference equations. To simulate and predict the uptake and transport of explosives in various

  8. Ecological Risk Assessment of Perchlorate in Avian Species, Rodents, Amphibians and Fish

    Science.gov (United States)

    2003-04-01

    http://www .indiana.edu/- axolotl ). 10.0 JUSTIFICATION OF TEST SYSTEM Perchlorate occurs in ground and surface waters in 44 states in the USA... axolotl ). * Sequentially numbered in order of the date that the change is effective Dept. of Biological Sciences (DBS) Box 43131 Lubbock, TX 79409...KCl, 0.025 giL; CaCh2 H20, 0.65 g/L; MgS04·7H20, 0.1 giL (http://www.indiana.edu/~ axolotl ). *Sequentially numbered in order of the date that the

  9. Differential resistance to cell entry by porcine endogenous retrovirus subgroup A in rodent species

    Czech Academy of Sciences Publication Activity Database

    Mattiuzzo, G.; Matoušková, Magda; Takeuchi, Y.

    2007-01-01

    Roč. 14, č. 4 (2007), s. 93-93 ISSN 1742-4690 Grant - others:EC(XE) LSHB-CT-2006-037377 Institutional research plan: CEZ:AV0Z50520514 Keywords : PERV * xenotransplantation * receptor Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.040, year: 2007

  10. Ecological Risk Assessment of Perchlorate in Avian Species, Rodents, Amphibians and Fish

    Science.gov (United States)

    2008-08-01

    nutritional physiology. Vet. Res. Commun. 8:77–91. Lee S-Y, Brodman BW. 2004. Biodegradation of 1,3,5-trinitro-1,3,5-triazine (RDX). Journal of...laevis (African clawed frog) Strain: Outbred Age: embryo/Larvae/Adults Source: All of Xenopus used in this proposal were bred from captive stocks...Laboratory studies have shown that PAHs may stimulate the induction of hepatic monooxygenase activity in birds , although PAHs are rapidly metabolized, and

  11. LINE-1 distribution in six rodent genomes follow a species-specific ...

    Indian Academy of Sciences (India)

    Muridae .... 2006; Song and Boissinot 2007) and in gene-poor regions ... tions were: 10 min at 94◦C, followed by 30 cycles of 45 s ... 70% formamide/2 × SSC for 1 min at 72◦C. Each of the L1 ... The percentage of similarity between the sequences.

  12. Helminth Infections of Rodents and Their Zoonotic Importance in Boyer-Ahmad District, Southwestern Iran

    OpenAIRE

    RANJBAR, Mohammad Javad; SARKARI, Bahador; MOWLAVI, Gholam Reza; SEIFOLLAHI, Zeinab; MOSHFE, Abdolali; ABDOLAHI KHABISI, Samaneh; MOBEDI, Iraj

    2017-01-01

    AbstractBackground: Rodents are considered as reservoirs of various zoonotic diseases including helminthic infections. The current study aimed to evaluate the prevalence of helminth infections in rodents, in Boyer-Ahmad district, Southwestern Iran.Methods: Overall, 52 rodents were captured from various areas of the district by Sherman live traps. The animals were then euthanized and dissected. During necropsy, each organ was examined macroscopically for presence of any cyst or visible parasit...

  13. Tularemia and plague survey in rodents in an earthquake zone in southeastern Iran

    Science.gov (United States)

    Gyuranecz, Miklós

    2015-01-01

    OBJECTIVES: Earthquakes are one the most common natural disasters that lead to increased mortality and morbidity from transmissible diseases, partially because the rodents displaced by an earthquake can lead to an increased rate of disease transmission. The aim of this study was to evaluate the prevalence of plague and tularemia in rodents in the earthquake zones in southeastern Iran. METHODS: In April 2013, a research team was dispatched to explore the possible presence of diseases in rodents displaced by a recent earthquake magnitude 7.7 around the cities of Khash and Saravan in Sistan and Baluchestan Province. Rodents were trapped near and in the earthquake zone, in a location where an outbreak of tularemia was reported in 2007. Rodent serums were tested for a serological survey using an enzyme-linked immunosorbent assay. RESULTS: In the 13 areas that were studied, nine rodents were caught over a total of 200 trap-days. Forty-eight fleas and 10 ticks were obtained from the rodents. The ticks were from the Hyalomma genus and the fleas were from the Xenopsylla genus. All the trapped rodents were Tatera indica. Serological results were negative for plague, but the serum agglutination test was positive for tularemia in one of the rodents. Tatera indica has never been previously documented to be involved in the transmission of tularemia. CONCLUSIONS: No evidence of the plague cycle was found in the rodents of the area, but evidence was found of tularemia infection in rodents, as demonstrated by a positive serological test for tularemia in one rodent. PMID:26602769

  14. [11 C]Rhodamine-123: Synthesis and biodistribution in rodents

    International Nuclear Information System (INIS)

    Bao Xiaofeng; Lu Shuiyu; Liow, Jeih-San; Morse, Cheryl L.; Anderson, Kacey B.; Zoghbi, Sami S.; Innis, Robert B.; Pike, Victor W.

    2012-01-01

    Introduction: Rhodamine-123 is a known substrate for the efflux transporter, P-glycoprotein (P-gp). We wished to assess whether rhodamine-123 might serve as a useful substrate for developing probes for imaging efflux transporters in vivo with positron emission tomography (PET). For this purpose, we aimed to label rhodamine-123 with carbon-11 (t 1/2 = 20.4 min) and to study its biodistribution in rodents. Methods: [ 11 C]Rhodamine-123 was prepared by treating rhodamine-110 (desmethyl-rhodamine-123) with [ 11 C]methyl iodide. The biodistribution of this radiotracer was studied with PET in wild-type mice and rats, in efflux transporter knockout mice, in wild-type rats pretreated with DCPQ (an inhibitor of P-gp) or with cimetidine (an inhibitor of organic cation transporters; OCT), and in P-gp knockout mice pretreated with cimetidine. Unchanged radiotracer in forebrain, plasma and peripheral tissues was also measured ex vivo at 30 min after radiotracer administration to wild-type and efflux transporter knockout rodents. Results: [ 11 C]Rhodamine-123 was obtained in 4.4% decay-corrected radiochemical yield from cyclotron-produced [ 11 C]carbon dioxide. After intravenous administration of [ 11 C]rhodamine-123 to wild-type rodents, PET and ex vivo measurements showed radioactivity uptake was very low in brain, but relatively high in some other organs such as heart, and especially liver and kidney. Inhibition of P-gp increased uptake in brain, heart, kidney and liver, but only by up to twofold. Secretion of radioactivity from kidney was markedly reduced by OCT knockout or pretreatment with cimetidine. Conclusions: [ 11 C]Rhodamine-123 was unpromising as a PET probe for P-gp function and appears to be a strong substrate of OCT in kidney. Cimetidine appears effective for blocking OCT in kidney in vivo.

  15. Sex differences in chronic stress effects on cognition in rodents.

    Science.gov (United States)

    Luine, Victoria; Gomez, Juan; Beck, Kevin; Bowman, Rachel

    2017-01-01

    Chronic stress causes deleterious changes in physiological function in systems ranging from neural cells in culture to laboratory rodents, sub-human primates and humans. It is notable, however, that the vast majority of research in this area has been conducted in males. In this review, we provide information about chronic stress effects on cognition in female rodents and contrast it with responses in male rodents. In general, females show cognitive resilience to chronic stressors which impair male cognitive function using spatial tasks including the radial arm maze, radial arm water maze, Morris water maze, Y-maze and object placement. Moreover, stress often enhances female performance in some of these cognitive tasks. Memory in females is not affected by stress in non-spatial memory tasks like recognition memory and temporal order recognition memory while males show impaired memory following stress. We discuss possible bases for these sex-dependent differences including the use of different strategies by the sexes to solve cognitive tasks. Whether the sex differences result from changes in non-mnemonic factors is also considered. Sex-dependent differences in alcohol and drug influences on stress responses are also described. Finally, the role of neurally derived estradiol in driving sex differences and providing resilience to stress in females is shown. The importance of determining the nature and extent of sex differences in stress responses is that such differences may provide vital information for understanding why some stress related diseases have different incidence rates between the sexes and for developing novel therapeutic treatments. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Rodent models of congenital and hereditary cataract in man.

    Science.gov (United States)

    Tripathi, B J; Tripathi, R C; Borisuth, N S; Dhaliwal, R; Dhaliwal, D

    1991-01-01

    Because the organogenesis and physiology of the lens are essentially similar in various mammals, an understanding of the etiology and pathogenesis of the formation of cataract in an animal model will enhance our knowledge of cataractogenesis in man. In this review, we summarize the background, etiology, and pathogenesis of cataracts that occur in rodents. The main advantages of using rodent mutants include the well-researched genetics of the animals and the comparative ease of breeding of large litters. Numerous rodent models of congenital and hereditary cataracts have been studied extensively. In mice, the models include the Cts strain, Fraser mouse, lens opacity gene (Lop) strain, Lop-2 and Lop-3 strains, Philly mouse, Nakano mouse, Nop strain, Deer mouse, Emory mouse, Swiss Webster strain, Balb/c-nct/nct mouse, and SAM-R/3 strain. The rat models include BUdR, ICR, Sprague-Dawley, and Wistar rats, the spontaneously hypertensive rat (SHR), the John Rapp inbred strain of Dahl salt-sensitive rat, as well as WBN/Kob, Royal College of Surgeons (RCS), and Brown-Norway rats. Other proposed models for the study of hereditary cataract include the degu and the guinea pig. Because of the ease of making clinical observations in vivo and the subsequent availability of the intact lens for laboratory analyses at different stages of cataract formation, these animals provide excellent models for clinicopathologic correlations, for monitoring of the natural history of the aging process and of metabolic defects, as well as for investigations on the effect of cataract-modulating agents and drugs, including the prospect of gene therapy.

  17. Ghrelin influences novelty seeking behavior in rodents and men.

    Science.gov (United States)

    Hansson, Caroline; Shirazi, Rozita H; Näslund, Jakob; Vogel, Heike; Neuber, Corinna; Holm, Göran; Anckarsäter, Henrik; Dickson, Suzanne L; Eriksson, Elias; Skibicka, Karolina P

    2012-01-01

    Recent discoveries indicate an important role for ghrelin in drug and alcohol reward and an ability of ghrelin to regulate mesolimbic dopamine activity. The role of dopamine in novelty seeking, and the association between this trait and drug and alcohol abuse, led us to hypothesize that ghrelin may influence novelty seeking behavior. To test this possibility we applied several complementary rodent models of novelty seeking behavior, i.e. inescapable novelty-induced locomotor activity (NILA), novelty-induced place preference and novel object exploration, in rats subjected to acute ghrelin receptor (growth hormone secretagogue receptor; GHSR) stimulation or blockade. Furthermore we assessed the possible association between polymorphisms in the genes encoding ghrelin and GHSR and novelty seeking behavior in humans. The rodent studies indicate an important role for ghrelin in a wide range of novelty seeking behaviors. Ghrelin-injected rats exhibited a higher preference for a novel environment and increased novel object exploration. Conversely, those with GHSR blockade drastically reduced their preference for a novel environment and displayed decreased NILA. Importantly, the mesolimbic ventral tegmental area selective GHSR blockade was sufficient to reduce the NILA response indicating that the mesolimbic GHSRs might play an important role in the observed novelty responses. Moreover, in untreated animals, a striking positive correlation between NILA and sucrose reward behavior was detected. Two GHSR single nucleotide polymorphisms (SNPs), rs2948694 and rs495225, were significantly associated with the personality trait novelty seeking, as assessed using the Temperament and Character Inventory (TCI), in human subjects. This study provides the first evidence for a role of ghrelin in novelty seeking behavior in animals and humans, and also points to an association between food reward and novelty seeking in rodents.

  18. The beneficial role of Naringin- a citrus bioflavonoid, against oxidative stress-induced neurobehavioral disorders and cognitive dysfunction in rodents: A systematic review and meta-analysis.

