Sample records for spixii rodentia caviomorpha

  1. Chorioallantoic placentation in Galea spixii (Rodentia, Caviomorpha, Caviidae)

    PubMed Central

    Oliveira, Moacir F; Mess, Andrea; Ambrósio, Carlos E; Dantas, Carlos AG; Favaron, Phelipe O; Miglino, Maria A

    2008-01-01

    Background Placentas of guinea pig-related rodents are appropriate animal models for human placentation because of their striking similarities to those of humans. To optimize the pool of potential models in this context, it is essential to identify the occurrence of characters in close relatives. Methods In this study we first analyzed chorioallantoic placentation in the prea, Galea spixii, as one of the guinea pig's closest relatives. Material was collected from a breeding group at the University of Mossoró, Brazil, including 18 individuals covering an ontogenetic sequence from initial pregnancy to term. Placentas were investigated by means of histology, electron microscopy, immunohistochemistry (vimentin, ?-smooth muscle actin, cytokeration) and proliferation activity (PCNA). Results Placentation in Galea is primarily characterized by an apparent regionalization into labyrinth, trophospongium and subplacenta. It also has associated growing processes with clusters of proliferating trophoblast cells at the placental margin, internally directed projections and a second centre of proliferation in the labyrinth. Finally, the subplacenta, which is temporarily supplied in parallel by the maternal and fetal blood systems, served as the center of origin for trophoblast invasion. Conclusion Placentation in Galea reveals major parallels to the guinea pig and other caviomorphs with respect to the regionalization of the placenta, the associated growing processes, as well as trophoblast invasion. A principal difference compared to the guinea pig occurred in the blood supply of the subplacenta. Characteristics of the invasion and expanding processes indicate that Galea may serve as an additional animal model that is much smaller than the guinea pig and where the subplacenta partly has access to both maternal and fetal blood systems. PMID:18771596

  2. Development of the inverted visceral yolk sac in three species of caviids (Rodentia, Caviomorpha, Caviidae).

    PubMed

    Miglino, M A; Franciolli, A L R; de Oliveira, M F; Ambrósio, C E; Bonatelli, M; Machado, M R F; Mess, A

    2008-08-01

    Guinea pig related rodents possess numerous derived placental characters. We attempt to identify diversity within the visceral yolk sac and its association with the chorioallantoic placenta in three species of caviids, two of them possessing a capsule formed by the decidua that covers the chorioallantoic placenta. The results verify that in early pregnancy all three species have an inverted yolk sac placenta. In advanced pregnancy the species differ: Galea spixii, as representative without a capsule, bear a yolk sac in apposition to the chorioallantoic placenta with signs of exchange activity until term. Galea is similar to other caviomorphs in this respect. In Dasyprocta leporina and Cuniculus paca, the representatives possessing a capsule, the yolk sac endoderm lacks signs of substance exchange. Evidently, the presence of a capsule prevents such an interaction. The variations established here must be considered if animal models for human placentation are required which have restricted access to the chorioallantoic placenta from the outside. PMID:18586321

  3. Development of the Inverted Visceral Yolk Sac in Three Species of Caviids (Rodentia, Caviomorpha, Caviidae)

    Microsoft Academic Search

    M. A. Miglino; A. L. R. Franciolli; M. F. de Oliveira; C. E. Ambrósio; M. Bonatelli; M. R. F. Machado; A. Mess

    2008-01-01

    Guinea pig related rodents possess numerous derived placental characters. We attempt to identify diversity within the visceral yolk sac and its association with the chorioallantoic placenta in three species of caviids, two of them possessing a capsule formed by the decidua that covers the chorioallantoic placenta. The results verify that in early pregnancy all three species have an inverted yolk

  4. Functional anatomy of the limbs of erethizontidae (Rodentia, Caviomorpha): Indicators of locomotor behavior in Miocene porcupines.

    PubMed

    Candela, Adriana M; Picasso, Mariana B J

    2008-05-01

    Functional analysis of the limb bones of the erethizontid Steiromys duplicatus, one of the most abundant Miocene porcupines from Patagonia, provides evidence to infer their locomotor behavior. Remains of the giant Neosteiromys pattoni (Late Miocene of Northeast Argentina) are also analyzed. Osteological and myological features of extant porcupines were evaluated and used as a model to interpret the functional significance of Miocene species' limbs. Several features in erethizontids are compatible with the ability to climb: the low humeral tuberosities indicate a mobile gleno-humeral joint; the prominent and distally extended deltopectoral crest indicates a powerful pectoral muscle, which is particularly active when climbing; the humero-ulnar and humero-radial joints are indicative of pronation-supination movements; the well-developed lateral epicondylar ridge and the medially protruding entepicondyle are in agreement with an important development of the brachioradialis, supinator, flexor digitorum profundus, and pronator teres muscles, acting in climbing and grasping functions; the mechanical advantage of the biceps brachii would be emphasized because of its distal attachment on the bicipital tuberosity. As with extant porcupines, in Miocene species, the large femoral head would have permitted a broad range of abduction of the femur, and the medially protruding lesser trochanter would have emphasized the abduction and outward rotation of the femur by the action of the ilio-psoas complex. In S. duplicatus, the shape of the hip, knee, and cruro-astragalar, calcaneo-astragalar, and astragalo-navicular joints would have allowed lateral and rotational movements, although probably to a lesser degree than in extant porcupines. Foot features of S. duplicatus (e.g., great medial sesamoid bone, medial astragalar head, complete hallux) indicate that this species would have had grasping ability, but would not have achieved the high degree of specialization of Coendou. Steiromys duplicatus would have been a semiarboreal dweller, resembling Erethizon dorsatum. PMID:18157864

  5. Feeding and digesting fiber and tannins by an herbivorous rodent, Octodon degus (Rodentia:Caviomorpha).

    PubMed

    Bozinovic, F; Novoa, F F; Sabat, P

    1997-11-01

    Differences in feeding rates and digestive efficiency of alternative experimental diets differing in cellulose or fiber and a secondary metabolite (the hydrolyzable tannin, tannic acid [TA]) were assessed with the herbivorous burrowing caviomorph rodent Octodon degus (degu). Degus live in open scrub subjected to summer droughts. The in vitro activity of the digestive enzyme sucrase was not significantly different between treatments with high and low TA. Analysis of the whole organism allowed us to conclude that in vitro analyses of enzymatic digestive activity and plant defenses cannot be used to explain and fully understand the physiological and behavioral effects of plant defenses on mammalian herbivores. We observed no body mass reduction due to effects of dietary treatments. O. degus seemed to compensate for nutritionally poor food by increasing gut content volume. We conclude that fiber and secondary compounds may influence feeding and digestive strategies and vice versa. PMID:9406439

  6. Hematologic and plasma biochemical values of Spix's macaws (Cyanopsitta spixii).

    PubMed

    Foldenauer, Ulrike; Borjal, Raffy Jim; Deb, Amrita; Arif, Abdi; Taha, Abid Sharif; Watson, Ryan William; Steinmetz, Hanspeter; Bürkle, Marcellus; Hammer, Sven

    2007-12-01

    The Spix's macaw (Cyanopsitta spixii) is considered the world's most endangered parrot, with the last wild bird disappearing in 2001 and only 74 birds in captivity. To establish hematologic and plasma biochemical reference ranges and to look for differences relative to sex, age, and season, we obtained blood samples from 46 captive Spix's macaws (23 male, 23 female) housed in aviaries at the Al Wabra Wildlife Preservation in the State of Qatar. No significant differences in hematologic or plasma biochemical values were found between females and males. Adult and juvenile birds differed in mean concentrations of glucose, total protein, amylase, cholesterol, and phosphorus; in percentages of heterophils and lymphocytes; and in the absolute lymphocyte count. Total protein, cholesterol, and phosphorus concentrations; hematocrit; and heterophil and lymphocyte counts differed significantly by season. Baseline hematologic and plasma biochemical ranges were established, which may be useful as reference values for clinicians working with this highly endangered species. PMID:18351006

  7. Chromosomal evolution in Rodentia

    PubMed Central

    Romanenko, S A; Perelman, P L; Trifonov, V A; Graphodatsky, A S

    2012-01-01

    Rodentia is the most species-rich mammalian order and includes several important laboratory model species. The amount of new information on karyotypic and phylogenetic relations within and among rodent taxa is rapidly increasing, but a synthesis of these data is currently lacking. Here, we have integrated information drawn from conventional banding studies, recent comparative painting investigations and molecular phylogenetic reconstructions of different rodent taxa. This permitted a revision of several ancestral karyotypic reconstructions, and a more accurate depiction of rodent chromosomal evolution. PMID:22086076

  8. A longitudinal study on avian polyomavirus-specific antibodies in captive Spix's macaws (Cyanopsitta spixii).

    PubMed

    Deb, Amrita; Foldenauer, Ulrike; Borjal, Raffy Jim; Streich, W Jürgen; Lüken, Caroline; Johne, Reimar; Müller, Hermann; Hammer, Sven

    2010-09-01

    Avian polyomavirus (APV) causes a range of disease syndromes in psittacine birds, from acute fatal disease to subclinical infections, depending on age, species, and other unidentified risk factors. To determine the prevalence of APV-specific antibodies in a captive population of Spix's macaws (Cyanopsitta spixii) in Quatar, 54 birds were tested by blocking enzyme-linked immunosorbent assay. A prevalence of 48.1% for APV antibodies, which indicates viral exposure, was found. Of 36 Spix's macaws that were serially tested over a period of 4 years, 50.0% were consistently positive, 36.1% were consistently negative, 5.5% had permanently declining antibody levels, and 2.8% showed variable results. By using polymerase chain reaction testing on whole blood samples, an apparent viremia was detected in 1 of 44 birds (2.3%), although contamination provides a likely explanation for this isolated positive result in a hand-reared chick. The white blood cell count was significantly higher in antibody-positive birds compared with antibody-negative birds (P < .05). Because antibody-positive and antibody-negative birds were housed together without a change in their respective antibody status, transmission of APV within the adult breeding population appeared to be a rare event. PMID:21046939