    Science.gov (United States)

    Viswanatha, Gollapalle Lakshminarayanashastry; Shylaja, H; Moolemath, Yogananda

    2017-10-01

    Naringin is a bioflavonoid, very abundantly found in citrus species. In literature, naringin has been scientifically well documented for its beneficial effects in various neurological disorders. In this systematic review and meta-analysis, we have made an attempt to correlate the protective role of naringin against oxidative stress-induced neurological disorders in rodents. The systematic search was performed using electronic databases; the search was mainly focused on the role of naringin in oxidative stress-induced neuropathological conditions in rodents. While, the meta-analysis was performed on the effect of naringin on oxidative stress markers [superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), reduced glutathione (GSH), lipid peroxidation (LPO)], nitrite, mitochondrial complexes (I to IV) and enzymes (acetylcholinesterase, Na + -K + -ATPase, Ca 2+ -ATPase, and Mg 2+ -ATPase) in the rodent brain. The data was analyzed using Review Manager Software. Based on the inclusion and exclusion criteria, twenty studies were selected. The meta-analysis revealed that, naringin could significantly inhibit various physical and chemical stimuli- induced neurological perturbances in the rodent brain, mediated through oxidative stress. Further, naringin also significantly restored the levels of all the oxidative stress markers (oxidative, nitrosative, enzymes, and mitochondrial complexes) in different parts of the rodent brain. This systematic review and meta-analysis supports the available scientific evidence on the beneficial role of naringin in the management of various neurological ailments. However, further studies involving human subjects is recommended to establish the safety and therapeutic efficacy in humans. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Rodent Habitat On ISS: Spaceflight Effects On Mouse Behavior

    Science.gov (United States)

    Ronca, A. E.; Moyer, E. L.; Talyansky, Y.; Padmanabhan, S.; Choi, S.; Gong, C.; Globus, R. K.

    2016-01-01

    The NASA Decadal Survey (2011), Recapturing a Future for Space Exploration: Life and Physical Sciences Research for a New Era, emphasized the importance of expanding NASA life sciences research to long duration, rodent experiments on the International Space Station (ISS). To accomplish this objective, flight hardware, operations, and science capabilities supporting mouse studies in space were developed at NASA Ames Research Center. The first flight experiment carrying mice, Rodent Research Hardware and Operations Validation (Rodent Research-1), was launched on Sept 21, 2014 in an unmanned Dragon Capsule, SpaceX4, exposing the mice to a total of 37 days in space. Ground control groups were maintained in environmental chambers at Kennedy Space Center. Mouse health and behavior were monitored for the duration of the experiment via video streaming. Here we present behavioral analysis of two groups of five C57BL/6 female adult mice viewed via fixed camera views compared with identically housed Ground Controls. Flight (Flt) and Ground Control (GC) mice exhibited the same range of behaviors, including eating, drinking, exploratory behavior, self- and allo-grooming, and social interactions at similar or greater levels of occurrence. Mice propelled themselves freely and actively throughout the Habitat using their forelimbs to push off or by floating from one cage area to another, and they quickly learned to anchor themselves using tails and/or paws. Overall activity was greater in Flt as compared to GC mice, with spontaneous ambulatory behavior including the development of organized ‘circling’ or ‘race-tracking’ behavior that emerged within the first few days of flight and encompassed the primary dark cycle activity for the remainder of the experiment. We quantified the bout frequency, duration and rate of circling with respect to characteristic behaviors observed in the varying stages of the progressive development of circling: flipping utilizing two sides of the

  20. Polycystic echinococcosis in Colombia: the larval cestodes in infected rodents.

    Science.gov (United States)

    Morales, G A; Guzman, V H; Wells, E A; Angel, D

    1979-07-01

    Described are the characteristics of the polycystic larval cestodes found in an endemic area of echinococcosis in the Easter Plains of Colombia and the tissue reaction evoked in infected rodents. Of 848 free-ranging animals examined, polycystic hydatids were found in 44/93 Cuniculus paca and 1/369 Proechimys sp. None of 20 Dasyprocta fuliginosa examined was infected, but hunters provided a heart with hydatid cysts and information about two additional animals with infected livers. Recognition of an endemic area of polycystic echinococcosis provides a means to investigate the life cycle of the parasites and to study the histogenesis of the larval cestodes in susceptible laboratory animals.

  1. Models and detection of spontaneous recurrent seizures in laboratory rodents

    Directory of Open Access Journals (Sweden)

    Bin Gu

    2017-07-01

    Full Text Available Epilepsy, characterized by spontaneous recurrent seizures (SRS, is a serious and common neurological disorder afflicting an estimated 1% of the population worldwide. Animal experiments, especially those utilizing small laboratory rodents, remain essential to understanding the fundamental mechanisms underlying epilepsy and to prevent, diagnose, and treat this disease. While much attention has been focused on epileptogenesis in animal models of epilepsy, there is little discussion on SRS, the hallmark of epilepsy. This is in part due to the technical difficulties of rigorous SRS detection. In this review, we comprehensively summarize both genetic and acquired models of SRS and discuss the methodology used to monitor and detect SRS in mice and rats.

  2. Do farming practices influence population dynamics of rodents?

    DEFF Research Database (Denmark)

    Massawe, A W; Rwamugira, W; Leirs, Herwig

    2007-01-01

    A capture-mark-recapture study was conducted in crop fields in Morogoro, Tanzania, to investigate how the population dynamics of multimammate field rats, Mastomys natalensis, was influenced by the commonly practised land preparation methods and cropping systems. Two land preparation methods (trac...... practices. In maize fields in Tanzania, the crop is most susceptible to damage by M. natalensis in the first 2 weeks after planting, and therefore, lower densities of rodents will result into lower crop damage in tractor ploughed fields....

  3. The water economy of South American desert rodents: from integrative to molecular physiological ecology.

    Science.gov (United States)

    Bozinovic, Francisco; Gallardo, Pedro

    2006-01-01

    Rodents from arid and semi-arid habitats live under conditions where the spatial and temporal availability of free water is limited, or scarce, thus forcing these rodents to deal with the problem of water conservation. The response of rodents to unproductive desert environments and water deficits has been intensively investigated in many deserts of the world. However, current understanding of the cellular, systemic and organismal physiology of water economy relies heavily on short-term, laboratory-oriented experiments, which usually focus on responses at isolated levels of biological organization. In addition, studies in small South American mammals are scarce. Indeed xeric habitats have existed in South America for a long time and it is intriguing why present day South American desert rodents do not show the wide array of adaptive traits to desert life observed for rodents on other continents. Several authors have pointed out that South American desert rodents lack physiological and energetic specialization for energy and water conservation, hypothesizing that their success is based more on behavioral and ecological strategies. We review phenotypic flexibility and physiological diversity in water flux rate, urine osmolality, and expression of water channels in South American desert-dwelling rodents. As far as we know, this is the first review of integrative studies at cellular, systemic and organismal levels. Our main conclusion is that South American desert rodents possess structural as well as physiological systems for water conservation, which are as remarkable as those found in "classical" rodents inhabiting other desert areas of the world.

  4. The role of rodents in avian influenza outbreaks in poultry farms: a review.

    Science.gov (United States)

    Velkers, Francisca C; Blokhuis, Simon J; Veldhuis Kroeze, Edwin J B; Burt, Sara A

    2017-12-01

    Wild migratory birds are associated with global avian influenza virus (AIV) spread. Although direct contact with wild birds and contaminated fomites is unlikely in modern non-free range poultry farms applying biosecurity measures, AIV outbreaks still occur. This suggests involvement of other intermediate factors for virus transmission between wild birds and poultry. This review describes current evidence of the potential role of rodents in AIV transmission from wild birds to poultry and between poultry houses. Rodents can be abundant around poultry houses, share their habitat with waterfowl and can readily enter poultry houses. Survival of AIV from waterfowl in poultry house surroundings and on the coat of rodents suggests that rodents are likely to act as mechanical vector. AIVs can replicate in rodents without adaptation, resulting in high viral titres in lungs and nasal turbinates, virus presence in nasal washes and saliva, and transmission to naïve contact animals. Therefore, active AIV shedding by infected rodents may play a role in transmission to poultry. Further field and experimental studies are needed to provide evidence for a role of rodents in AIV epidemiology. Making poultry houses rodent-proof and the immediate surroundings unattractive for rodents are recommended as preventive measures against possible AIV introduction.

  5. Multiple Co-infections of Rodents with Hantaviruses, Leptospira, and Babesia in Croatia

    Science.gov (United States)

    Turk, Nenad; Korva, Miša; Margaletić, Josip; Beck, Relja; Vucelja, Marko; Habuš, Josipa; Svoboda, Petra; Županc, Tatjana Avšič; Henttonen, Heikki; Markotić, Alemka

    2012-01-01

    Abstract Hantaviruses, Leptospira spp., and Babesia spp. are rodent-borne pathogens present worldwide. We studied multiple co-infections of small rodents in Croatia with all three pathogens. Twenty-eight Apodemus flavicollis and 16 Myodes glareolus were tested for the presence of hantavirus RNA by real-time RT-PCR, Leptospira strains by renoculture method and Babesia DNA by PCR. Anti-hantavirus antibodies and anti-Leptospira antibodies were detected by serological methods. Very high infection rates with each pathogen were found in A. flavicollis: 20 of 28 rodents (71%) were infected with Dobrava virus, 13 rodents (46%) were infected with Leptospira, and 5 rodents (18%) were infected with Babesia. Multiple co-infections with all three pathogens were found in 3 of 28 (11%) A. flavicollis animals, suggesting that the same rodent host can be infected with several pathogens at the same time. Dual infections with both hantaviruses and Leptospira were found in 7 of 44 rodents (16%), with hantaviruses and Babesia in 2 rodents (5%), and double infection with both Leptospira and Babesia were found in 1 rodent (2%). Since hantaviruses, Leptospira, and Babesia have similar geographical distributions, it is to be expected that in other parts of the world multiple co-infections, representing a serious threat to public health, can be found. PMID:22217170

  6. Specific diversity and morphological indices of muriform rodents in some areas of Semipalatinsk test range zone

    International Nuclear Information System (INIS)

    Magda, I.N.; Chernykh, A.B.; Morozov, A.E.; Bushneva, I.A.; Ponyavkina, A.G.

    2002-01-01

    There were presented the results of the preliminary estimation of comparative specific diversity and morphological indices of muriform rodents inhabiting separate areas of the Semipalatinsk test site. (author)

  7. Molecular identification of hard ticks (Ixodes sp.) infesting rodents in Selangor, Malaysia

    Science.gov (United States)

    Ishak, Siti Nabilah; Shiang, Lim Fang; Taib, Farah Shafawati Mohd; Jing, Khoo Jing; Nor, Shukor Md; Yusof, Muhammad Afif; Sah, Shahrul Anuar Mohd; Sitam, Frankie Thomas; Japning, Jeffrine Rovie Ryan

    2018-04-01

    This study aims to identify hard ticks (Ixodes sp.) infesting rodents in three different sites in Selangor, Malaysia using a molecular approach. A total of 11 individual ticks infesting four different host species (Rattus tiomanicus, Rattus ratus, Maxomys surifer and Sundamys muelleri) were examined based on its morphological features, followed by molecular identification using mitochondrial 16S rDNA gene. Confirmation of the species identity was accomplished by using BLAST program. Clustering analysis based on 16S rDNA sequences was carried out by constructing Neighbour-joining (NJ) and Maximum parsimony (MP) tree using MEGA 7 to clarify the genetic identity of Ixodes sp. Based on morphological features, all individual ticks were only able to be identified up to genus level as most of the samples were fully engorged, damaged and lacked morphological characters. However, molecular analysis of samples revealed 99% similarity with Ixodes granulatus from the GenBank database. Thus, the result of this study showed that all these ticks (Ixodes granulatus) were genetically affiliated to a monophyletic group with highly homogenous sequences.