  9. Analysis of the genetic variability in a sample of the remaining group of Spix's Macaw ( Cyanopsitta spixii, Psittaciformes: Aves) by DNA fingerprinting

    Microsoft Academic Search

    Renato Caparroz; Cristina Y. Miyaki; Maria I. Bampi; Anita Wajntal

    2001-01-01

    The Spix's Macaw Cyanopsitta spixii is the world's most endangered parrot. There is only one male in the wild and 39 birds maintained in captivity. Among these, only nine were originally from the wild. The genetic variability of seven captive birds (six originally from the wild) was estimated using Jeffreys' human minisatellite probes 33.15 and 33.6. The similarity indexes obtained

  10. Molecular Phylogeny of Rodentia, Lagomorpha, Primates, Artiodactyla, and Carnivora and Molecular Clocks

    Microsoft Academic Search

    Wen-Hsiung Li; Manolo Gouy; Paul M. Sharp; Colm O'Huigin; Yau-Wen Yang

    1990-01-01

    Phylogenetic analysis of DNA sequences from primates, rodents, lagomorphs, artiodactyls, carnivores, and birds strongly suggests that the order Rodentia is an outgroup to the other four mammalian orders and that Artiodactyla and Carnivora belong to a superordinal clade. Further, there is strong evidence against the Glires concept, which unites Lagomorpha and Rodentia. The radiation among Lagomorpha, Primates, and Artiodactyla-Carnivora is

  11. Complete mitochondrial genome sequence of Marmota himalayana (Rodentia: Sciuridae) and phylogenetic analysis within Rodentia.

    PubMed

    Chao, Q J; Li, Y D; Geng, X X; Zhang, L; Dai, X; Zhang, X; Li, J; Zhang, H J

    2014-01-01

    This is the first report of a complete mitochondrial genome sequence from Himalayan marmot (Marmota himalayana, class Marmota). We determined the M. himalayana mitochondrial (mt) genome sequence by using long-PCR methods and a primer-walking sequencing strategy with genus-specific primers. The complete mt genome of M. himalayana was 16,443 bp in length and comprised 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a typical control region (CR). Gene order and orientation were identical to those in mt genomes of most vertebrates. The heavy strand showed an overall A+T content of 63.49%. AT and GC skews for the mt genome of the M. himalayana were 0.012 and -0.300, respectively, indicating a nucleotide bias against T and G. The control region was 997 bp in size and displayed some unusual features, including absence of repeated motifs and two conserved sequence blocks (CSB2 and CSB3), which is consistent with observations from two other rodent species, Sciurus vulgaris and Myoxus glis. Phylogenetic analysis of complete mt DNA sequences without the control region including 30 taxa of Rodentia was performed with Maximum-Likelihood (ML) and Bayesian Inference (BI) methods and provided strong support for Sciurognathi polyphyly and Hystricognathi monophyly. This analysis also provided evidence that M. himalayana mt DNA was closely related to that from Sciurus vulgaris (Sciuridae) and was similar to mt DNA from Myoxus glis. PMID:24782088

  12. DNA barcoding of Murinae (Rodentia: Muridae) and Arvicolinae (Rodentia: Cricetidae) distributed in China.

    PubMed

    Li, Jing; Zheng, Xin; Cai, Yansen; Zhang, Xiuyue; Yang, Min; Yue, Bisong; Li, Jing

    2015-01-01

    Identification of rodents is very difficult mainly due to high similarities in morphology and controversial taxonomy. In this study, mitochondrial cytochrome oxidase subunit I (COI) was used as DNA barcode to identify the Murinae and Arvicolinae species distributed in China and to facilitate the systematics studies of Rodentia. In total, 242 sequences (31 species, 11 genera) from Murinae and 130 sequences (23 species, 6 genera) from Arvicolinae were investigated, of which 90 individuals were novel. Genetic distance, threshold method, tree-based method, online BLAST and BLOG were employed to analyse the data sets. There was no obvious barcode gap. The average K2P distance within species and genera was 2.10% and 12.61% in Murinae, and 2.86% and 11.80% in Arvicolinae, respectively. The optimal threshold was 5.62% for Murinae and 3.34% for Arvicolinae. All phylogenetic trees exhibited similar topology and could distinguish 90.32% of surveyed species in Murinae and 82.60% in Arvicolinae with high support values. BLAST analyses yielded similar results with identification success rates of 92.15% and 93.85% for Murinae and Arvicolinae, respectively. BLOG successfully authenticated 100% of detected species except Leopoldamys edwardsi based on the latest taxonomic revision. Our results support the species status of recently recognized Micromys erythrotis, Eothenomys tarquinius and E. hintoni and confirm the important roles of comprehensive taxonomy and accurate morphological identification in DNA barcoding studies. We believe that, when proper analytic methods are applied or combined, DNA barcoding could serve as an accurate and effective species identification approach for Murinae and Arvicolinae based on a proper taxonomic framework. PMID:24838015

  13. Topografia do cone medular no ratão-do-banhado ( Myocastor coypus Molina, 1782 - Rodentia: Mammalia)

    Microsoft Academic Search

    Gilberto Valente Machado; Josy Alvarenga Cal; Arlei José Birck

    Topography of the medullar cone in nutria (Myocastor coypus Molina, 1782 - Rodentia: Mammalia). Aiming to investigate the topography of the medullar cone, ten adult nutria (Myocastor coypus), eight male and two female, were previously fixed in 10% aqueous formalin solution, maintained in similar solution and dissected. After the dissection the following data were noted: a) the medullar cone apex

  14. FOSSIL RECORD OF THE ANDEAN RAT, Andinomys edax (RODENTIA: CRICETIDAE), IN ARGENTINA

    Microsoft Academic Search

    Pablo E. Ortiz; J. Pablo Jayat

    Andinomys edax (Rodentia, Cricetidae) has a broad distribution in the Central Andean region. The fossil record is restricted to only three localities from Lower-Middle Pleistocene in Bolivia to Upper Holocene in Argentina. Recent field work in northwestern Argentina produced five new paleontological localities: Las Juntas, Catamarca (13.4 - 12.95 kyr BP); Inca Cueva 4, Jujuy (11 - 9 kyr BP);

  15. DNA extraction from bristles and quills of Chaetomys subspinosus (Rodentia: Erethizontidae) using a novel protocol

    Microsoft Academic Search

    C. G. Oliveira; R. A. Martinez; F. A. Gaiotto

    2007-01-01

    DNA extraction protocols are as varied as DNA sources. When it comes to endangered species, it is especially important to pay attention to all details that ensure the completion of the study goals and effectiveness in attaining useful data for conserva- tion. Chaetomys subspinosus (Rodentia: Erethizontidae) is a secretive arboreal porcupine endemic to certain ecosystems of the Brazilian At- lantic

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

    PubMed

    Lessmann, Janeth; Arrivillaga, Jazzmín; Aguilera, Marisol

    2011-06-01

    Recent phylogenetic studies based on cytochrome b gene sequence, have determined that the species historically known as Sigmodon hispidus (Rodentia) from South America comprises a species S. hirsutus of paraphyletic origin. The aim of this study was to test the hypothesis that populations from Venezuela, represent the sensu strict form, ancestral haplotypes, and monophyletic subspecieS. For this, 12 individual sequences from three localities of different biogeographic regions in Venezuela were evaluated and sequenced based on cyto b. Additionally, the sequences were used to develop a cladistic analysis and genetic distance calculations, and to compare this information with two individual sequences of Sigmodon specimens available in Genbank. Phylogenetic analyses show that the three populations of S. hirsutus of Venezuela form an ancestral and monophyletic subclade supported by high bootstrap values and significant genetic distance between subclade within the S. hirsutus. Besides, the existence of two lineages suggests two subspecies, S. hirsutus hirsutus from Venezuela, and S. hirsutus mexicanus from Mexico-Central America, but, both species need formal description. PMID:21721239

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

    PubMed Central

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

    2012-01-01

    Abstract Karyotypes of Hapalomys delacouri (Rodentia, Muridae) and Typhlomys cinereus (Rodentia, Platacanthomyidae) from Vietnam are described for the first time. The diploid karyotype of Hapalomys delacouri is 38 (NFa=48), consisting of six pairs of bi-armed and 12 pairs of acrocentric autosomes decreasing in size; plus a large metacentric X chromosome and Y chromosome, also metacentric, that is equal in size to the largest pair of acrocentric autosomes. The newly described karyotype differs significantly from that reported for Hapalomys delacouri from northern Thailand. The latter record very likely represents a different species of Hapalomys, possibly the taxon Hapalomys pasquieri described from north-central Laos.The diploid karyotype of Typhlomys cinereus is 38 (NF=48), consisting of five pairs of meta- to submetacentric and 14 pairs of acrocentric chromosomes varying in size from large to small; sex chromosomes were not defined. PMID:22328851

  18. MICROMAMÍFEROS (DIDELPHIMORPHIA Y RODENTIA) DEL PARQUE NACIONAL LIHUÉ CALEL, LA PAMPA, ARGENTINA

    Microsoft Academic Search

    Pablo Tet; Javier A. Pereira; Natalia G. Fracassi; Silvina B. C. Bisceglia; Sofía Heinonen Fortabat

    2009-01-01

    Small mammals (Didelphimorphia and Rodentia) from Parque Nacional Lihue Calel, La Pampa Province, Argentina. We studied the terrestrial small mammal (<500 g) assemblage from Parque Nacional Lihué Calel (37°57'S, 65°33'O, La Pampa Province, Argentina) in 1993 and 2003-2006. Information about habitat, ecology, reproduc- tion, and population structure is provided for the didelphid marsupials Lestodelphys halli and Thylamys pallidior, the cricetid

  19. Characterization of the satellite DNA Msat-160 from species of Terricola ( Microtus ) and Arvicola (Rodentia, Arvicolinae)