  8. Endo-parasite fauna of rodents caught in five wet markets in Kuala Lumpur and its potential zoonotic implications.

    Science.gov (United States)

    Paramasvaran, S; Sani, R A; Hassan, L; Hanjeet, K; Krishnasamy, M; John, J; Santhana, R; Sumarni, M G; Lim, K H

    2009-04-01

    Rodents were collected from five wet markets (Chow Kit, Dato Keramat, Setapak, Jinjang and Kepong) in Kuala Lumpur, Federal Territory between March to April 2006. Ninety seven rats were trapped using wire traps measuring 29 x 22 x 50 cm baited with fruits, coconuts, dried fish or sweet potatoes. A total of 17 different species of parasites were identified from three species of rats out of which 11 (65%) were identified to be zoonotic. The helminths identified from the urban rats were nematodes- Capillaria hepatica, Gongylonema neoplasticum, Heterakis spumosa, Heterakis sp., Masterphorus muris, Nippostrongylus brasiliensis, Physolaptera sp., Pterogodermatis sp., Rictularia tani and Syphacia muris; cestodes- Hymenolepis nana, Hymenolepis diminuta, Hymenolepis sabnema, Hymenolepis sp., Raillietina sp. and Taenia taeniaeformis, and acanthocephalan- Moniliformis moniliformis. The following parasites are of potential medical importance: C. hepatica, G. neoplasticum, R. tani, S. muris, H. diminuta, H. nana, Raillietina sp. and T. taeniaeformis.

  9. Risk Prioritization Tool to Identify the Public Health Risks of Wildlife Trade: The Case of Rodents from Latin America.

    Science.gov (United States)

    Bueno, I; Smith, K M; Sampedro, F; Machalaba, C C; Karesh, W B; Travis, D A

    2016-06-01

    Wildlife trade (both formal and informal) is a potential driver of disease introduction and emergence. Legislative proposals aim to prevent these risks by banning wildlife imports, and creating 'white lists' of species that are cleared for importation. These approaches pose economic harm to the pet industry, and place substantial burden on importers and/or federal agencies to provide proof of low risk for importation of individual species. As a feasibility study, a risk prioritization tool was developed to rank the pathogens found in rodent species imported from Latin America into the United States with the highest risk of zoonotic consequence in the United States. Four formally traded species and 16 zoonotic pathogens were identified. Risk scores were based on the likelihood of pathogen release and human exposure, and the severity of the disease (consequences). Based on the methodology applied, three pathogens (Mycobacterium microti, Giardia spp. and Francisella tularensis) in one species (Cavia porcellus) were ranked as highest concern. The goal of this study was to present a methodological approach by which preliminary management resources can be allocated to the identified high-concern pathogen-species combinations when warranted. This tool can be expanded to other taxa and geographic locations to inform policy surrounding the wildlife trade. © 2015 Blackwell Verlag GmbH.

  10. Paleoparasitological finding of eggs of nematodes in rodent coprolites dated at the early Holocene from the archaeological site Cerro Casa de Piedra 7, Santa Cruz, Argentina.

    Science.gov (United States)

    Sardella, N H; Fugassa, M H

    2011-12-01

    The aim of the present study was to examine the parasite remains present in rodent coprolites collected from the archaeological site Cerro Casa de Piedra 7 (CCP7), located in the Perito Moreno National Park (47°57'S, 72°05'W), Santa Cruz Province, Argentina. Eight coprolites obtained from the layer 17, dated at 10,620 ± 40 to 9,390 ± 40 yr B.P., were examined for parasites. Feces were processed whole, rehydrated, homogenized, subjected to spontaneous sedimentation, and examined via light microscopy. Eggs of parasites were measured and photographed. Seven of 8 coprolites possessed 199 eggs of 2, probably new, species of nematodes, including 43 eggs of Heteroxynema sp. Hall, 1916 (Cavioxyura sp. Quentin, 1975) (Oxyurida, Heteroxynematidae), and 156 eggs of Trichuris sp. Roederer, 1761 (Trichinellida, Trichuridae). Heteroxynema sp. is cited for the first time from ancient material worldwide. The finding of Trichuris spp. in both rodents and other host samples from the area under study is indicative of the stability of the biological and environmental conditions for this nematode genus to establish in the Patagonian Early Holocene. The rodent host was assigned to an unknown species of Caviomorpha (Hystricognathi) that lived during the Pleistocenic transition in Patagonia.

  11. Rodent ultrasonic vocalizations are bound to active sniffing behavior

    Directory of Open Access Journals (Sweden)

    Yevgeniy B Sirotin

    2014-11-01

    Full Text Available During rodent active behavior, multiple orofacial sensorimotor behaviors, including sniffing and whisking, display rhythmicity in the theta range (~5-10 Hz. During specific behaviors, these rhythmic patterns interlock, such that execution of individual motor programs becomes dependent on the state of the others. Here we performed simultaneous recordings of the respiratory cycle and ultrasonic vocalization emission by adult rats and mice in social settings. We used automated analysis to examine the relationship between breathing patterns and vocalization over long time periods. Rat ultrasonic vocalizations (USVs, ’50 kHz’ were emitted within stretches of active sniffing (5−10 Hz and were largely absent during periods of passive breathing (1-4 Hz. Because ultrasound was tightly linked to the exhalation phase, the sniffing cycle segmented vocal production into discrete calls and imposed its theta rhythmicity on their timing. In turn, calls briefly prolonged exhalations, causing an immediate drop in sniffing rate. Similar results were obtained in mice. Our results show that ultrasonic vocalizations are an integral part of the rhythmic orofacial behavioral ensemble. This complex behavioral program is thus involved not only in active sensing but also in the temporal structuring of social communication signals. Many other social signals of mammals, including monkey calls and human speech, show structure in the theta range. Our work points to a mechanism for such structuring in rodent ultrasonic vocalizations.

  12. Functional evolution of the feeding system in rodents.

    Directory of Open Access Journals (Sweden)

    Philip G Cox

    Full Text Available The masticatory musculature of rodents has evolved to enable both gnawing at the incisors and chewing at the molars. In particular, the masseter muscle is highly specialised, having extended anteriorly to originate from the rostrum. All living rodents have achieved this masseteric expansion in one of three ways, known as the sciuromorph, hystricomorph and myomorph conditions. Here, we used finite element analysis (FEA to investigate the biomechanical implications of these three morphologies, in a squirrel, guinea pig and rat. In particular, we wished to determine whether each of the three morphologies is better adapted for either gnawing or chewing. Results show that squirrels are more efficient at muscle-bite force transmission during incisor gnawing than guinea pigs, and that guinea pigs are more efficient at molar chewing than squirrels. This matches the known diet of nuts and seeds that squirrels gnaw, and of grasses that guinea pigs grind down with their molars. Surprisingly, results also indicate that rats are more efficient as well as more versatile feeders than both the squirrel and guinea pig. There seems to be no compromise in biting efficiency to accommodate the wider range of foodstuffs and the more general feeding behaviour adopted by rats. Our results show that the morphology of the skull and masticatory muscles have allowed squirrels to specialise as gnawers and guinea pigs as chewers, but that rats are high-performance generalists, which helps explain their overwhelming success as a group.

  13. Studying autism in rodent models: reconciling endophenotypes with comorbidities.

    Directory of Open Access Journals (Sweden)

    Andrew eArgyropoulos

    2013-07-01

    Full Text Available Autism spectrum disorder (ASD patients commonly exhibit a variety of comorbid traits including seizures, anxiety, aggressive behavior, gastrointestinal problems, motor deficits, abnormal sensory processing and sleep disturbances for which the cause is unknown. These features impact negatively on daily life and can exaggerate the effects of the core diagnostic traits (social communication deficits and repetitive behaviors. Studying endophenotypes relevant to both core and comorbid features of ASD in rodent models can provide insight into biological mechanisms underlying these disorders. Here we review the characterization of endophenotypes in a selection of environmental, genetic and behavioural rodent models of ASD. In addition to exhibiting core ASD-like behaviours, each of these animal models display one or more endophenotypes relevant to comorbid features including altered sensory processing, seizure susceptibility, anxiety-like behaviour and disturbed motor functions, suggesting that these traits are indicators of altered biological pathways in ASD. However, the study of behaviours paralleling comorbid traits in animal models of ASD is an emerging field and further research is needed to assess altered gastrointestinal function, aggression and disorders of sleep onset across models. Future studies should include investigation of these endophenotypes in order to advance our understanding of the etiology of this complex disorder.

  14. New Insights from Rodent Models of Fatty Liver Disease

    Science.gov (United States)

    2011-01-01

    Abstract Rodent models of fatty liver disease are essential research tools that provide a window into disease pathogenesis and a testing ground for prevention and treatment. Models come in many varieties involving dietary and genetic manipulations, and sometimes both. High-energy diets that induce obesity do not uniformly cause fatty liver disease; this has prompted close scrutiny of specific macronutrients and nutrient combinations to determine which have the greatest potential for hepatotoxicity. At the same time, diets that do not cause obesity or the metabolic syndrome but do cause severe steatohepatitis have been exploited to study factors important to progressive liver injury, including cell death, oxidative stress, and immune activation. Rodents with a genetic predisposition to overeating offer yet another model in which to explore the evolution of fatty liver disease. In some animals that overeat, steatohepatitis can develop even without resorting to a high-energy diet. Importantly, these models and others have been used to document that aerobic exercise can prevent or reduce fatty liver disease. This review focuses primarily on lessons learned about steatohepatitis from manipulations of diet and eating behavior. Numerous additional insights about hepatic lipid metabolism, which have been gained from genetically engineered mice, are also mentioned. Antioxid. Redox Signal. 15, 535–550. PMID:21126212

  15. Causal evidence between monsoon and evolution of rhizomyine rodents.

    Science.gov (United States)

    López-Antoñanzas, Raquel; Knoll, Fabien; Wan, Shiming; Flynn, Lawrence J

    2015-03-11

    The modern Asian monsoonal systems are currently believed to have originated around the end of the Oligocene following a crucial step of uplift of the Tibetan-Himalayan highlands. Although monsoon possibly drove the evolution of many mammal lineages during the Neogene, no evidence thereof has been provided so far. We examined the evolutionary history of a clade of rodents, the Rhizomyinae, in conjunction with our current knowledge of monsoon fluctuations over time. The macroevolutionary dynamics of rhizomyines were analyzed within a well-constrained phylogenetic framework coupled with biogeographic and evolutionary rate studies. The evolutionary novelties developed by these rodents were surveyed in parallel with the fluctuations of the Indian monsoon so as to evaluate synchroneity and postulate causal relationships. We showed the existence of three drops in biodiversity during the evolution of rhizomyines, all of which reflected elevated extinction rates. Our results demonstrated linkage of monsoon variations with the evolution and biogeography of rhizomyines. Paradoxically, the evolution of rhizomyines was accelerated during the phases of weakening of the monsoons, not of strengthening, most probably because at those intervals forest habitats declined, which triggered extinction and progressive specialization toward a burrowing existence.

  16. A Practical Guide to Rodent Islet Isolation and Assessment

    Directory of Open Access Journals (Sweden)

    Carter Jeffrey D

    2009-12-01

    Full Text Available Abstract Pancreatic islets of Langerhans secrete hormones that are vital to the regulation of blood glucose and are, therefore, a key focus of diabetes research. Purifying viable and functional islets from the pancreas for study is an intricate process. This review highlights the key elements involved with mouse and rat islet isolation, including choices of collagenase, the collagenase digestion process, purification of islets using a density gradient, and islet culture conditions. In addition, this paper reviews commonly used techniques for assessing islet viability and function, including visual assessment, fluorescent markers of cell death, glucose-stimulated insulin secretion, and intracellular calcium measurements. A detailed protocol is also included that describes a common method for rodent islet isolation that our laboratory uses to obtain viable and functional mouse islets for in vitro study of islet function, beta-cell physiology, and in vivo rodent islet transplantation. The purpose of this review is to serve as a resource and foundation for successfully procuring and purifying high-quality islets for research purposes.

  17. Spatial memory tasks in rodents: what do they model?

    Science.gov (United States)

    Morellini, Fabio

    2013-10-01

    The analysis of spatial learning and memory in rodents is commonly used to investigate the mechanisms underlying certain forms of human cognition and to model their dysfunction in neuropsychiatric and neurodegenerative diseases. Proper interpretation of rodent behavior in terms of spatial memory and as a model of human cognitive functions is only possible if various navigation strategies and factors controlling the performance of the animal in a spatial task are taken into consideration. The aim of this review is to describe the experimental approaches that are being used for the study of spatial memory in rats and mice and the way that they can be interpreted in terms of general memory functions. After an introduction to the classification of memory into various categories and respective underlying neuroanatomical substrates, I explain the concept of spatial memory and its measurement in rats and mice by analysis of their navigation strategies. Subsequently, I describe the most common paradigms for spatial memory assessment with specific focus on methodological issues relevant for the correct interpretation of the results in terms of cognitive function. Finally, I present recent advances in the use of spatial memory tasks to investigate episodic-like memory in mice.

  18. Evaluating rodent motor functions: Which tests to choose?

    Science.gov (United States)

    Schönfeld, Lisa-Maria; Dooley, Dearbhaile; Jahanshahi, Ali; Temel, Yasin; Hendrix, Sven

    2017-12-01

    Damage to the motor cortex induced by stroke or traumatic brain injury (TBI) can result in chronic motor deficits. For the development and improvement of therapies, animal models which possess symptoms comparable to the clinical population are used. However, the use of experimental animals raises valid ethical and methodological concerns. To decrease discomfort by experimental procedures and to increase the quality of results, non-invasive and sensitive rodent motor tests are needed. A broad variety of rodent motor tests are available to determine deficits after stroke or TBI. The current review describes and evaluates motor tests that fall into three categories: Tests to evaluate fine motor skills and grip strength, tests for gait and inter-limb coordination and neurological deficit scores. In this review, we share our thoughts on standardized data presentation to increase data comparability between studies. We also critically evaluate current methods and provide recommendations for choosing the best behavioral test for a new research line. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The role of succulent halophytes in the water balance of salt marsh rodents.

    Science.gov (United States)

    Coulombe, Harry N

    1970-09-01

    The role of succulent halophytes in the water balance and ecology of salt marsh rodents is dependent upon an evaluation of the composition of the available sources and the physiological properties of their potential consumers. Studies of the osmotic properties of succulent halophytes from southern California coastal salt marshes are presented, together with experiments regarding the utilization of Common Pickleweed (Salicornia virginica L.) by indigenous populations of cricetid rodents (harvest mouse Reithrodontomys megalotis limicola Von Bloecker, and meadow-mouse Microtus californicus stephensi Von Bloecker). These data are discussed in relation to other available information concerning the ecology of coastal salt marshes, particularly in western North America.Extruded sap of Common Pickleweed was found to have a mean total osmotic pressure (TOP) of 1,450 mOsm/liter, with an average chloride ion content of 876 mEq/liter (about 70% of the TOP). A related species, Salicornia subterminale, had a slightly lower TOP (1,300 mOsm/liter), of which about 29% was accounted for by chloride ion concentration. Sea Blight (Suaeda fruticosa) was the only species in which the TOP correlated with the distance from the tide level; sap TOP increased away from the lagoon's edge. In both Sea Blight and Common Pickle weed, TOP was not directly related to chloride content, indicating the importance of other osmotically active solutes.Harvest mice were placed on three experimental regimes: 1) millet seeds only, 2) pickleweed only, and 3) pickleweed and millet seed. Meadow mice were tested on the last regime only. Harvest mice survived best on a strict millet seed diet; when Salicornia was consumed to a detectable extent, the mice did not survive. Meadow mice, however, could survive using Salicornia as a dietary source in conjunction with seeds. Kidney electrolyte concentrating abilities indicated that harvest mice should be able to utilize pickleweed; this was not confirmed in my

  20. Atlantic small-mammal: a dataset of communities of rodents and marsupials of the Atlantic forests of South America.

    Science.gov (United States)

    Bovendorp, Ricardo S; Villar, Nacho; de Abreu-Junior, Edson F; Bello, Carolina; Regolin, André L; Percequillo, Alexandre R; Galetti, Mauro

    2017-08-01

    The contribution of small mammal ecology to the understanding of macroecological patterns of biodiversity, population dynamics, and community assembly has been hindered by the absence of large datasets of small mammal communities from tropical regions. Here we compile the largest dataset of inventories of small mammal communities for the Neotropical region. The dataset reviews small mammal communities from the Atlantic forest of South America, one of the regions with the highest diversity of small mammals and a global biodiversity hotspot, though currently covering less than 12% of its original area due to anthropogenic pressures. The dataset comprises 136 references from 300 locations covering seven vegetation types of tropical and subtropical Atlantic forests of South America, and presents data on species composition, richness, and relative abundance (captures/trap-nights). One paper was published more than 70 yr ago, but 80% of them were published after 2000. The dataset comprises 53,518 individuals of 124 species of small mammals, including 30 species of marsupials and 94 species of rodents. Species richness averaged 8.2 species (1-21) per site. Only two species occurred in more than 50% of the sites (the common opossum, Didelphis aurita and black-footed pigmy rice rat Oligoryzomys nigripes). Mean species abundance varied 430-fold, from 4.3 to 0.01 individuals/trap-night. The dataset also revealed a hyper-dominance of 22 species that comprised 78.29% of all individuals captured, with only seven species representing 44% of all captures. The information contained on this dataset can be applied in the study of macroecological patterns of biodiversity, communities, and populations, but also to evaluate the ecological consequences of fragmentation and defaunation, and predict disease outbreaks, trophic interactions and community dynamics in this biodiversity hotspot. © 2017 by the Ecological Society of America.

  1. Advances in Rodent Research Missions on the International Space Station

    Science.gov (United States)

    Choi, S. Y.; Ronca, A.; Leveson-Gower, D.; Gong, C.; Stube, K.; Pletcher, D.; Wigley, C.; Beegle, J.; Globus, R. K.

    2016-01-01

    A research platform for rodent experiment on the ISS is a valuable tool for advancing biomedical research in space. Capabilities offered by the Rodent Research project developed at NASA Ames Research Center can support experiments of much longer duration on the ISS than previous experiments performed on the Space Shuttle. NASAs Rodent Research (RR)-1 mission was completed successfully and achieved a number of objectives, including validation of flight hardware, on-orbit operations, and science capabilities as well as support of a CASIS-sponsored experiment (Novartis) on muscle atrophy. Twenty C57BL6J adult female mice were launched on the Space-X (SpX) 4 Dragon vehicle, and thrived for up to 37 days in microgravity. Daily health checks of the mice were performed during the mission via downlinked video; all flight animals were healthy and displayed normal behavior, and higher levels of physical activity compared to ground controls. Behavioral analysis demonstrated that Flight and Ground Control mice exhibited the same range of behaviors, including eating, drinking, exploratory behavior, self- and allo-grooming, and social interactions indicative of healthy animals. The animals were euthanized on-orbit and select tissues were collected from some of the mice on orbit to assess the long-term sample storage capabilities of the ISS. In general, the data obtained from the flight mice were comparable to those from the three groups of control mice (baseline, vivarium and ground controls, which were housed in flight hardware), showing that the ISS has adequate capability to support long-duration rodent experiments. The team recovered 35 tissues from 40 RR-1 frozen carcasses, yielding 3300 aliquots of tissues to distribute to the scientific community in the U.S., including NASAs GeneLab project and scientists via Space Biology's Biospecimen Sharing Program Ames Life Science Data Archive. Tissues also were distributed to Russian research colleagues at the Institute for

  2. Rodent-borne diseases and their public health importance in Iran.

    Directory of Open Access Journals (Sweden)

    Mohammad Hasan Rabiee

    2018-04-01

    Full Text Available Rodents are reservoirs and hosts for several zoonotic diseases such as plague, leptospirosis, and leishmaniasis. Rapid development of industry and agriculture, as well as climate change throughout the globe, has led to change or increase in occurrence of rodent-borne diseases. Considering the distribution of rodents throughout Iran, the aim of this review is to assess the risk of rodent-borne diseases in Iran.We searched Google Scholar, PubMed, Science Direct, Scientific Information Database (SID, and Magiran databases up to September 2016 to obtain articles reporting occurrence of rodent-borne diseases in Iran and extract information from them. Out of 70 known rodent-borne diseases, 34 were reported in Iran: 17 (50% parasitic diseases, 13 (38% bacterial diseases, and 4 (12% viral diseases. Twenty-one out of 34 diseases were reported from both humans and rodents. Among the diseases reported in the rodents of Iran, plague, leishmaniasis, and hymenolepiasis were the most frequent. The most infected rodents were Rattus norvegicus (16 diseases, Mus musculus (14 diseases, Rattus rattus (13 diseases, Meriones persicus (7 diseases, Apodemus spp. (5 diseases, Tatera indica (4 diseases, Meriones libycus (3 diseases, Rhombomys opimus (3 diseases, Cricetulus migratorius (3 diseases, and Nesokia indica (2 diseases.The results of this review indicate the importance of rodent-borne diseases in Iran. Considering notable diversity of rodents and their extensive distribution throughout the country, it is crucial to pay more attention to their role in spreading infectious diseases for better control of the diseases.

  3. Rodent-borne diseases and their public health importance in Iran

    Science.gov (United States)

    Mahmoudi, Ahmad; Siahsarvie, Roohollah; Kryštufek, Boris; Mostafavi, Ehsan

    2018-01-01

    Background Rodents are reservoirs and hosts for several zoonotic diseases such as plague, leptospirosis, and leishmaniasis. Rapid development of industry and agriculture, as well as climate change throughout the globe, has led to change or increase in occurrence of rodent-borne diseases. Considering the distribution of rodents throughout Iran, the aim of this review is to assess the risk of rodent-borne diseases in Iran. Methodology/Principal finding We searched Google Scholar, PubMed, Science Direct, Scientific Information Database (SID), and Magiran databases up to September 2016 to obtain articles reporting occurrence of rodent-borne diseases in Iran and extract information from them. Out of 70 known rodent-borne diseases, 34 were reported in Iran: 17 (50%) parasitic diseases, 13 (38%) bacterial diseases, and 4 (12%) viral diseases. Twenty-one out of 34 diseases were reported from both humans and rodents. Among the diseases reported in the rodents of Iran, plague, leishmaniasis, and hymenolepiasis were the most frequent. The most infected rodents were Rattus norvegicus (16 diseases), Mus musculus (14 diseases), Rattus rattus (13 diseases), Meriones persicus (7 diseases), Apodemus spp. (5 diseases), Tatera indica (4 diseases), Meriones libycus (3 diseases), Rhombomys opimus (3 diseases), Cricetulus migratorius (3 diseases), and Nesokia indica (2 diseases). Conclusions/Significance The results of this review indicate the importance of rodent-borne diseases in Iran. Considering notable diversity of rodents and their extensive distribution throughout the country, it is crucial to pay more attention to their role in spreading infectious diseases for better control of the diseases. PMID:29672510

  4. Contribution of land use to rodent flea load distribution in the plague endemic area of Lushoto District, Tanzania.

    Science.gov (United States)

    Hieronimo, Proches; Kihupi, Nganga I; Kimaro, Didas N; Gulinck, Hubert; Mulungu, Loth S; Msanya, Balthazar M; Leirs, Herwig; Deckers, Jozef A

    2014-07-01

    Fleas associated with different rodent species are considered as the major vectors of bubonic plague, which is still rampant in different parts of the world. The objective of this study was to investigate the contribution of land use to rodent flea load distribution at fine scale in the plague endemic area of north-eastern Tanzania. Data was collected in three case areas namely, Shume, Lukozi and Mwangoi, differing in plague incidence levels. Data collection was carried out during both wet and dry seasons of 2012. Analysis of Variance and Boosted Regression Tree (BRT) statistical methods were used to clarify the relationships between fleas and specific land use characteristics. There was a significant variation (P ≤ 0.05) of flea indices in different land use types. Fallow and natural forest had higher flea indices whereas plantation forest mono-crop and mixed annual crops had the lowest flea indices among the aggregated land use types. The influence of individual land use types on flea indices was variable with fallow having a positive effect and land tillage showing a negative effect. The results also demonstrated a seasonal effect, part of which can be attributed to different land use practices such as application of pesticides, or the presence of grass strips around fields. These findings suggest that land use factors have a major influence on rodent flea abundance which can be taken as a proxy for plague infection risk. The results further point to the need for a comprehensive package that includes land tillage and crop type considerations on one hand and the associated human activities on the other, in planning and implementation of plague control interventions.

  5. High density of fox and cat faeces in kitchen gardens and resulting rodent exposure to Echinococcus multilocularis and Toxoplasma gondii.