    Microsoft Academic Search

    Manuel J. Acosta; Juan A. Marchal; Cecilia Fernández-Espartero; Ismael Romero-Fernández; Michail T. Rovatsos; Eva B. Giagia-Athanasopoulou; Ekaterina Gornung; Riccardo Castiglia; Antonio Sánchez

    2010-01-01

    In the subfamily Arvicolinae (Cricetidae, Rodentia) the satellite DNA Msat-160 has been so far described in only some species\\u000a from the genus Microtus and in one species from another genus, Chionomys nivalis. Here we cloned and characterized this satellite in two new arvicoline species, Microtus (Terricola) savii and Arvicola amphibius (terrestris). We have also demonstrated, by PCR and FISH, its

  20. Molecular phylogeny and taxonomic reconsideration of the subfamily Zapodinae (Rodentia: Dipodidae), with an emphasis on Chinese species

    Microsoft Academic Search

    Zhenxin Fan; Shaoying Liu; Yang Liu; Bo Zeng; Xiuyue Zhang; Cong Guo; Bisong Yue

    2009-01-01

    Although the subfamily Zapodinae (Rodentia, Dipodidae) contains only five species, the phylogeny and taxonomy of these species are still being disputed. First, whether Eozapus and Napaeozapus should be treated as independent genera or subgenera of Zapus has been argued for a long period. Second, the subspecific genetic differentiation of Chinese jumping mouse (Eozapus setchuanus) has not been studied in detail,

  1. Nuclear DNA phylogeny of the squirrels (Mammalia: Rodentia) and the evolution of arboreality from c-myc and RAG1

    E-print Network

    Steppan, Scott

    Nuclear DNA phylogeny of the squirrels (Mammalia: Rodentia) and the evolution of arboreality from c-myc nuclear genes (c-myc and RAG1) comprising approximately 4500 bp of data (most in exons) are applied squirrel lineages. C-myc indels corroborate the sequence-based topologies. The common ancestor of extant

  2. LA JAYUPA DE LA ALTURA (CUNICULUS TACZANOWSKII, RODENTIA, CUNICULIDAE), UN NUEVO REGISTRO DE MAMÍFERO PARA LA FAUNA DE BOLIVIA

    Microsoft Academic Search

    Boris Ríos-Uzeda; Robert B. Wallace; Julieta Vargas

    2004-01-01

    The mountain paca (Cuniculus taczanowskii, Rodentia, Cuniculidae): A new mammal record for Bolivia. In October 2002 we collected a specimen of the mountain paca (Cuniculus taczanowskii). This collection represents the first record of this species for Bolivia. In this note we describe the morphological characteristics that differentiate C. taczanowskii from C. paca, a more common species from the lowland forests

  3. A NEW GENUS AND SPECIES OF LUNGWORM (NEMATA: METASTRONGYLOIDEA) FROM AKODON MOLLIS THOMAS, 1894 (RODENTIA: CRICETIDAE) IN PERU.

    PubMed

    Morales, Maria E; Ubelaker, John E; Gardner, Scott L

    2011-12-16

    Abstract Akodonema luzsarmientae n.g. n.sp. (Nemata: Metastrongyloidea) is described from the pulmonary arteries and heart from several individuals of Akodon mollis "soft grass mouse" (Rodentia: Cricetidae) collected in the region of Ancash, Peru. The new genus and species is distinguished by having a dorsal ray consisting of only two small widely separated papillae. PMID:22176066

  4. A NEW GENUS AND SPECIES OF LUNGWORM (NEMATA: METASTRONGYLOIDEA) FROM AKODON MOLLIS THOMAS, 1894 (RODENTIA: CRICETIDAE) IN PERU.

    PubMed

    Morales, Maria E; Ubelaker, John E; Gardner, Scott L

    2011-12-01

    Abstract Akodonema luzsarmientae n.g. n.sp. (Nemata: Metastrongyloidea) is described from the pulmonary arteries and heart from several individuals of Akodon mollis "soft grass mouse" (Rodentia: Cricetidae) collected in the region of Ancash, Peru. The new genus and species is distinguished by having a dorsal ray consisting of only two small widely separated papillae. PMID:22142432

  5. A new Eimeria species (Apicomplexa: Eimeriidae) infecting Onychomys species (Rodentia: Muridae) in New Mexico and Arizona.

    PubMed

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

    1998-12-01

    Fecal samples from 3 species of Onychomys (Rodentia: Muridae) captured in New Mexico and Arizona were examined for coccidia. Six of the 59 (10%) were infected with a new species of Eimeria. Sporulated oocysts (n = 105) of this new species are subspheroidal, 17.4 x 16.1 (14-21 x 13-19) microm, with ellipsoidal sporocysts 10.4 x 5.7 (9-12 x 5-8) microm. This species occurred in 3 of 24 (13%) Onychomys arenicola, 2 of 31 (6%) Onychomys leucogaster from New Mexico, and 1 of 4 (25%) Onychomys torridus from Arizona. Isolates recovered from O. leucogaster and O. torridus were inoculated into O. leucogaster (n = 5) and produced infections with a prepatent period of 7 days and a patent period of 7-23 days. PMID:9920315

  6. Diversification and biogeography of the Neotropical caviomorph lineage Octodontoidea (Rodentia: Hystricognathi).

    PubMed

    Upham, Nathan S; Patterson, Bruce D

    2012-05-01

    The rodent superfamily Octodontoidea comprises 6 families, 38 genera, and 193 living species of spiny rats, tuco-tucos, degus, hutias, and their relatives. All are endemic to the Neotropical Region where they represent roughly three-quarters of extant caviomorphs. Although caviomorph monophyly is well established and phylogenetic hypotheses exist for several families, understanding of octodontoid relationships is clouded by sparse taxon sampling and single-gene analyses. We examined sequence variation in one mitochondrial (12S rRNA) and three nuclear genes (vWF, GHR, and RAG1) across all caviomorph families (including 47 octodontoid species), all phiomorph families, and the sole remaining hystricognath family, using the gundi (Ctenodactylus) and springhaas (Pedetes) as outgroups. Our analyses support the monophyly of Phiomorpha, Caviomorpha, and the caviomorph superfamilies Cavioidea (Dasyproctidae, Cuniculidae, and Caviidae, the latter including Hydrochoerus), Erethizontoidea, Chinchilloidea (including Dinomyidae), and Octodontoidea. Cavioids and erethizontoids are strongly supported as sisters, whereas chinchilloids appear to be sister to octodontoids. Among octodontoids, Abrocomidae is consistently recovered as the basal element, sister to a pair of strongly supported clades; one includes Octodontidae and Ctenomyidae as reciprocally monophyletic lineages, whereas the other includes taxa currently allocated to Echimyidae, Capromyidae and Myocastoridae. Capromys appears near the base of this clade, in keeping with current classification, but Myocastor is nested securely inside a clade of Echimyidae that also contains eumysopines, echimyines and dactylomyines. Another, more weakly supported clade of Echimyidae contains fossorial and scansorial taxa from the Chaco-Cerrado-Caatinga and the Atlantic Forest. Biogeographic analyses robustly recover the Patagonia-Southern Andes complex as ancestral for the Octodontoidea, with three component lineages emerging by the Oligocene-Miocene boundary (?23Ma): (1) stem abrocomids in the Central and Southern Andes; (2) a lineage leading to octodontids plus ctenomyids in Patagonia, later dispersing into the Chaco-Cerrado-Caatinga; and (3) a lineage leading to echimyids, capromyids, and myocastorids that subsequently radiated in more mesic biomes, including Amazonia, Atlantic Forest, and the Antilles. This reconstruction refutes earlier ideas that the diverse, generalized, mainly lowland family Echimyidae, which appears early in the fossil record, gave rise to the Andean lineages of octodontoids-instead, the reverse derivation appears to be true. We recommend formal synonymy of Myocastoridae with Echimyidae but defer a similar treatment of Capromyidae until additional hutia taxa and sequences can be analyzed. PMID:22327013

  7. Mites of the subgenus Neotomobia n. subg. (Acariformes: Myobiidae: Radfordia), parasites of the subfamily Neotominae (Rodentia: Cricetidae).

    PubMed

    Bochkov, Andre V; Guzmán-Cornejo, Carmen

    2014-10-01

    A new subgenus Neotomobia n. subg. (Acariformes: Myobiidae: Radfordia) is established for species parasitising rodents of the subfamily Neotominae (Rodentia: Cricetidae): Radfordia subuliger Ewing, 1938 (type-species), Radfordia eremici Fain & Bochkov, 2002, Radfordia neotomae Jameson & Whitaker, 1975 and Radfordia hamiltoni Jameson & Whitaker, 1975. Three new species are described: Radfordia peromyscus n. sp. from Peromyscus megalops Merriam from Mexico, Radfordia onychomys n. sp. from Onychomys leucogaster (Wied-Neuwied) from the USA and Radfordia megadontomys n. sp. from Megadontomys thomasi (Merriam) from Mexico. PMID:25204596

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

    PubMed

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

    2009-01-01

    Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of paternal care. In captivity, males of Volcano Mouse (Neotomodon alstoni) provide pups the same care provided by the mother, with the exception of suckling. Here we measured plasmatic testosterone concentrations 10 days after mating, five and 20 days postpartum, and 10 days after males were isolated from their families in order to determine possible changes in this hormone, associated to the presence and age of pups. Males of Volcano Mouse exhibited paternal behavior when their testosterone levels were relatively high. Although levels of this hormone did not change with the presence or pups age, males that invested more time in huddling showed higher testosterone levels. It is possible that in the Volcano Mouse testosterone modulates paternal behavior indirectly, as in the California mouse. PMID:19637720

  9. Hidden heterochromatin: Characterization in the Rodentia species Cricetus cricetus, Peromyscus eremicus (Cricetidae) and Praomys tullbergi (Muridae)