    Science.gov (United States)

    Bastien, Matthieu; Vaniscotte, Amelie; Combes, Benoit; Umhang, Gerald; Germain, Estelle; Gouley, Valentin; Pierlet, Alice; Quintaine, Thomas; Forin-Wiart, Marie-Amelie; Villena, Isabelle; Aubert, Dominique; Boue, Franck; Poulle, Marie-Lazarine

    2018-03-08

    The faeces of the red fox, Vulpes vulpes (Linnaeus), and the domestic cat, Felis catus (Linnaeus), can be responsible for spreading eggs of Echinococcus multilocularis Leuckart, 1863 and oocysts of Toxoplasma gondii (Nicolle et Manceaux, 1908) into the environment. The accidental ingestion of these eggs or oocysts, through consumption of raw fruits or vegetables grown in or in contact with contaminated soil, can lead to alveolar echinococcosis (AE) or toxoplasmosis in humans. The present study provides a quantitative assessment of the faecal deposition by foxes and cats in kitchen gardens where fruits and vegetables are grown and its consequences for zoonosis transmission. The density of definitive host faeces is considered as one of the main factors in infection risk for intermediate hosts. The density of fox and cat faeces, as well as the prevalence of both AE and toxoplasmosis in rodent populations (contaminated by ingestion of eggs or oocysts), were compared within and outside kitchen gardens. Our results showed that the mean density of fox faeces did not significantly differ between kitchen gardens and habitat edges (0.29 ± 0.04 faeces/m 2 vs 0.22 ± 0.02 faeces/m 2 ), the latter being known as an area of high fox faeceal densities. The density of cat faeces was significantly higher within the kitchen garden than outside (0.86 ± 0.22 faeces/m 2 vs 0.04 ± 0.02 faeces/m 2 ). The sampled kitchen gardens might therefore be considered as possible hotspots for both fox and cat defecation. Of the 130 rodents trapped, 14% were infected by at least one species of fox or cat intestinal parasite. These rodents were significantly more often infected when they were exposed to a kitchen garden. These results suggest that the deposit of fox and cat faeces in kitchen gardens would significantly impact the risk of human exposure to E. multilocularis and T. gondii. and should be prevented using effective means.

  6. Stress in adolescence and drugs of abuse in rodent models: Role of dopamine, CRF, and HPA axis

    Science.gov (United States)

    Burke, Andrew R.; Miczek, Klaus A.

    2014-01-01

    Rationale Research on adolescence and drug abuse increased substantially in the past decade. However, drug-addiction related behaviors following stressful experiences during adolescence are less studied. We focus on rodent models of adolescent stress cross-sensitization to drugs of abuse. Objectives Review the ontogeny of behavior, dopamine, corticotropin-releasing factor (CRF), and the hypothalamic pituitary adrenal (HPA) axis in adolescent rodents. We evaluate evidence that stressful experiences during adolescence engender hypersensitivity to drugs of abuse and offer potential neural mechanisms. Results and Conclusions Much evidence suggests that final maturation of behavior, dopamine systems, and HPA axis occurs during adolescence. Stress during adolescence increases amphetamine- and ethanol-stimulated locomotion, preference, and self-administration under many conditions. The influence of adolescent stress on subsequent cocaine- and nicotine-stimulated locomotion and preference is less clear. The type of adolescent stress, temporal interval between stress and testing, species, sex, and the drug tested are key methodological determinants for successful cross-sensitization procedures. The sensitization of the mesolimbic dopamine system is proposed to underlie stress cross-sensitization to drugs of abuse in both adolescents and adults through modulation by CRF. Reduced levels of mesocortical dopamine appear to be a unique consequence of social stress during adolescence. Adolescent stress may reduce the final maturation of cortical dopamine through D2 dopamine receptor regulation of dopamine synthesis or glucocorticoid-facilitated pruning of cortical dopamine fibers. Certain rodent models of adolescent adversity are useful for determining neural mechanisms underlying the cross-sensitization to drugs of abuse. PMID:24370534

  7. Molecular Survey of Zoonotic Agents in Rodents and Other Small Mammals in Croatia.

    Science.gov (United States)

    Tadin, Ante; Tokarz, Rafal; Markotić, Alemka; Margaletić, Josip; Turk, Nenad; Habuš, Josipa; Svoboda, Petra; Vucelja, Marko; Desai, Aaloki; Jain, Komal; Lipkin, W Ian

    2016-02-01

    Croatia is a focus for many rodent-borne zoonosis. Here, we report a survey of 242 rodents and small mammals, including 43 Myodes glareolus, 131 Apodemus flavicollis, 53 Apodemus agrarius, three Apodemus sylvaticus, six Sorex araneus, four Microtus arvalis, one Microtus agrestis, and one Muscardinus avellanarius, collected at eight sites in Croatia over an 8-year period. Multiplex MassTag polymerase chain reaction (PCR) was used for detection of Borrelia, Rickettsia, Bartonella, Babesia, Ehrlichia, Anaplasma, Francisella tularensis, and Coxiella burnetii. Individual PCR assays were used for detection of Leptospira, lymphocytic choriomeningitis virus, orthopoxviruses, flaviviruses, hantaviruses, and Toxoplasma gondii. Of the rodents, 52 (21.5%) were infected with Leptospira, 9 (3.7%) with Borrelia miyamotoi, 5 (2%) with Borrelia afzelii, 29 (12.0%) with Bartonella, 8 (3.3%) with Babesia microti, 2 (0.8%) with Ehrlichia, 4 (1.7%) with Anaplasma, 2 (0.8%) with F. tularensis, 43 (17.8%) with hantaviruses, and 1 (0.4%) with an orthopoxvirus. Other agents were not detected. Multiple infections were found in 32 rodents (13.2%): dual infections in 26 rodents (10.7%), triple infections in four rodents (2.9%), and quadruple infections in two rodents (0.8%). Our findings indicate that rodents in Croatia harbor a wide range of bacteria and viruses that are pathogenic to humans. © The American Society of Tropical Medicine and Hygiene.

  8. An early warning system for IPM-based rodent control in smallholder farming systems in Tanzania

    DEFF Research Database (Denmark)

    Mwanjabe, Patrick S.; Leirs, Herwig

    1997-01-01

    numbers increased faster. Where abundant short rains were a normal condition returning every year, such effect was not clear. A method to assess rodent damage to germinating seedlings was found to be robust and can be used for monitoring rodent problems. Using this assessment technique, we showed...

  9. 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.

  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. an ecological study on rodents of natural vegetation and farm lands ...

    African Journals Online (AJOL)

    preferred customer

    habitat association of rodents was conducted in Siltie natural vegetation and nearby farmlands ... In each habitat type, one representative grid was selected for live trapping. In addition, rodents were also snap- trapped from these habitats. A total of 562 captures was made .... into seeds, leaves, roots, earthworms and arthro-.

  12. In vivo microCT imaging of rodent cerebral vasculature

    International Nuclear Information System (INIS)

    Seo, Youngho; Hasegawa, Bruce H; Hashimoto, Tomoki; Nuki, Yoshitsugu

    2008-01-01

    Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (I tube x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml -1 at 1.2 ml min -1 ) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel (∼85 μm) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid arteries and major cerebral blood vessels

  13. In vivo microCT imaging of rodent cerebral vasculature

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Youngho; Hasegawa, Bruce H [Center for Molecular and Functional Imaging, Department of Radiology, University of California, San Francisco, CA 94143 (United States); Hashimoto, Tomoki; Nuki, Yoshitsugu [Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143 (United States)], E-mail: youngho.seo@radiology.ucsf.edu

    2008-04-07

    Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (I{sub tube} x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml{sup -1} at 1.2 ml min{sup -1}) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel ({approx}85 {mu}m) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid

  14. Neurobiology of rodent self-grooming and its value for translational neuroscience.

    Science.gov (United States)

    Kalueff, Allan V; Stewart, Adam Michael; Song, Cai; Berridge, Kent C; Graybiel, Ann M; Fentress, John C

    2016-01-01

    Self-grooming is a complex innate behaviour with an evolutionarily conserved sequencing pattern and is one of the most frequently performed behavioural activities in rodents. In this Review, we discuss the neurobiology of rodent self-grooming, and we highlight studies of rodent models of neuropsychiatric disorders--including models of autism spectrum disorder and obsessive compulsive disorder--that have assessed self-grooming phenotypes. We suggest that rodent self-grooming may be a useful measure of repetitive behaviour in such models, and therefore of value to translational psychiatry. Assessment of rodent self-grooming may also be useful for understanding the neural circuits that are involved in complex sequential patterns of action.

  15. Helminth Infections of Rodents and Their Zoonotic Importance in Boyer-Ahmad District, Southwestern Iran.

    Science.gov (United States)

    Ranjbar, Mohammad Javad; Sarkari, Bahador; Mowlavi, Gholam Reza; Seifollahi, Zeinab; Moshfe, Abdolali; Abdolahi Khabisi, Samaneh; Mobedi, Iraj

    2017-01-01

    Rodents are considered as reservoirs of various zoonotic diseases including helminthic infections. The current study aimed to evaluate the prevalence of helminth infections in rodents, in Boyer-Ahmad district, Southwestern Iran. Overall, 52 rodents were captured from various areas of the district by Sherman live traps. The animals were then euthanized and dissected. During necropsy, each organ was examined macroscopically for presence of any cyst or visible parasite. The gastrointestinal tract was removed and their contents were evaluated for larva or adult worms. Trichinella larvae in the rodents' muscles were investigated by both digestion and pathological methods. Twenty-eight (53.8%) of the trapped rodents were male. The rodents were including 25 (48.1%) Meriones persicus , 1(1.9%) Calomyscus bailwardi , 1 (1.9%) Arvicola terresterris , 7 (13.5%) Rattus rattus , 8 (15.4%) R. norvegicus , and 10 (19.2%) Apodemus sylvaticus . Of them, 38 (73.0%) were infected with at least one helminth. Collected rodents were infected with Hymenolepis diminuta (50%), Hymenolepis nana fraterna (28.8%), Skrjabinotaenia sp. (15.4%), Anoplocephalidae sp. (15.4%), Cysticercus fasciolaris (5.8%), Trichuris muris (36.5%), Aspiculuris tetraptera (15.4%), Syphacia sp. (5.7%), Rictularia sp. (15.4%), Trichostrongylus sp. (3.8%), and Gongylonema sp. (3.8%). M. persicus was the most (84%) infected rodent, yet the differences between rodent genus and helminth infectivity were not statistically significant ( P >0.05). The rodents in Boyer-Ahmad district are infected with different helminths infections that some of them are recognized as threat to human health.

  16. Females of the communally breeding rodent, Octodon degus, transfer antibodies to their offspring during pregnancy and lactation.

    Science.gov (United States)

    Becker, María Inés; De Ioannes, Alfredo E; León, Cecilia; Ebensperger, Luis A

    2007-06-01

    Females in numerous rodent species engage in communal nesting and breeding, meaning that they share a nest to rear their young together. One potential benefit to communally nesting mothers is that infants improve their immunocompetence. Thus, suckling from two or more females might provide newborns with a more diverse array of antibodies and defensive cells. As a first step toward testing the immunocompetence hypothesis, we assessed whether female degus (Octodon degus), a communally nesting and breeding caviomorph rodent, transfer immunoglobulins to their young through the yolk sac or placenta while in the uterus and, during lactation, through milk. With this aim, adult degu females were immunized with four antigens, including two mollusk hemocyanins from Concholepas and Megathura (CCH and KLH, respectively), porcine thyroglobulin and tetanus toxoid. Specific antibodies against the experimental antigens were used to track the origin of antibodies in the young. To establish the presence of specific antibodies of IgG and IgA isotypes in sera and milk of animals, an indirect enzyme-linked immunosorbent assay (ELISA) was developed. Degu females produced specific antibodies against antigens not found in their natural environment, and mothers were able to transfer the induced antibodies to their litters during pregnancy (IgG) and during lactation (IgA). However, we recorded only limited evidence of degu offspring acquiring antibodies from lactating mothers other than their own, giving little support to the increased immunocompetence hypothesis.

  17. Translational Rodent Paradigms to Investigate Neuromechanisms Underlying Behaviors Relevant to Amotivation and Altered Reward Processing in Schizophrenia.

    Science.gov (United States)

    Young, Jared W; Markou, Athina

    2015-09-01

    Amotivation and reward-processing deficits have long been described in patients with schizophrenia and considered large contributors to patients' inability to integrate well in society. No effective treatments exist for these symptoms, partly because the neuromechanisms mediating such symptoms are poorly understood. Here, we propose a translational neuroscientific approach that can be used to assess reward/motivational deficits related to the negative symptoms of schizophrenia using behavioral paradigms that can also be conducted in experimental animals. By designing and using objective laboratory behavioral tools that are parallel in their parameters in rodents and humans, the neuromechanisms underlying behaviors with relevance to these symptoms of schizophrenia can be investigated. We describe tasks that measure the motivation of rodents to expend physical and cognitive effort to gain rewards, as well as probabilistic learning tasks that assess both reward learning and feedback-based decision making. The latter tasks are relevant because of demonstrated links of performance deficits correlating with negative symptoms in patients with schizophrenia. These tasks utilize operant techniques in order to investigate neural circuits targeting a specific domain across species. These tasks therefore enable the development of insights into altered mechanisms leading to negative symptom-relevant behaviors in patients with schizophrenia. Such findings will then enable the development of targeted treatments for these altered neuromechanisms and behaviors seen in schizophrenia. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Nematode parasites of marsupials and small rodents from the Brazilian Atlantic Forest in the State of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Delir Corrêa Gomes

    2003-12-01

    Full Text Available Nematodes from opossums and rodents captured in the Brazilian Atlantic Forest in the State of Rio de Janeiro, Brazil were studied. From the opossums Didelphis aurita Weid-Neuweid, 1826 and Philander opossum (Linnaeus, 1758 the following nematode species were recovered: Viannaia hamata Travassos, 1914, Aspidodera raillieti Travassos, 1913, Cruzia tentaculata (Rudolphi, 1819, Travassos, 1917, Turgida turgida (Rudolphi, 1819 Travassos, 1919, Gongylonemoides marsupialis (Vaz & Pereira, 1934 Freitas & Lent, 1937, Viannaia viannai Travassos, 1914, Spirura guianensis (Ortlepp, 1924 Chitwood, 1938 and from the rodents Akodon cursor (Winger, 1887, Nectomys squamipes (Brants, 1827, Oligoryzomys eliurus (Wagner, 1845 and Oryzomys intermedius (Leche, 1886: Hassalstrongylus epsilon (Travassos, 1937 Durette-Desset, 1971, Syphacia obvelata (Rudolphi, 1802 Seurat, 1916, S. venteli Travassos, 1937, Physaloptera bispiculata Vaz & Pereira, 1935, Litomosoides carinii (Travassos, 1919 Vaz, 1934, Viannaia viannai, Hassalstrongylus epsilon, H. zeta (Travassos, 1937 Durette-Desset, 1971, Stilestrongylus aculeata (Travassos, 1918 Durette-Desset, 1971 S. eta (Travassos, 1937 Durette-Desset, 1971. Highest worm burdens and prevalences were those related to Cruzia tentaculata in marsupials. Stilestrongylus aculeata was referred for the first time in Akodon cursor.

  19. Species difference in metabolism of inhaled butadiene

    International Nuclear Information System (INIS)

    Sabourin, P.J.; Dahl, A.R.; Bechtold, W.E.; Henderson, R.F.; Burka, L.T.

    1991-01-01

    Chronic exposure of B6C3F 1 mice and Sprague-Dawley rats to butadiene (BD) produced a very high incidence of cancer in mice while the incidence in rats was much lower with different tissues affected. Studies at this institute indicate that for equivalent exposures, the blood BD epoxide concentrations in mice are 5-fold higher than in rats and > 10-fold higher than in Cynomolgus monkeys. In this study, the profiles of urinary metabolites of butadiene were determined in Cynomolgus monkeys, F344/N rats, Sprague Dawley rats, B6C3F 1 mice and Syrian hamsters, species containing widely divergent hepatic epoxide hydrolase (EH) activities. Animals were exposed for 2 hr to 8,000 ppm [ 14 C]BD and 24-hr urine samples were analyzed for metabolites. Two major urinary metabolites were identified, N-acetyl-S-(-1(or 2)-3-butene-2(or 1)-ol)cysteine (1) and N-acetyl-S-(-4-butane-1,2-diol)cysteine (2). Monkeys exposed by inhalation produced primarily metabolite 2, while rodent species produced 1-4 times as much of 1 compared to 2. The ratio of 2/1 formation was related to the hepatic epoxide hydrolase activity in different species. The high 2/1 ratio in monkeys was consistent with the lower blood epoxide levels in this species. If BD metabolism by humans is similar to that in the monkey, exposure of humans to BD may result in lower tissue concentrations of reactive metabolites than an equivalent exposure of rodents. This has important implications for assessing the risk to humans of BD exposure based on rodent studies

  20. Behavioral effects of developmental methylmercury drinking water exposure in rodents.

    Science.gov (United States)

    Bisen-Hersh, Emily B; Farina, Marcelo; Barbosa, Fernando; Rocha, Joao B T; Aschner, Michael

    2014-04-01

    Early methylmercury (MeHg) exposure can have long-lasting consequences likely arising from impaired developmental processes, the outcome of which has been exposed in several longitudinal studies of affected populations. Given the large number of newborns at an increased risk of learning disabilities associated with in utero MeHg exposure, it is important to study neurobehavioral alterations using ecologically valid and physiologically relevant models. This review highlights the benefits of using the MeHg drinking water exposure paradigm and outlines behavioral outcomes arising from this procedure in rodents. Combination treatments that exacerbate or ameliorate MeHg-induced effects, and possible molecular mechanisms underlying behavioral impairment are also discussed. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. Transmission of Guanarito and Pirital Viruses among Wild Rodents, Venezuela

    Science.gov (United States)

    Milazzo, Mary L.; Cajimat, Maria N.B.; Duno, Gloria; Duno, Freddy; Utrera, Antonio

    2011-01-01

    Samples from rodents captured on a farm in Venezuela in February 1997 were tested for arenavirus, antibody against Guanarito virus (GTOV), and antibody against Pirital virus (PIRV). Thirty-one (48.4%) of 64 short-tailed cane mice (Zygodontomys brevicauda) were infected with GTOV, 1 Alston’s cotton rat (Sigmodon alstoni) was infected with GTOV, and 36 (64.3%) of 56 other Alston’s cotton rats were infected with PIRV. The results of analyses of field and laboratory data suggested that horizontal transmission is the dominant mode of GTOV transmission in Z. brevicauda mice and that vertical transmission is an important mode of PIRV transmission in S. alstoni rats. The results also suggested that bodily secretions and excretions from most GTOV-infected short-tailed cane mice and most PIRV-infected Alston’s cotton rats may transmit the viruses to humans. PMID:22172205

  2. Odor supported place cell model and goal navigation in rodents

    DEFF Research Database (Denmark)

    Kulvicius, Tomas; Tamosiunaite, Minija; Ainge, James

    2008-01-01

    Experiments with rodents demonstrate that visual cues play an important role in the control of hippocampal place cells and spatial navigation. Nevertheless, rats may also rely on auditory, olfactory and somatosensory stimuli for orientation. It is also known that rats can track odors or self......-generated scent marks to find a food source. Here we model odor supported place cells by using a simple feed-forward network and analyze the impact of olfactory cues on place cell formation and spatial navigation. The obtained place cells are used to solve a goal navigation task by a novel mechanism based on self......-marking by odor patches combined with a Q-learning algorithm. We also analyze the impact of place cell remapping on goal directed behavior when switching between two environments. We emphasize the importance of olfactory cues in place cell formation and show that the utility of environmental and self...

  3. Modelling the emergence of rodent filial huddling from physiological huddling

    Science.gov (United States)

    Wilson, Stuart P.

    2017-11-01

    Huddling behaviour in neonatal rodents reduces the metabolic costs of physiological thermoregulation. However, animals continue to huddle into adulthood, at ambient temperatures where they are able to sustain a basal metabolism in isolation from the huddle. This `filial huddling' in older animals is known to be guided by olfactory rather than thermal cues. The present study aimed to test whether thermally rewarding contacts between young mice, experienced when thermogenesis in brown adipose fat tissue (BAT) is highest, could give rise to olfactory preferences that persist as filial huddling interactions in adults. To this end, a simple model was constructed to fit existing data on the development of mouse thermal physiology and behaviour. The form of the model that emerged yields a remarkable explanation for filial huddling; associative learning maintains huddling into adulthood via processes that reduce thermodynamic entropy from BAT metabolism and increase information about social ordering among littermates.

  4. Identification of rodent homologs of hepatitis C virus and pegiviruses

    DEFF Research Database (Denmark)

    Kapoor, Amit; Simmonds, Peter; Scheel, Troels K H

    2013-01-01

    UNLABELLED: Hepatitis C virus (HCV) and human pegivirus (HPgV or GB virus C) are globally distributed and infect 2 to 5% of the human population. The lack of tractable-animal models for these viruses, in particular for HCV, has hampered the study of infection, transmission, virulence, immunity...... into the origins of human infections and enhances our ability to study their pathogenesis and explore preventive and therapeutic interventions. Horses are the only reported host of nonprimate homologs of hepatitis C virus (HCV). Here, we report the discovery of HCV-like viruses in wild rodents. The majority of HCV...... of small-animal models for HCV, the most common infectious cause of liver failure and hepatocellular carcinoma after hepatitis B virus, and help to explore the health relevance of the highly prevalent human pegiviruses....

  5. Osseointegration of biochemically modified implants in an osteoporosis rodent model

    Directory of Open Access Journals (Sweden)

    B Stadlinger

    2013-07-01

    Full Text Available The present study examined the impact of implant surface modifications on osseointegration in an osteoporotic rodent model. Sandblasted, acid-etched titanium implants were either used directly (control or were further modified by surface conditioning with NaOH or by coating with one of the following active agents: collagen/chondroitin sulphate, simvastatin, or zoledronic acid. Control and modified implants were inserted into the proximal tibia of aged ovariectomised (OVX osteoporotic rats (n = 32/group. In addition, aged oestrogen competent animals received either control or NaOH conditioned implants. Animals were sacrificed 2 and 4 weeks post-implantation. The excised tibiae were utilised for biomechanical and morphometric readouts (n = 8/group/readout. Biomechanical testing revealed at both time points dramatically reduced osseointegration in the tibia of oestrogen deprived osteoporotic animals compared to intact controls irrespective of NaOH exposure. Consistently, histomorphometric and microCT analyses demonstrated diminished bone-implant contact (BIC, peri-implant bone area (BA, bone volume/tissue volume (BV/TV and bone-mineral density (BMD in OVX animals. Surface coating with collagen/chondroitin sulphate had no detectable impact on osseointegration. Interestingly, statin coating resulted in a transient increase in BIC 2 weeks post-implantation; which, however, did not correspond to improvement of biomechanical readouts. Local exposure to zoledronic acid increased BIC, BA, BV/TV and BMD at 4 weeks. Yet this translated only into a non-significant improvement of biomechanical properties. In conclusion, this study presents a rodent model mimicking severely osteoporotic bone. Contrary to the other bioactive agents, locally released zoledronic acid had a positive impact on osseointegration albeit to a lesser extent than reported in less challenging models.

  6. A checklist of the helminth parasites of sympatric rodents from two Mayan villages in Yucatán, México.

    Science.gov (United States)

    Panti-May, JesÚs Alonso; Digiani, MarÍa Celina; Palomo-Arjona, Eduardo Emir; Gurubel-gonzÁlez, Yessica Margely; Navone, Graciela T; Williams, Carlos Machain-; HernÁndez-Betancourt, Silvia F; Robles, MarÍa Del Rosario

    2018-04-05

    In this survey, 19 species of helminths including Cestoda (Davaineidae, Hymenolepididae, and Taeniidae), Acanthocephala (Oligacanthorhynchidae), and Nematoda (Trichuridae, Ornithostrongylidae, Heligmonellidae, Oxyuridae, and Gongylonematidae) from Rattus rattus, Mus musculus, Sigmodon toltecus, Heteromys gaumeri, and Peromyscus yucatanicus in two Mayan villages in Yucatán, México, were recorded. Ten species of helminths were collected in both localities. The highest species richness was recorded in R. rattus from Xkalakdzonot (6 taxa). Twelve species are new records for Yucatán and two are registered for the first time in México. This survey constitutes the first checklist of helminth parasites in small rodents in the south-southeast of México.