    PubMed Central

    2009-01-01

    The use of in situ restriction endonuclease (RE) (which cleaves DNA at specific sequences) digestion has proven to be a useful technique in improving the dissection of constitutive heterochromatin (CH), and in the understanding of the CH evolution in different genomes. In the present work we describe in detail the CH of the three Rodentia species, Cricetus cricetus, Peromyscus eremicus (family Cricetidae) and Praomys tullbergi (family Muridae) using a panel of seven REs followed by C-banding. Comparison of the amount, distribution and molecular nature of C-positive heterochromatin revealed molecular heterogeneity in the heterochromatin of the three species. The large number of subclasses of CH identified in Praomys tullbergi chromosomes indicated that the karyotype of this species is the more derived when compared with the other two genomes analyzed, probably originated by a great number of complex chromosomal rearrangements. The high level of sequence heterogeneity identified in the CH of the three genomes suggests the coexistence of different satellite DNA families, or variants of these families in these genomes. PMID:21637647

  10. DNA extraction from bristles and quills of Chaetomys subspinosus (Rodentia: Erethizontidae) using a novel protocol.

    PubMed

    Oliveira, C G; Martinez, R A; Gaiotto, F A

    2007-01-01

    DNA extraction protocols are as varied as DNA sources. When it comes to endangered species, it is especially important to pay attention to all details that ensure the completion of the study goals and effectiveness in attaining useful data for conservation. Chaetomys subspinosus (Rodentia: Erethizontidae) is a secretive arboreal porcupine endemic to certain ecosystems of the Brazilian Atlantic Forest. A multidisciplinary study (including genetic data) was performed to create a management plan for the conservation of this species. Individuals from natural populations of the states of Bahia, Espírito Santo and Sergipe were sampled. To obtain a reliable and abundant amount of starting material, non-destructive methods were tested, extracting DNA from the bristles and quills that comprise most of this animal's hide. This method has also been innovative in adapting a DNA extraction protocol traditionally used for plants. Digestion using proteinase K was followed by protein precipitation with CTAB, a chloroform-isoamyl alcohol cleaning and DNA precipitation with isopropyl alcohol. This protocol supplies good-quality DNA for genetic analysis with molecular markers based on PCR. PMID:18050086

  11. A new species of porcupine, genus Coendou (Rodentia: Erethizontidae) from the Atlantic forest of northeastern Brazil.

    PubMed

    Pontes, Antonio Rossano Mendes; Gadelha, José Ramon; Melo, Éverton R A; de Sá, Fabrício Bezerra; Loss, Ana Carolina; Caldara Junior, Vilacio; Costa, Leonora Pires; Leite, Yuri L R

    2013-01-01

    We report the discovery of a new species of Coendou (Rodentia, Erethizontidae), here designated Coendou speratus sp. nov. This small porcupine, locally known as coandumirim, is found in the Pernambuco Endemism Centre in the Atlantic coast of northeastern Brazil north of the São Francisco river, one of the most important known biodiversity hotspots. The geographic range of C. speratus overlaps with that of the larger, widespread C. prehensilis, but not with that of C. insidiosus from the southeastern Atlantic forest, nor with that of C. nycthemera, an eastern Amazonian species. Coendou speratus is a small-bodied, long-tailed species that appears to be completely spiny because it lacks long dorsal fur. The dorsal quills have conspicuously brownish red tips that contrast with the blackish dorsal background color. The new species is overall similar to C. nycthemera, but the dorsal body quills are typically tricolored in the former and bicolored in the latter. The new species is externally very distinct from C. insidiosus, especially because the latter has bicolored dorsal quills that are almost completely hidden beneath longer and homogeneous pale or dark hairs. PMID:26042302

  12. Chromosomal characterization of Arvicanthis species (Rodentia, Murinae) from western and central Africa: implications for taxonomy.

    PubMed

    Volobouev, V T; Ducroz, J F; Aniskin, V M; Britton-Davidian, J; Castiglia, R; Dobigny, G; Granjon, L; Lombard, M; Corti, M; Sicard, B; Capanna, E

    2002-01-01

    A chromosome study of unstriped grass rats of the genus Arvicanthis (Rodentia, Murinae) in western and central Africa is presented. The observations extend the data available to 242 specimens from 59 localities. All individuals karyotyped belong to four karyotypic forms, or cytotypes, earlier described as ANI-1, ANI-2, ANI-3, and ANI-4 and are presumed to correspond to four distinct species. In order to provide diagnostic characters for these western and one central African Arvicanthis species, we standardized the chromosomal data available and developed a G- and C-banded chromosome nomenclature that allows easy species identification. Each form is characterized by a distinct geographical distribution, roughly following the biogeographical domains of western Africa, although their precise limits remain to be assessed. The sole area of sympatry detected is the region of the inner delta of the Niger River, where both ANI-1 and ANI-3 can be found. It is proposed that the three western African species ANI-1, ANI-3, and ANI-4 be renamed as A. niloticus, A. ansorgei, and A. rufinus, respectively. PMID:12438807

  13. New murid (Mammalia, Rodentia) fossils from a late Pliocene (2.4 Ma) locality, Hadar A.L. 894, Afar Region, Ethiopia

    Microsoft Academic Search

    Denné N. Reed

    2011-01-01

    This paper describes a new assemblage of fossil murids (Mammalia: Rodentia) from an Oldowan archeological site, Hadar, A.L. 894. The dates for the site are well constrained to between 2.35 and 2.9 Ma and the site itself has an estimated age of 2.4 Ma. The A.L. 894 assemblage is the first described from the younger Busidima Formation at Hadar and

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

    PubMed

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

    2014-10-01

    Despite the order Rodentia present worldwide distribution and large number of species in the Brazilian fauna, detailed studies on testicular morphophysiology are still scarce. Therefore, this study aimed to analyze the dynamics of the spermatogenic process of Oxymycterus nasutus using morphometrical and stereological tools. Testicles from ten sexually mature males were used, showing a gonadosomatic index of 0.89%. The testicular parenchyma showed one of the highest tubulesomatic indexes reported among wild rodents - 0.82% - from which 65.12% was allocated into seminiferous epithelium. The average tubular diameter was 249.89 ?m, whereas the epithelium height was 62.47 ?m and the total length was 18.62 m per gram of testis. Eight different stages of the seminiferous epithelium cycle were described. Stage 1 was used for counting the germ cell population as well as the Sertoli cells. On average, 3.47 type-A spermatogonia, 24.39 primary spermatocytes in preleptotene/leptotene, 24.13 primary spermatocytes in pachytene, 68.38 round spermatids and 7.33 Sertoli cells were found per tubular cross section. There were 91.02 × 10(6) Sertoli cells per gram of testis and each cell was able to support 9.33 spermatids and 16.43 germ cells. The coefficient of spermatogonial mitosis was 7.02, while 2.83 spermatids were produced for each primary spermatocyte in pachytene. The overall efficiency of spermatogenesis was 19.70 cells, whereas the sperm reserve per gram of testis totalized 849.63 × 10(6) spermatids. Therefore, the presented data showed that O. nasutus shows a high energetic investment in reproduction, corroborating the findings for other species of the Cricetidae family. PMID:25037444

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

    PubMed

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

    2015-08-01

    A new species of nematode, Squamasnema amazonica n. gen. n. sp., is described based on specimens found parasitizing the small intestine of Proechimys roberti (Rodentia: Echimyidae) collected during a survey of the fauna of Tapirapé-Aquirí National Forest (Brazil, Eastern Brazilian Amazon). The nematodes were fixed and processed for light microscopy and scanning electron microscopy (SEM). These nematodes were classified under the family Heligmonellidae and the subfamily Heligmonellinae. Although several species in the family Heligmonellidae exhibit discontinuous ridges, Squamasnema n. gen. and Trichotravassosia are the only genera with columns of scales along their entire body, as an apomorphy of the synlophe. Squamasnema n. gen. has columns of cuticular cells along its body, except for on the left flank, and exhibits a synlophe with no size gradient or inclination and does not present chitinized structures supporting the synlophe. Therefore, due to these morphological differences of Squamasnema n. gen., the creation of a new genus was necessary. PMID:25910627

  16. Molecular phylogeny and taxonomic reconsideration of the subfamily Zapodinae (Rodentia: Dipodidae), with an emphasis on Chinese species.

    PubMed

    Fan, Zhenxin; Liu, Shaoying; Liu, Yang; Zeng, Bo; Zhang, Xiuyue; Guo, Cong; Yue, Bisong

    2009-06-01

    Although the subfamily Zapodinae (Rodentia, Dipodidae) contains only five species, the phylogeny and taxonomy of these species are still being disputed. First, whether Eozapus and Napaeozapus should be treated as independent genera or subgenera of Zapus has been argued for a long period. Second, the subspecific genetic differentiation of Chinese jumping mouse (Eozapus setchuanus) has not been studied in detail, neither from morphological nor molecular aspects. In this study, the phylogenetic relationship among all the five species of Zapodinae was reconstructed using DNA sequence data from the mitochondrial cytochrome b gene and the nuclear interphotoreceptor retinoid binding protein gene. Bayesian inference, maximum parsimony and maximum likelihood analyses were conducted. The results showed that two major clades could be recognized within Zapodinae. Eozapus setchuanus, is the species endemic to China, strongly formed a monophyletic clade. In the other clade, genus Zapus received significant support in all analyses to be the sister group of the genus Napaeozapus. By comparing genetic distances among these three genera, we conclude that both Eozapus and Napaeozapus should be considered as valid genera rather than subgenera of Zapus. Furthermore, we observed that the two subspecies of E. setchuanus did not form reciprocally monophyletic groups, thus the traditional taxonomy which divided E. setchuanus into two subspecies based on only one morphological character was questionable. PMID:19303451