  7. Parasitic arthropods of some wild rodents from Juréia-Itatins Ecological Station, State of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Bossi David Eduardo Paolinetti

    2002-01-01

    Full Text Available A study of the associations between three species of rodents in the Atlantic forest and their parasitic arthropods was undertaken at the Juréia-Itatins Ecological Station, located in the State of São Paulo, Southeastern Brazil, from March 1989 to February 1990. Individuals of three species, Oryzomys russatus, Proechimys iheringi and Nectomys squamipes were captured and examined for ectoparasites. Eleven species of parasitic arthropods were found, including four species of insects and seven of Acari. Parasitism intensity, phenology, and rainfall were positively correlated with the abundance of the ectoparasites and their hosts. The most abundant host was O. russatus (Muridae: Sigmodontinae, and the most common parasite on it was the laelapid mite Gigantolaelaps oudemansi. The cuterebrid Metacuterebra apicalis caused myiasis in O. russatus. A mutualistic association between the staphylinid beetle Amblyopinus sp. and its host P. iheringi (Echimyidae was observed. The few N. squamipes captured had small numbers of ectoparasites.

  8. Genotoxic Changes to Rodent Cells Exposed in Vitro to Tungsten, Nickel, Cobalt and Iron

    Directory of Open Access Journals (Sweden)

    Stephanie Bardack

    2014-03-01

    Full Text Available Tungsten-based materials have been proposed as replacements for depleted uranium in armor-penetrating munitions and for lead in small-arms ammunition. A recent report demonstrated that a military-grade composition of tungsten, nickel, and cobalt induced a highly-aggressive, metastatic rhabdomyosarcoma when implanted into the leg muscle of laboratory rats to simulate a shrapnel wound. The early genetic changes occurring in response to embedded metal fragments are not known. In this study, we utilized two cultured rodent myoblast cell lines, exposed to soluble tungsten alloys and the individual metals comprising the alloys, to study the genotoxic effects. By profiling cell transcriptomes using microarray, we found slight, yet distinct and unique, gene expression changes in rat myoblast cells after 24 h metal exposure, and several genes were identified that correlate with impending adverse consequences of ongoing exposure to weapons-grade tungsten alloy. These changes were not as apparent in the mouse myoblast cell line. This indicates a potential species difference in the cellular response to tungsten alloy, a hypothesis supported by current findings with in vivo model systems. Studies examining genotoxic-associated gene expression changes in cells from longer exposure times are warranted.

  9. Consequences of organ choice in describing bacterial pathogen assemblages in a rodent population.

    Science.gov (United States)

    Villette, P; Afonso, E; Couval, G; Levret, A; Galan, M; Tatard, C; Cosson, J F; Giraudoux, P

    2017-10-01

    High-throughput sequencing technologies now allow for rapid cost-effective surveys of multiple pathogens in many host species including rodents, but it is currently unclear if the organ chosen for screening influences the number and identity of bacteria detected. We used 16S rRNA amplicon sequencing to identify bacterial pathogens in the heart, liver, lungs, kidneys and spleen of 13 water voles (Arvicola terrestris) collected in Franche-Comté, France. We asked if bacterial pathogen assemblages within organs are similar and if all five organs are necessary to detect all of the bacteria present in an individual animal. We identified 24 bacteria representing 17 genera; average bacterial richness for each organ ranged from 1·5 ± 0·4 (mean ± standard error) to 2·5 ± 0·4 bacteria/organ and did not differ significantly between organs. The average bacterial richness when organ assemblages were pooled within animals was 4·7 ± 0·6 bacteria/animal; Operational Taxonomic Unit accumulation analysis indicates that all five organs are required to obtain this. Organ type influences bacterial assemblage composition in a systematic way (PERMANOVA, 999 permutations, pseudo-F 4,51 = 1·37, P = 0·001). Our results demonstrate that the number of organs sampled influences the ability to detect bacterial pathogens, which can inform sampling decisions in public health and wildlife ecology.

  10. A cell kinetic model of granulopoiesis under radiation exposure: Extension from rodents to canines and humans

    International Nuclear Information System (INIS)

    Hu, S.; Cucinotta, F. A.

    2011-01-01

    As significant ionising radiation exposure will occur during prolonged space travel in future, it is essential to understand their adverse effects on the radiosensitive organ systems that are important for immediate survival of humans, e.g. the haematopoietic system. In this paper, a bio-mathematical model of granulopoiesis is used to analyse the granulocyte changes seen in the blood of mammalians under acute and continuous radiation exposure. This is one of a set of haematopoietic models that have been successfully utilised to simulate and interpret the experimental data of acute and chronic radiation on rodents. Extension to canine and human systems indicates that the results of the model are consistent with the cumulative experimental and empirical data from various sources, implying the potential to integrate them into one united model system to monitor the haematopoietic response of various species under irradiation. The suppression of granulocytes' level of a space traveller under chronic stress of low-dose irradiation as well as the granulopoietic response when encountering a historically large solar particle event is also discussed. (authors)

  11. Amazonian phylogeography: mtDNA sequence variation in arboreal echimyid rodents (Caviomorpha).

    Science.gov (United States)

    da Silva, M N; Patton, J L

    1993-09-01

    Patterns of evolutionary relationships among haplotype clades of sequences of the mitochondrial cytochrome b DNA gene are examined for five genera of arboreal rodents of the Caviomorph family Echimyidae from the Amazon Basin. Data are available for 798 bp of sequence from a total of 24 separate localities in Peru, Venezuela, Bolivia, and Brazil for Mesomys, Isothrix, Makalata, Dactylomys, and Echimys. Sequence divergence, corrected for multiple hits, is extensive, ranging from less than 1% for comparisons within populations of over 20% among geographic units within genera. Both the degree of differentiation and the geographic patterning of the variation suggest that more than one species composes the Amazonian distribution of the currently recognized Mesomys hispidus, Isothrix bistriata, Makalata didelphoides, and Dactylomys dactylinus. There is general concordance in the geographic range of haplotype clades for each of these taxa, and the overall level of differentiation within them is largely equivalent. These observations suggest that a common vicariant history underlies the respective diversification of each genus. However, estimated times of divergence based on the rate of third position transversion substitutions for the major clades within each genus typically range above 1 million years. Thus, allopatric isolation precipitating divergence must have been considerably earlier than the late Pleistocene forest fragmentation events commonly invoked for Amazonian biota.

  12. Architecture of interstitial nodal spaces in the rodent renal inner medulla.

    Science.gov (United States)

    Gilbert, Rebecca L; Pannabecker, Thomas L

    2013-09-01

    Every collecting duct (CD) of the rat inner medulla is uniformly surrounded by about four abutting ascending vasa recta (AVR) running parallel to it. One or two ascending thin limbs (ATLs) lie between and parallel to each abutting AVR pair, opposite the CD. These structures form boundaries of axially running interstitial compartments. Viewed in transverse sections, these compartments appear as four interstitial nodal spaces (INSs) positioned symmetrically around each CD. The axially running compartments are segmented by interstitial cells spaced at regular intervals. The pairing of ATLs and CDs bounded by an abundant supply of AVR carrying reabsorbed water, NaCl, and urea make a strong argument that the mixing of NaCl and urea within the INSs and countercurrent flows play a critical role in generating the inner medullary osmotic gradient. The results of this study fully support that hypothesis. We quantified interactions of all structures comprising INSs along the corticopapillary axis for two rodent species, the Munich-Wistar rat and the kangaroo rat. The results showed remarkable similarities in the configurations of INSs, suggesting that the structural arrangement of INSs is a highly conserved architecture that plays a fundamental role in renal function. The number density of INSs along the corticopapillary axis directly correlated with a loop population that declines exponentially with distance below the outer medullary-inner medullary boundary. The axial configurations were consistent with discrete association between near-bend loop segments and INSs and with upper loop segments lying distant from INSs.

  13. An integrated approach for prospectively investigating a mode-of-action for rodent liver effects

    International Nuclear Information System (INIS)

    LeBaron, Matthew J.; Geter, David R.; Rasoulpour, Reza J.; Gollapudi, B. Bhaskar; Thomas, Johnson; Murray, Jennifer; Kan, H. Lynn; Wood, Amanda J.; Elcombe, Cliff; Vardy, Audrey; McEwan, Jillian; Terry, Claire; Billington, Richard

    2013-01-01

    Registration of new plant protection products (e.g., herbicide, insecticide, or fungicide) requires comprehensive mammalian toxicity evaluation including carcinogenicity studies in two species. The outcome of the carcinogenicity testing has a significant bearing on the overall human health risk assessment of the substance and, consequently, approved uses for different crops across geographies. In order to understand the relevance of a specific tumor finding to human health, a systematic, transparent, and hypothesis-driven mode of action (MoA) investigation is, appropriately, an expectation by the regulatory agencies. Here, we describe a novel approach of prospectively generating the MoA data by implementing additional end points to the standard guideline toxicity studies with sulfoxaflor, a molecule in development. This proactive MoA approach results in a more robust integration of molecular with apical end points while minimizing animal use. Sulfoxaflor, a molecule targeting sap-feeding insects, induced liver effects (increased liver weight due to hepatocellular hypertrophy) in an initial palatability probe study for selecting doses for subsequent repeat-dose dietary studies. This finding triggered the inclusion of dose-response investigations of the potential key events for rodent liver carcinogenesis, concurrent with the hazard assessment studies. As predicted, sulfoxaflor induced liver tumors in rats and mice in the bioassays. The MoA data available by the time of the carcinogenicity finding supported the conclusion that the carcinogenic potential of sulfoxaflor was due to CAR/PXR nuclear receptor activation with subsequent hepatocellular proliferation. This MoA was not considered to be relevant to humans as sulfoxaflor is unlikely to induce hepatocellular proliferation in humans and therefore would not be a human liver carcinogen. - Highlights: • We prospectively generated MoA data into standard guideline toxicity studies. • A proactive MoA approach

  14. An integrated approach for prospectively investigating a mode-of-action for rodent liver effects

    Energy Technology Data Exchange (ETDEWEB)

    LeBaron, Matthew J., E-mail: MJLeBaron@dow.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Geter, David R., E-mail: dave.geter@gmail.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Rasoulpour, Reza J. [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Gollapudi, B. Bhaskar, E-mail: BBGollapudi@dow.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Thomas, Johnson, E-mail: JThomas4@dow.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Murray, Jennifer, E-mail: AMurray@dow.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Kan, H. Lynn, E-mail: HLKan@dow.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Wood, Amanda J., E-mail: AJWood@dow.com [Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI, 48674 (United States); Elcombe, Cliff, E-mail: CliffElcombe@cxrbiosciences.com [CXR Biosciences, 2 James Lindsay Place, Dundee Technopole, Dundee, DD1 5JJ, Scotland (United Kingdom); Vardy, Audrey, E-mail: audrey_vardy@europe.bd.com [CXR Biosciences, 2 James Lindsay Place, Dundee Technopole, Dundee, DD1 5JJ, Scotland (United Kingdom); McEwan, Jillian, E-mail: jillian.mcewan@rtmcewan.co.uk [CXR Biosciences, 2 James Lindsay Place, Dundee Technopole, Dundee, DD1 5JJ, Scotland (United Kingdom); Terry, Claire, E-mail: CTerry@dow.com [Dow AgroSciences, Abingdon, Oxfordshire (United Kingdom); Billington, Richard, E-mail: RBillington@dow.com [Dow AgroSciences, Abingdon, Oxfordshire (United Kingdom)

    2013-07-15

    Registration of new plant protection products (e.g., herbicide, insecticide, or fungicide) requires comprehensive mammalian toxicity evaluation including carcinogenicity studies in two species. The outcome of the carcinogenicity testing has a significant bearing on the overall human health risk assessment of the substance and, consequently, approved uses for different crops across geographies. In order to understand the relevance of a specific tumor finding to human health, a systematic, transparent, and hypothesis-driven mode of action (MoA) investigation is, appropriately, an expectation by the regulatory agencies. Here, we describe a novel approach of prospectively generating the MoA data by implementing additional end points to the standard guideline toxicity studies with sulfoxaflor, a molecule in development. This proactive MoA approach results in a more robust integration of molecular with apical end points while minimizing animal use. Sulfoxaflor, a molecule targeting sap-feeding insects, induced liver effects (increased liver weight due to hepatocellular hypertrophy) in an initial palatability probe study for selecting doses for subsequent repeat-dose dietary studies. This finding triggered the inclusion of dose-response investigations of the potential key events for rodent liver carcinogenesis, concurrent with the hazard assessment studies. As predicted, sulfoxaflor induced liver tumors in rats and mice in the bioassays. The MoA data available by the time of the carcinogenicity finding supported the conclusion that the carcinogenic potential of sulfoxaflor was due to CAR/PXR nuclear receptor activation with subsequent hepatocellular proliferation. This MoA was not considered to be relevant to humans as sulfoxaflor is unlikely to induce hepatocellular proliferation in humans and therefore would not be a human liver carcinogen. - Highlights: • We prospectively generated MoA data into standard guideline toxicity studies. • A proactive MoA approach

  15. Expression of the p16{sup INK4a} tumor suppressor gene in rodent lung tumors

    Energy Technology Data Exchange (ETDEWEB)

    Swafford, D.S.; Tesfaigzi, J.; Belinsky, S.A.