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

    PubMed Central

    2013-01-01

    We report the detection, isolation and description of Trypanosoma (Megatrypanum) lainsoni n. sp. from a caviomorph rodent, Mesomys hispidus (Rodentia: Echimyidae), obtained in the Rio Negro region of the state of Amazonas, in northern Brazil. Laboratory-bred white mice (Mus musculus) and rats (Rattus rattus) were inoculated with large numbers of culture forms by intraperitoneal route, and trypomastigotes appeared in their blood 3–8 days post-inoculation. One single epimastigote was also found in Mus musculus. Similar attempts to infect Rattus norvegicus, hamsters (Mesocricetus auratus), the opossum Didelphis marsupialis, the anteater Tamandua tetradactyla and triatomine bugs were unsuccessful, following six months of observations and microscopic examinations of blood films and blood cultures. As we have found no previous record of a Trypanosoma (Megatrypanum) species naturally infecting a member of the family Echimyidae, or any other caviomorph rodent, we conclude that this is the first time such an infection has been reported. The new species is unusual in the subgenus for its infectivity to laboratory mice. PMID:24309069

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

    PubMed

    Naiff, Roberto Daibes; Barrett, Toby Vincent

    2013-01-01

    We report the detection, isolation and description of Trypanosoma (Megatrypanum) lainsoni n. sp. from a caviomorph rodent, Mesomys hispidus (Rodentia: Echimyidae), obtained in the Rio Negro region of the state of Amazonas, in northern Brazil. Laboratory-bred white mice (Mus musculus) and rats (Rattus rattus) were inoculated with large numbers of culture forms by intraperitoneal route, and trypomastigotes appeared in their blood 3-8 days post-inoculation. One single epimastigote was also found in Mus musculus. Similar attempts to infect Rattus norvegicus, hamsters (Mesocricetus auratus), the opossum Didelphis marsupialis, the anteater Tamandua tetradactyla and triatomine bugs were unsuccessful, following six months of observations and microscopic examinations of blood films and blood cultures. As we have found no previous record of a Trypanosoma (Megatrypanum) species naturally infecting a member of the family Echimyidae, or any other caviomorph rodent, we conclude that this is the first time such an infection has been reported. The new species is unusual in the subgenus for its infectivity to laboratory mice. PMID:24309069

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

    PubMed

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

    1981-09-01

    In Colombia, the natural intermediate host of Echinococcus vogeli Rausch and Bernstein, 1972 is the paca, Cuniculus paca L. (Rodentia: Dasyproctidae). The larval cestode develops in the liver of the host, where it usually is situated superficially, partly exposed beneath Glisson's capsule. The infective larva consists of a subspherical to asymmetrical, fluid-filled vesicle, up to 30 mm in diameter, enclosed by a thick laminated membrane. It typically contains numerous chambers, often interconnected, produced by endogenous proliferation of germinal and laminated tissue, within which brood capsules arise in an irregular pattern from the germinal layer. Invasive growth by means of exogenous proliferation, typical of infections in man, was not observed in the natural intermediate host. The development of the larval cestode is described on the basis of material from pacas, supplemented by observations on early-stage lesions in experimentally infected nutrias, Myocastor coypus (Molina) (Rodentia: Capromyidae). The tissue response is characterized for early-stage, mature (infective), and degenerating larvae in the comparatively long-lived intermediate host. In addition to previously reported differences in size and form of rostellar hooks, other morphologic characteristics are defined by which the larval stage of E. vogeli is distinguished from that of E. oligarthrus (Diesing, 1863). Pathogenesis by the larval E. vogeli in man, like that by the larval E. multilocularis Leuckart, 1863, is the consequence of atypical proliferation of vesicles attributable to parasite-host incompatibility. PMID:7283003

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

    USGS Publications Warehouse

    Fisher, Robert D.; Ludwig, Craig A.

    2012-01-01

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

  1. Adaptive diversity of incisor enamel microstructure in South American burrowing rodents (family Ctenomyidae, Caviomorpha)

    PubMed Central

    Vieytes, Emma C; Morgan, Cecilia C; Verzi, Diego H

    2007-01-01

    The aim of this study was to analyse the morphofunctional and adaptive significance of variation in the upper incisor enamel microstructure of South American burrowing ctenomyids and other octodontoid taxa. We studied the specialized subterranean tooth-digger †Eucelophorus chapalmalensis (Pliocene – Middle Pleistocene), and compared it with other fossil and living ctenomyids with disparate digging adaptations, two fossorial octodontids and one arboreal echimyid. Morphofunctionally significant enamel traits were quite similar among the species studied despite their marked differences in habits, digging behaviour and substrates occupied, suggesting a possible phylogenetic constraint for the Octodontoidea. In this context of relative similarity, the inclination of Hunter–Schreger bands, relative thickness of external index (EI) and prismless enamel zone were highest in †Eucelophorus, in agreement with its outstanding craniomandibular tooth-digging specialization. Higher inclination of Hunter–Schreger bands reinforces enamel to withstand high tension forces, while high external index provides greater resistance to wear. Results suggest increased frequency of incisor use for digging in †Eucelophorus, which could be related to a more extreme tooth-digging strategy and/or occupancy of hard soils. Higher external index values as recurring patterns in distant clades of tooth-digging rodents support an adaptive significance of this enamel trait. PMID:17584181

  2. Biting performance and skull biomechanics of a chisel tooth digging rodent (Ctenomys tuconax; Caviomorpha; Octodontoidea).

    PubMed

    Becerra, Federico; Casinos, Adrià; Vassallo, Aldo Iván

    2013-02-01

    Biting performance is a key factor in vertebrate groups possessing particular food habits. In subterranean rodents that use the incisors as a digging tool, apart from requirements related to gnawing abrasive diets, the force exerted at the incisors tips must be sufficient to break down soils that are often exceedingly compact. The subterranean genus Ctenomys diversified in the southern portion of South America closely associated with the relatively open environments that characterize that region. This genus is considered a "claw and chisel tooth digger," that is, during the excavation of their galleries, the animals break down the soil with both the fore-claws and the incisors. We report here measurements of in vivo bite force in one of the largest species of the genus, C. tuconax, which occupies highland grasslands with compacted soils. We document the combined use of claws and incisors observed under field conditions, also providing measurements of soil compaction in the habitat occupied by this species. We report estimates of bite force at the level of the incisors and cheek teeth calculated from the physiological cross-sectional area of jaw muscles. To this aim, anatomical and biomechanical analyses of the mandibular apparatus were performed in preserved specimens. We found that C. tuconax bites with a higher force than expected for a mammal of its size. To assess anatomical correlates of biting performance, the morphology of the skull and jaw, and incisor second moment of area were compared with those of other caviomorph rodents with different lifestyle. PMID:23203312

  3. Capture of syncytin-Mar1, a fusogenic endogenous retroviral envelope gene involved in placentation in the Rodentia squirrel-related clade.

    PubMed

    Redelsperger, François; Cornelis, Guillaume; Vernochet, Cécile; Tennant, Bud C; Catzeflis, François; Mulot, Baptiste; Heidmann, Odile; Heidmann, Thierry; Dupressoir, Anne

    2014-07-01

    Syncytin genes are fusogenic envelope protein (env) genes of retroviral origin that have been captured for a function in placentation. Within rodents, two such genes have previously been identified in the mouse-related clade, allowing a demonstration of their essential role via knockout mice. Here, we searched for similar genes in a second major clade of the Rodentia order, the squirrel-related clade, taking advantage of the complete sequencing of the ground squirrel Ictidomys tridecemlineatus genome. In silico search for env genes with full coding capacity identified several candidate genes with one displaying placenta-specific expression, as revealed by quantitative reverse transcription-PCR analysis of a large panel of tissues. This gene belongs to a degenerate endogenous retroviral element, with recognizable hallmarks of an integrated provirus. Cloning of the gene in an expression vector for ex vivo cell-cell fusion and pseudotype assays demonstrated fusogenicity on a large panel of mammalian cells. In situ hybridization on placenta sections showed specific expression in domains where trophoblast cells fuse into a syncytiotrophoblast at the fetomaternal interface, consistent with a role in syncytium formation. Finally, we show that the gene is conserved among the tribe Marmotini, thus dating its capture back to about at least 25 million years ago, with evidence for purifying selection and conservation of fusogenic activity. This gene that we named syncytin-Mar1 is distinct from all seven Syncytin genes identified to date in eutherian mammals and is likely to be a major effector of placentation in its related clade. Importance: Syncytin genes are fusogenic envelope genes of retroviral origin, ancestrally captured for a function in placentation. Within rodents, two such genes had been previously identified in the mouse-related clade. Here, in the squirrel-related rodent clade, we identified the envelope gene of an endogenous retrovirus with all the features of a Syncytin: it is specifically expressed in the placenta of the woodchuck Marmota monax, at the level of cells fusing into a syncytium; it can trigger cell-cell and virus-cell fusion ex vivo; and it has been conserved for >25 million years of evolution, suggesting an essential role in its host physiology. Remarkably, syncytin-Mar1 is unrelated to all other Syncytin genes identified thus far in mammals (primates, muroids, carnivores, and ruminants). These results extend the range of retroviral envelope gene "domestication" in mammals and show that these events occurred independently, on multiple occasions during evolution to improve placental development in a process of convergent evolution. PMID:24789792

  4. Capture of syncytin-Mar1, a Fusogenic Endogenous Retroviral Envelope Gene Involved in Placentation in the Rodentia Squirrel-Related Clade

    PubMed Central

    Redelsperger, François; Cornelis, Guillaume; Vernochet, Cécile; Tennant, Bud C.; Catzeflis, François; Mulot, Baptiste; Heidmann, Odile; Dupressoir, Anne

    2014-01-01

    ABSTRACT Syncytin genes are fusogenic envelope protein (env) genes of retroviral origin that have been captured for a function in placentation. Within rodents, two such genes have previously been identified in the mouse-related clade, allowing a demonstration of their essential role via knockout mice. Here, we searched for similar genes in a second major clade of the Rodentia order, the squirrel-related clade, taking advantage of the complete sequencing of the ground squirrel Ictidomys tridecemlineatus genome. In silico search for env genes with full coding capacity identified several candidate genes with one displaying placenta-specific expression, as revealed by quantitative reverse transcription-PCR analysis of a large panel of tissues. This gene belongs to a degenerate endogenous retroviral element, with recognizable hallmarks of an integrated provirus. Cloning of the gene in an expression vector for ex vivo cell-cell fusion and pseudotype assays demonstrated fusogenicity on a large panel of mammalian cells. In situ hybridization on placenta sections showed specific expression in domains where trophoblast cells fuse into a syncytiotrophoblast at the fetomaternal interface, consistent with a role in syncytium formation. Finally, we show that the gene is conserved among the tribe Marmotini, thus dating its capture back to about at least 25 million years ago, with evidence for purifying selection and conservation of fusogenic activity. This gene that we named syncytin-Mar1 is distinct from all seven Syncytin genes identified to date in eutherian mammals and is likely to be a major effector of placentation in its related clade. IMPORTANCE Syncytin genes are fusogenic envelope genes of retroviral origin, ancestrally captured for a function in placentation. Within rodents, two such genes had been previously identified in the mouse-related clade. Here, in the squirrel-related rodent clade, we identified the envelope gene of an endogenous retrovirus with all the features of a Syncytin: it is specifically expressed in the placenta of the woodchuck Marmota monax, at the level of cells fusing into a syncytium; it can trigger cell-cell and virus-cell fusion ex vivo; and it has been conserved for >25 million years of evolution, suggesting an essential role in its host physiology. Remarkably, syncytin-Mar1 is unrelated to all other Syncytin genes identified thus far in mammals (primates, muroids, carnivores, and ruminants). These results extend the range of retroviral envelope gene “domestication” in mammals and show that these events occurred independently, on multiple occasions during evolution to improve placental development in a process of convergent evolution. PMID:24789792

  5. The largest fossil rodent

    PubMed Central

    Rinderknecht, Andrés; Blanco, R. Ernesto

    2008-01-01

    The discovery of an exceptionally well-preserved skull permits the description of the new South American fossil species of the rodent, Josephoartigasia monesi sp. nov. (family: Dinomyidae; Rodentia: Hystricognathi: Caviomorpha). This species with estimated body mass of nearly 1000?kg is the largest yet recorded. The skull sheds new light on the anatomy of the extinct giant rodents of the Dinomyidae, which are known mostly from isolated teeth and incomplete mandible remains. The fossil derives from San José Formation, Uruguay, usually assigned to the Pliocene–Pleistocene (4–2?Myr ago), and the proposed palaeoenvironment where this rodent lived was characterized as an estuarine or deltaic system with forest communities. PMID:18198140

  6. Molecular evolution of the nuclear von Willebrand factor gene in mammals and the phylogeny of rodents.

    PubMed

    Huchon, D; Catzeflis, F M; Douzery, E J

    1999-05-01

    Nucleotide sequences of exon 28 of the von Willebrand Factor (vWF) were analyzed for a representative sampling of rodent families and eutherian orders, with one marsupial sequence as outgroup. The aim of this study was to test if inclusion of an increased taxonomic diversity in molecular analyses would shed light on three uncertainties concerning rodent phylogeny: (1) relationships between rodent families, (2) Rodentia monophyly, and (3) the sister group relationship of rodents and lagomorphs. The results did not give evidence of any particular rodent pattern of molecular evolution relative to a general eutherian pattern. Base compositions and rates of evolution of vWF sequences of rodents were in the range of placental variation. The 10 rodent families studied here cluster in five clades: Hystricognathi, Sciuridae and Aplodontidae (Sciuroidea), Muridae, Dipodidae, and Gliridae. Among hystricognaths, the following conclusions are drawn: a single colonization event in South America by Caviomorpha, a paraphyly of Old World and New World porcupines, and an African origin for Old World porcupines. Despite a broader taxonomic sampling diversity, we did not obtain a robust answer to the question of Rodentia monophyly, but in the absence of any other alternative, we cannot reject the hypothesis of a single origin of rodents. Moreover, the phylogenetic position of Lagomorpha remains totally unsettled. PMID:10335651

  7. The hip adductor muscle group in caviomorph rodents: anatomy and homology.

    PubMed

    García-Esponda, César M; Candela, Adriana M

    2015-06-01

    Anatomical comparative studies including myological data of caviomorph rodents are relatively scarce, leading to a lack of use of muscular features in cladistic and morphofunctional analyses. In rodents, the hip adductor muscles constitute an important group of the hindlimb musculature, having an important function during the beginning of the stance phase. These muscles are subdivided in several distinct ways in the different clades of rodents, making the identification of their homologies hard to establish. In this contribution we provide a detailed description of the anatomical variation of the hip adductor muscle group of different genera of caviomorph rodents and identify the homologies of these muscles in the context of Rodentia. On this basis, we identify the characteristic pattern of the hip adductor muscles in Caviomorpha. Our results indicate that caviomorphs present a singular pattern of the hip adductor musculature that distinguishes them from other groups of rodents. They are characterized by having a single m. adductor brevis that includes solely its genicular part. This muscle, together with the m. gracilis, composes a muscular sheet that is medial to all other muscles of the hip adductor group. Both muscles probably have a synergistic action during locomotion, where the m. adductor brevis reinforces the multiple functions of the m. gracilis in caviomorphs. Mapping of analyzed myological characters in the context of Rodentia indicates that several features are recovered as potential synapomorphies of caviomorphs. Thus, analysis of the myological data described here adds to the current knowledge of caviomorph rodents from anatomical and functional points of view, indicating that this group has features that clearly differentiate them from other rodents. PMID:25911542

  8. Biology Index Page DSC Home Page ORDER Family Genus species Common Name

    E-print Network

    de Lijser, Peter

    species Common Name RODENTIA Heteromyidae Dipodomys deserti Desert Kangaroo Rat RODENTIA Heteromyidae Dipodomys merriami Merriam Kangaroo Rat RODENTIA Heteromyidae Perognathus longimembris Little Pocket Mouse

  9. A glimpse on the pattern of rodent diversification: a phylogenetic approach

    PubMed Central

    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 light on the macroevolution of many taxonomic groups such as the placentals (Mammalia). However, despite the increase of studies addressing the diversification patterns of organisms, no synthesis has addressed the case of the most diversified mammalian clade: the Rodentia. Results Here we present a rodent maximum likelihood phylogeny inferred from a molecular supermatrix. It is based on 11 mitochondrial and nuclear genes that covers 1,265 species, i.e., respectively 56% and 81% of the known specific and generic rodent diversity. The inferred topology recovered all Rodentia clades proposed by recent 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 in diversification rates within the major clades: two in Castorimorpha, three in Ctenohystrica, 6 within the squirrel-related clade and 24 in the Myomorpha clade. The majority of these shifts occurred within the most recent familial rodent radiations: the Cricetidae and Muridae clades. Using the topological imbalances and the time line we discuss the potential role of different diversification factors that might have shaped the rodents radiation. Conclusions The present glimpse on the diversification pattern of rodents can be used for further comparative meta-analyses. Muroid lineages have a greater degree of variation in their diversification rates than any other rodent group. Different topological signatures suggest distinct diversification processes among rodent lineages. In particular, Muroidea and Sciuroidea display widespread distribution and have undergone evolutionary and adaptive radiation on most of the continents. Our results show that rodents experienced shifts in diversification rate regularly through the Tertiary, but at different periods for each clade. A comparison between the rodent fossil record and our results suggest that extinction led to the loss of diversification signal for most of the Paleogene nodes. PMID:22697210

  10. Complete mitochondrial genome of the Tamiops swinhoei (Rodentia: Sciuridae).

    PubMed

    Xu, Peng; Li, Yankuo; Guo, Yingrong; Cheng, Songlin; Lei, Ping

    2014-11-27

    Abstract The complete mitochondrial genome of Tamiops swinhoei has been determined in this study. It is 16,513?bp in size and consists of 2 rRNA genes, 13 protein-coding genes, 22 tRNA genes and one non-coding region (D-loop). The overall base composition of the heavy strand of the T. swinhoei mitochondrial genome is A: 32.63%, T: 28.67%, C: 26.33% and G: 12.37%. The alignment of the Tamiops species control regions exhibited high genetic variability and rich A?+?T content (63.42%). PMID:25427814

  11. FIRST PLEISTOCENE JUMPING MOUSE (ZAPUS, ZAPODINAE, RODENTIA) FROM UTAH

    Microsoft Academic Search

    Dennis R. Ruez; Christopher J. Bell

    Two of the Little Dell Dam fossil localities produced the 1st Pleistocene records of the jumping mouse Zapus from Utah. We describe these teeth in detail and compare their morphology with both extinct and extant jumping mouse taxa. Although it is not possible to confidently assign these specimens to a particular species, the Little Dell Dam fossils are clearly distinct

  12. Population Genetics of Kangaroo Mice, Microdipodops (Rodentia: Heteromyidae) 

    E-print Network

    Andersen, John

    2012-07-16

    Dark (Microdipodops megacephalus) and pallid (Microdipodops pallidus) kangaroo mice are ecological specialists found in arid regions of the Great Basin Desert of the southwestern United States. Historical and current habitat ...