    1995-12-01

    Aberrations on the short arm of chromosome 9 are among the earliest genetic changes in human cancer. p16{sup INK4a} is a candidate tumor suppressor gene that lies within human 9p21, a chromosome region associated with frequent loss of heterozygosity in human lung tumors. The p16{sup INK4a} protein functions as an inhibitor of cyclin D{sub 1}-dependent kinases that phosphorylate the retinoblastoma (Rb) tumor suppressor gene product enabling cell-cycle progression. Thus, overexpression of cyclin D{sub 1}, mutation of cyclin-dependent kinase genes, or loss of p16{sup INK4a} function, can all result in functional inactivation of Rb. Inactivation of Rb by mutation or deletion can result in an increase in p16{sup INK4a} transcription, suggesting that an increased p16{sup INK4a} expression in a tumor cell signals dysfunction of the pathway. The p16{sup (INK4a)} gene, unlike some tumor suppressor genes, is rarely inactivated by mutation. Instead, the expression of this gene is suppressed in some human cancers by hypermethylation of the CpG island within the first exon or by homozygous deletion: 686. Chromosome losses have been observed at 9p21 syntenic loci in tumors of the mouse and rat, two species often used as animal models for pulmonary carcinogenesis. Expression of p16{sup INK4a} is lost in some mouse tumor cell lines, often due to homozygous deletion. These observations indicate that p16{sup INK4a} dysfunction may play a role in the development of neoplasia in rodents as well as humans. The purpose of the current investigation was to define the extent to which p16{sup INK4a} dysfunction contributes to the development of rodent lung tumors and to determine the mechanism of inactivation of the gene. There is no evidence to suggest a loss of function of the p16{sup INK4a} tumor suppressor gene in these primary murine lung tumors by mutation, deletion, or methylation.

  16. Diet of a sigmodontine rodent assemblage in a Peruvian montane forest.

    Science.gov (United States)

    Sahley, Catherine Teresa; Cervantes, Klauss; Pacheco, Victor; Salas, Edith; Paredes, Diego; Alonso, Alfonso

    2015-09-29

    Knowledge of feeding habits of small rodents is necessary for understanding food webs, trophic structure, and plant-animal interactions in Neotropical forests. Despite several studies that have investigated community structure and feeding behavior of rodents, large gaps remain in our understanding of their guild occupancy. Our objective was to investigate the diets of 7 species of small (de los hábitos alimenticios de roedores pequeños es necesario para comprender cadenas alimenticias, estructura trófica, e interacciones planta-animal en los bosques neotropicales. A pesar de que numerosos estudios han investigado la estructura de comunidades y el comportamiento de forrajeo en roedores, aún existen grandes vacíos en nuestra comprensión de sus gremios tróficos. Nuestro objetivo fue investigar las dietas de siete especies de pequeños (de roedores capturados entre el 2009 y el 2012. Datos de frecuencia para cuatro categorías de dieta indicaron que las siete especies de roedores consumieron cuatro categorías de dieta: artrópodos (88%), pedazos de hojas y fibras de plantas (61%), semillas intactas (con o sin pulpa de frutos; 50%), y esporas de micorrizas (45%). Omnivoría fue la estrategia utilizada por todas las especies, aunque el análisis con tablas de contingencia reveló diferencias significativas entre y dentro de especies en categorías de dieta. El análisis de agrupación presentó 2 grupos principales: el grupo Thomasomys spp. y Calomys sorellus , que incluye una gran proporción de semillas intactas, y partes de plantas en las muestras fecales y el grupo que incluye los géneros Akodon , Microryzomys y Oligoryzomys , el cual incluyó una proporción mayor de artrópodos en sus muestras fecales, pero con niveles altos de semillas intactas. Semillas intactas de al menos 17 especies de plantas (9 familias) fueron encontradas en las muestras fecales. Concluimos que este ensamble de roedores sigmodontinos es omnívoro y que probablemente las especies

  17. Seroprevalencia de hantavirus en roedores y casos humanos en el sur de la Argentina Hantavirus seroprevalence in rodents and human cases in southern Argentina

    Directory of Open Access Journals (Sweden)

    Edmundo Larrieu

    2003-04-01

    longicaudatus and in human beings, demonstrating mainly transmission from rodents to human and the possibility of person-to-person transmission. The goal of this paper is to present new information on hantavirus rodent carrier species in Argentina, the prevalence of antibodies to hantavirus (1999-2001 period and the relationship of the rodent population size and seroprevalence with the occurrence of human cases (1996-2001 period. To this end, a total of 3,973 Sherman type traps for capturing live rodents were placed in six campaigns from October 1999 to May 2001. Rodent blood samples were obtained and processed by means of enzymoimmunoassay with antigens developed from the Andes virus. A summary of results indicates 397 captured rodents, with a 10% trapping success rate and a 1.0% prevalence of antibodies to hantavirus. Considerable differences were observed in species captured in each region. Seropositive O. longicaudatus and A. olivaceus specimens, as well as potential hantavirus O. flavescens and C. laucha carriers, were captured. Six human cases were recorded during the 1993-1995 period (corresponding to retrospective studies, while 21 cases were reported in 1996-1998 and 6 in 1999-2001. The correlation between occurrence of human cases, seroprevalence in rodents and trapping success is analyzed.

  18. Helminth Infections of Rodents and Their Zoonotic Importance in Boyer-Ahmad District, Southwestern Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Javad RANJBAR

    2017-12-01

    Full Text Available AbstractBackground: Rodents are considered as reservoirs of various zoonotic diseases including helminthic infections. The current study aimed to evaluate the prevalence of helminth infections in rodents, in Boyer-Ahmad district, Southwestern Iran.Methods: Overall, 52 rodents were captured from various areas of the district by Sherman live traps. The animals were then euthanized and dissected. During necropsy, each organ was examined macroscopically for presence of any cyst or visible parasite. The gastrointestinal tract was removed and their contents were evaluated for larva or adult worms. Trichinella larvae in the rodents’ muscles were investigated by both digestion and pathological methods.Results: Twenty-eight (53.8% of the trapped rodents were male. The rodents were including 25 (48.1% Meriones persicus, 1(1.9% Calomyscus bailwardi, 1 (1.9% Arvicola terresterris, 7 (13.5% Rattus rattus, 8 (15.4% R. norvegicus, and 10 (19.2% Apodemus sylvaticus. Of them, 38 (73.0% were infected with at least one helminth. Collected rodents were infected with Hymenolepis diminuta (50%, Hymenolepis nana fraterna (28.8%, Skrjabinotaenia sp. (15.4%, Anoplocephalidae sp. (15.4%, Cysticercus fasciolaris (5.8%, Trichuris muris (36.5%, Aspiculuris tetraptera (15.4%, Syphacia sp. (5.7%, Rictularia sp. (15.4%, Trichostrongylus sp. (3.8%, and Gongylonema sp. (3.8%. M. persicus was the most (84% infected rodent, yet the differences between rodent genus and helminth infectivity were not statistically significant (P>0.05.Conclusion: The rodents in Boyer-Ahmad district are infected with different helminths infections that some of them are recognized as threat to human health.

  19. Activity of nucleic acid polymers in rodent models of HBV infection.

    Science.gov (United States)

    Schöneweis, Katrin; Motter, Neil; Roppert, Pia L; Lu, Mengji; Wang, Baoju; Roehl, Ingo; Glebe, Dieter; Yang, Dongliang; Morrey, John D; Roggendorf, Michael; Vaillant, Andrew

    2018-01-01

    Nucleic acid polymers (NAPs) block the release of HBsAg from infected hepatocytes. These compounds have been previously shown to have the unique ability to eliminate serum surface antigen in DHBV-infected Pekin ducks and achieve multilog reduction of HBsAg or HBsAg loss in patients with chronic HBV infection and HBV/HDV coinfection. In ducks and humans, the blockage of HBsAg release by NAPs occurs by the selective targeting of the assembly and/or secretion of subviral particles (SVPs). The clinically active NAP species REP 2055 and REP 2139 were investigated in other relevant animal models of HBV infection including woodchucks chronically infected with WHV, HBV transgenic mice and HBV infected SCID-Hu mice. The liver accumulation of REP 2139 in woodchucks following subcutaneous administration was examined and was found to be similar to that observed in mice and ducks. However, in woodchucks, NAP treatment was associated with only mild (36-79% relative to baseline) reductions in WHsAg (4/10 animals) after 3-5 weeks of treatment without changes in serum WHV DNA. In HBV infected SCID-Hu mice, REP 2055 treatment was not associated with any reduction of HBsAg, HBeAg or HBV DNA in the serum after 28 days of treatment. In HBV transgenic mice, no reductions in serum HBsAg were observed with REP 2139 with up to 12 weeks of treatment. In conclusion, the antiviral effects of NAPs in DHBV infected ducks and patients with chronic HBV infection were weak or absent in woodchuck and mouse models despite similar liver accumulation of NAPs in all these species, suggesting that the mechanisms of SVP assembly and or secretion present in rodent models differs from that in DHBV and chronic HBV infections. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Evaluating nest supplementation as a recovery strategy for the endangered rodents of the Florida Keys

    Science.gov (United States)

    Cove, Michael V.; Simons, Theodore R.; Gardner, Beth; Maurer, Andrew S.; O'Connell, Allan F.

    2017-01-01

    The Key Largo woodrat (Neotoma floridana smalli) and Key Largo cotton mouse (Peromyscus gossypinus allapaticola) are federally endangered subspecies endemic to the tropical hardwood hammocks of Key Largo, Florida. Woodrats are considered generalists in habitat and diet, yet a steady decline in natural stick nests and capture rates over the past several decades suggests that they are limited by the availability of nesting habitat due to habitat loss and fragmentation. The more specialized Key Largo cotton mouse appears to rely on old growth hammock, a habitat type that is rare following past land clearing. In 2004, the U.S. Fish and Wildlife Service started building supplemental nest structures to restore habitat quality and connectivity for these endangered rodents, but nest use requires evaluation. We used camera traps and occupancy models to evaluate the factors influencing woodrat and cotton mouse use of the supplemental nests. We detected woodrats at 65 and cotton mice at 175 of 284 sampled nest structures, with co-occurrence at 38 nests. Woodrat nest use followed a gradient from low nest use in the north to high nest use in the south, which might relate to the proximity of free-ranging domestic cat (Felis catus) colonies in residential developments. Cotton mouse nest use, however, was related positively to mature hammock and related negatively to disturbed areas (e.g. scarified lands). The two species occurred independently of each other. Stick-stacking behavior was observed at supplemental nests and, although it was correlated with detection of woodrats, it was not a strong predictor of their occu