  13. Metabolism and thermoregulation in the Cabrera vole (Rodentia: Microtus cabrerae).

    PubMed

    Mathias, M L; Klunder, M; Santos, S M

    2003-10-01

    Metabolism and thermoregulation were studied for the first time in the Cabrera vole (Microtus cabrerae), an endemic and threatened rodent of the Iberian Peninsula. Low values of resting metabolic rate (RMR) were registered (1.13 mlO(2) g(-1) h(-1)) at the lower limit of the thermoneutral zone (TNZ) (around 33.5 degrees C). Body temperature increased near the TNZ up to 37.3 degrees C but remained stable, around 36 degrees C, at ambient temperatures below 25 degrees C. Values of thermal conductance remained quite stable at ambient temperatures of 10-25 degrees C (0.144-0.160 mlO(2) g(-1) h(-1) degrees C) and increased to 0.301 mlO(2) g(-1) h(-1) degrees C at 33.5 degrees C. Data revealed that M. cabrerae developed a highly adaptive ability of conserving energy and lowering the metabolic cost of thermoregulation at high ambient temperatures, allowing the body temperature to approximate that of the environment and exhibiting low resting metabolic rate and high conductance. PMID:14511762

  14. Population Genetics of Kangaroo Mice, Microdipodops (Rodentia: Heteromyidae)

    E-print Network

    Andersen, John

    2012-07-16

    Dark (Microdipodops megacephalus) and pallid (Microdipodops pallidus) kangaroo mice are ecological specialists found in arid regions of the Great Basin Desert of the southwestern United States. Historical and current habitat alterations have...

  15. Transcriptome sequencing and phylogenomic resolution within Spalacidae (Rodentia)

    PubMed Central

    2014-01-01

    Background Subterranean mammals have been of great interest for evolutionary biologists because of their highly specialized traits for the life underground. Owing to the convergence of morphological traits and the incongruence of molecular evidence, the phylogenetic relationships among three subfamilies Myospalacinae (zokors), Spalacinae (blind mole rats) and Rhizomyinae (bamboo rats) within the family Spalacidae remain unresolved. Here, we performed de novo transcriptome sequencing of four RNA-seq libraries prepared from brain and liver tissues of a plateau zokor (Eospalax baileyi) and a hoary bamboo rat (Rhizomys pruinosus), and analyzed the transcriptome sequences alongside a published transcriptome of the Middle East blind mole rat (Spalax galili). We characterize the transcriptome assemblies of the two spalacids, and recover the phylogeny of the three subfamilies using a phylogenomic approach. Results Approximately 50.3 million clean reads from the zokor and 140.8 million clean reads from the bamboo ratwere generated by Illumina paired-end RNA-seq technology. All clean reads were assembled into 138,872 (the zokor) and 157,167 (the bamboo rat) unigenes, which were annotated by the public databases: the Swiss-prot, Trembl, NCBI non-redundant protein (NR), NCBI nucleotide sequence (NT), Gene Ontology (GO), Cluster of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG). A total of 5,116 nuclear orthologous genes were identified in the three spalacids and mouse, which was used as an outgroup. Phylogenetic analysis revealed a sister group relationship between the zokor and the bamboo rat, which is supported by the majority of gene trees inferred from individual orthologous genes, suggesting subfamily Myospalacinae is more closely related to subfamily Rhizomyinae. The same topology was recovered from concatenated sequences of 5,116 nuclear genes, fourfold degenerate sites of the 5,116 nuclear genes and concatenated sequences of 13 protein coding mitochondrial genes. Conclusions This is the first report of transcriptome sequencing in zokors and bamboo rats, representing a valuable resource for future studies of comparative genomics in subterranean mammals. Phylogenomic analysis provides a conclusive resolution of interrelationships of the three subfamilies within the family Spalacidae, and highlights the power of phylogenomic approach to dissect the evolutionary history of rapid radiations in the tree of life. PMID:24438217

  16. Zur Morphologie des Zentralnervensystems von Erethizon dorsatum , Linnaeus (Rodentia, Hystricomorpha)

    Microsoft Academic Search

    G. Pilleri

    1960-01-01

    Das Gehirn von Erethizon dorsatum (E. dorsatum dorsatum, Linnaeus 1758) wird beschrieben. Es ergibt sich bei der Analyse von 6 Gehirnen aus der gleichen Subspecies eine starke Variabilität in der Form der Hemisphären. Der Quotient Hypothalamuslänge: Großhirnlänge schwankt zwischen 0,21 und 0,29 mit einem Durchschnittswert von 0,25 Für Hystrix cristata, hodgsoni und javanicus wurde ein Wert von 0,26 errechnet. Der

  17. Structural Features of Spines in Some Rodents (Rodentia: Myomorpha, Hystricomorpha)

    Microsoft Academic Search

    O. F. Chernova; G. V. Kuznetsov

    2001-01-01

    The architectonics of spines and hair was studied in Neacomys spinosus, Tokudaia osimensis, Arvicanthis somalicus, Leopoldamys sabanus, L. edwardsi, Maxomys moi, M. surifer, Niviventer fulvescens, N. confucianus, N. cremoriventer, Acomys cahirinus, A. somalica, Hystrix indica, H. cristata, Atherurus macrourus, Erethizon dorsatum, Proechimys steerei, and Lonchotrix emiliae. The presence of a dorsal longitudinal furrow covered by a modified cuticle is a

  18. [Structural characteristics of certain Rodents spines (Rodentia: Myomorpha, Hystricomorpha)].

    PubMed

    Chernova, O F; Kuznetsov, G V

    2001-01-01

    The architectonics of spines and hair was studied in Neacomys spinosus, Arvicanthis somalicus, Leopoldamys sabanus, L. edwardsi, Maxomys moi, M. surifer, Niviventer fulvescens, N. confucianus, N. cremoriventer, Acomys cahirinus, A. somalica, Hystrix indica, H. cristata, Atherurus macrourus, Erethizon dorsatum, Proechimys steerei, and Lonchotrix emiliae. The presence of a dorsal longitudinal furrow covered by a modified cuticle is a common structural feature of spines in all studied species except E. dorsatum, H. indica, and the frontal surface of the mosaic (scales located side by side) and terrace cuticle (steps between scales) varies in different species from smooth to rib-folded. A terminology has been proposed to describe the main structures of spine and hair. The adaptive significance of the spine architectonics in rodents is discussed. PMID:11525125

  19. MOLECULAR DIVERGENCE AND PHYLOGENETIC RELATIONSHIPS OF CHINCHILLIDS (RODENTIA: CHINCHILLIDAE)

    Microsoft Academic Search

    Angel E. Spotorno; John P. Valladares; Juan C. Marin; R. Eduardo Palma; Carlos Zuleta R

    2004-01-01

    ?1 Molecular phylogenetic relationships were investigated in 6 species of Chinchillidae (Chinchilla lanigera, C. brevicaudata, Lagidium peruanum, L. viscacia, L. wolffsohni, and Lagostomus maximus), 1 species of Dinomyidae (Dynomys branickii), 1 of Abrocomidae (Abrocoma cinerea), and 1 of Octodontidae (Octodon degus) using the 1st 548 base pairs of the mitochondrial cytochrome-b gene. Maximum-parsimony and maximum- likelihood analyses consistently showed Chinchillidae

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

    NASA Astrophysics Data System (ADS)

    Bogi?evi?, Katarina; Nenadi?, Draženko; Mihailovi?, Dušan

    2012-02-01

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

  1. Complete mitochondrial genome of the Pallas's squirrel Callosciurus erythraeus (Rodentia: Sciuridae).

    PubMed

    Hu, Lanlin; Peng, Rui; Zou, Fangdong

    2014-10-16

    Abstract The complete mitochondrial genome of Pallas's squirrel (Callosciurus erythraeus) from Sichuan Province was sequenced and characterized in detail. It was 16,550?bp in length and composed of 13 protein-coding genes, 22 tRNAs, 2 rRNAs and 1 control region. The mitochondrial genome of C. erythraeus presented in this report will be useful for species identification, genetic variability and clarifying the controversial taxonomic status of genus Callosciurus. PMID:25319295

  2. Two new species of fossil Leggadina (Rodentia: Muridae) from Northwestern Queensland

    PubMed Central

    Godthelp, Henk

    2015-01-01

    Only three species of fossil murine have been described to date in Australia even though they are often found in fossil deposits and can be highly useful in understanding environmental change over time. Until now the genus Leggadina, a group of short-tailed mice that is particularly well adapted to an arid environment, was only known from two extant species: L. forresti and L. lakedownensis. Here two new fossil species of the genus are described from sites in northwestern Queensland. Leggadina gregoriensis sp. nov. comes from the Early Pleistocene Rackham’s Roost Site in the Riversleigh World Heritage Area and Leggadina macrodonta sp. nov. is from the Plio-Pleistocene Site 5C at Floraville Station. The evolution of the genus Leggadina and the lineage’s response to palaeoecological factors is considered. Taphonomy of the two fossil deposits is examined and shows marked differences in both faunal composition of the assemblages and preservation. Description of L. gregoriensis and L. macrodonta extends the known temporal range of the Leggadina lineage by over 2 million years.

  3. Southwestern Association of Naturalists Elevational Range Extension for the Hispid Cotton Rat, Sigmodon hispidus, (Rodentia

    E-print Network

    Southwestern Association of Naturalists Elevational Range Extension for the Hispid Cotton Rat. http://www.jstor.org #12;December 2002 ELEVATIONAL RANGE EXTENSION FOR THE HISPID COTTON RAT MexicoState University,Las Cruces,NM 88003-0003 * Correspondent:jldunnum@unm.edu The hispid cotton rat

  4. Predicting the potential distribution of Vexillata (Nematoda: Ornithostrongylidae) and its hosts (Mammalia: Rodentia) within America.

    PubMed

    Martínez-Salazar, E A; Escalante, T; Linaje, M; Falcón-Ordaz, J

    2013-12-01

    Species distribution modelling has been a powerful tool to explore the potential distribution of parasites in wildlife, being the basis of studies on biogeography. Vexillata spp. are intestinal nematodes found in several species of mammalian hosts, such as rodents (Geomyoidea) and hares (Leporidae) in the Nearctic and northern Neotropical regions. In the present study, we modelled the potential distribution of Vexillata spp. and their hosts, using exclusively species from the Geomyidae and Heteromyidae families, in order to identify their distributional patterns. Bioclimatic and topographic variables were used to identify and predict suitable habitats for Vexillata and its hosts. Using these models, we identified that temperature seasonality is a significant environmental factor that influences the distribution of the parasite genus and its host. In particular, the geographical distribution is estimated to be larger than that predicted for its hosts. This suggests that the nematode has the potential to extend its geographical range and also its spectrum of host species. Increasing sample size and geographical coverage will contribute to recommendations for conservation of this host-parasite system. PMID:23046734

  5. Spermophilus xanthoprymnus (Rodentia: Sciuridae) MUTLU KART GU R AND HAKAN GU R

    E-print Network

    Hayssen, Virginia

    of Biology, Faculty of Arts and Sciences, Ahi Evran University, As¸ik Pas¸a, 40100, Kirs¸ehir, Turkey Anatolia and adjacent Armenia and northwestern Iran. Its preferred elevation appears to range from about, phylogeography, sciurid, Turkey E 26 July 2010 American Society of Mammalogists Synonymy completed 1 December

  6. Multilocus systematics and non-punctuated evolution of Holarctic Myodini (Rodentia: Arvicolinae).

    PubMed

    Kohli, Brooks A; Speer, Kelly A; Kilpatrick, C William; Batsaikhan, Nyamsuren; Damdinbazar, Darmaa; Damdinbaza, Darmaa; Cook, Joseph A

    2014-07-01

    The tribe Myodini consists of five genera of forest and alpine voles (Alticola, Caryomys, Eothenomys, Hyperacrius and Myodes) distributed throughout the Holarctic. Because mitochondrial evidence has revealed paraphyly and polyphyly among genera, we apply the first multilocus tests to clarify taxonomy and phylogenetic relationships. Our analyses of 28 of 36 species within Myodini, including three not previously sequenced (A. montosa, A. albicaudus, and H. fertilis), identify four distinct clades and provide the first molecular evidence that Hyperacrius may not belong in Myodini. Myodes is paraphyletic, while polyphyly of Alticola reflects apparent ancient mitochondrial introgression. Diversification in this tribe was hypothesized to be tightly linked to Late Cenozoic climatic events, however, lineage through time analysis indicates diversification over the last 4 My was gradual and not strongly punctuated. PMID:24594062

  7. The taxonomic position of Tonkinomys daovantieni (Rodentia: Muridae) based on karyological and molecular data.

    PubMed

    Balakirev, Alexander E; Aniskin, Vladimir V; Tien, Tran Quang; Rozhnov, Viatcheslav V

    2013-01-01

    Tonkinomys daovantieni was recently described from Northern Vietnam, but very sparse information exists for the taxon. We report for the first time the karyotype of this species and investigate its phylogenetic position in the Dacnomys division using both mitochondrial and nuclear genetic data. The diploid chromosome number of the species is 2n=44. This chromosomal set consists of one submetacentric pair, one metacentric pair, and nineteen pairs of subtelocentric/acrocentric autosomes progressively decreasing in size. The X chromosome is submetacentric and approximately equal in size to the largest subtelocentric autosome. The Y chromosome is metacentric and equal in size to the smallest pair of autosomes. The phylogenetic reconstruction based on the Cyt b COI and GHR genes reveals that Saxotilomys paulinae, a species distributed in the karst formations of the Lao PDR, is the closest relative to T. daovantieni. These two taxa are similar not only in a number of morphological characters, but also in their major ecological preferences (both are petrophylic species associated with limestone karst formations). Based on our data, we can conclude that the similarities among the ecological adaptations, natural conditions and habitat preferences of these species are a reflection of their phylogenetic relationship. PMID:25277936

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

    PubMed Central

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

    2015-01-01

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

  9. Molecular phylogeny of the speciose vole genus Microtus (Arvicolinae, Rodentia) inferred from mitochondrial DNA sequences

    Microsoft Academic Search

    Maarit Jaarola; Natália Martínková; ?slam Gündüz; Cecilia Brunhoff; Jan Zima; Adam Nadachowski; Giovanni Amori; Nina S. Bulatova; Basil Chondropoulos; Stella Fraguedakis-Tsolis; Jorge González-Esteban; María José López-Fuster; Andrei S. Kandaurov; Haluk Kefelio?lu; Maria da Luz Mathias; Idoia Villate; Jeremy B. Searle

    2004-01-01

    Voles of the genus Microtus represent one of the most speciose mammalian genera in the Holarctic. We established a molecular phylogeny for Microtus to resolve contentious issues of systematic relationships and evolutionary history in this genus. A total of 81 specimens representing ten Microtus species endemic to Europe as well as eight Eurasian, six Asian and one Holarctic species were

  10. Akodon molinae (Rodentia Cricetidae), a new laboratory animal: breeding, management and reproductive performance

    Microsoft Academic Search

    Maria Susana Merani; Marta Susana Lizarralde

    1980-01-01

    Summary Akodon mol\\/nae, a vole mouse widely distributed in central Argentina, shows remarkable chromosome polymorphisms. It is one of the natural reservoirs of the aetiologic agent of haemorrhagic fever, and a laboratory colony could be of great help in investi- gating this disease. Pregnancy lasted 23 (range 21-25) days. Litters of 4-5 young were born to monogamous breeding pairs about

  11. Tamias umbrinus (Rodentia: Sciuridae) JANET K. BRAUN, AUBREY A. JOHNSON, AND MICHAEL A. MARES

    E-print Network

    Hayssen, Virginia

    umbrinus sedulus White, 1953b:573. Type locality ``from Mount Ellen, Henry Mountains, Garfield Coun- ty:53, 62. Name combination. Eutamias umbrinus umbrinus: White, 1953b:571. Name combination. Eutamias speciosus inyoensis Merriam, 1897:194, 202, 208. Type locality ``from White Mts., Inyo Co.,'' California

  12. Karyotypic variation in the Andean rodent Phyllotis xanthopygus (Waterhouse, 1837) (Rodentia, Cricetidae, Sigmodontinae)

    PubMed Central

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

    2014-01-01

    Abstract Phyllotis xanthopygus (Waterhouse, 1837) is an Andean rodent endemic to South America. Despite its wide geographical distribution in Argentina, few individuals have been studied on the cytogenetic level and only through conventional staining. In this work, chromosome characterization of Argentine samples of this species was performed using solid staining, C-banding and base-specific fluorochromes. Twenty two specimens were analyzed, collected in the provinces of Jujuy, Catamarca, and the north and south of Mendoza. All studied specimens showed 2n=38, having mostly the bi-armed autosomes, metacentric or submetacentric. Fundamental Number varied between 70 and 72. These changes were due to the presence of chromosome heteromorphisms in individuals from southern Mendoza and Jujuy. C-banding revealed pericentromeric blocks of constitutive heterochromatin in most chromosomes. Acrocentric chromosomes involved in heteromorphisms showed high variation in the amount of heterochromatin within and among populations. Additionally, banding with fluorochromes (DAPI and chromomycin A3) revealed homologous localization of AT and GC rich regions among chromosomes of the different populations analyzed. Comparisons among heteromorphic pairs suggested, however, that the variation might be the result of complex chromosome rearrangements, involving possibly amplifications and/or deletions of heterochromatic segments. These results are in accordance with molecular studies that indicate genetic variability within and among the populations of this taxon. PMID:25610549

  13. Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe

    E-print Network

    Horacek, Ivan

    -Holocene period. Rich Pliocene and Pleistocene fossil records both from Europe and China suggest rather continuous the discrepancy we reexamined a considerable part of the European fossil record of the genus (14 sites from MN15 in study design, data collection and analysis, decision to publish, or preparation of the manuscript

  14. Mitochondrial phylogeny reveals cryptic genetic diversity in the genus Niviventer (Rodentia, Muroidea).

    PubMed

    He, Kai; Jiang, Xue-Long

    2015-02-01

    Niviventer is a muroid genus with 17 species widely distributed in East and Southeast Asia. These animals are important components of both extant and fossil small mammal communities, and they are among the most common infectious agents in humans. In this study, we employed partitioned Bayesian and relaxed clock divergence dating analyses and included the Niviventer mitochondrial cytochrome b genes of from GenBank (n?=?223). Although the intra-generic relationships were not fully resolved, we recognized four major clades/subclades that could support further division of the genus. Paraphyletic and polyphyletic species were discovered, and 21 putative species were recognized through species delimitation analysis, which indicated an imperfect taxonomy and the existent of cryptic species. Molecular dating supported Niviventer origination in the late Miocene, and relatively higher diversification rates were observed in the late Pliocene and the Pleistocene, which might correlate with climate fluctuations. PMID:24021005

  15. Digital dissection of the masticatory muscles of the naked mole-rat, Heterocephalus glaber (Mammalia, Rodentia)

    PubMed Central

    Faulkes, Chris G.

    2014-01-01

    The naked mole-rat, Heterocephalus glaber, of the family Bathyergidae is a subterranean rodent that feeds on underground roots and tubers and digs extensive tunnel systems with its incisors. It is a highly unusual mammal with regard to its social structure, longevity, pain insensitivity and cancer resistance, all of which have made it the subject of a great deal of research in recent years. Yet, much of the basic anatomy of this species remains undocumented. In this paper, we describe the morphology of the jaw-closing musculature of the naked mole-rat, as revealed by contrast-enhanced micro-computed tomography. This technique uses an iodine stain to enable the imaging of soft tissues with microCT. The iodine-enhanced scans were used to create 3D reconstructions of the naked mole-rat masticatory muscles from which muscle masses were calculated. The jaw-closing musculature of Heterocephalus glaber is relatively very large compared to other rodents and is dominated by the superficial masseter, the deep masseter and the temporalis. The temporalis in particular is large for a rodent, covering the entirety of the braincase and much of the rear part of the orbit. The morphology of the masseter complex described here differs from two other published descriptions of bathyergid masticatory muscles, but is more similar to the arrangement seen in other rodent families. The zygomaticomandibularis (ZM) muscle does not protrude through the infraorbital foramen on to the rostrum and thus the naked mole-rat should be considered protrogomorphous rather than hystricomorphous, and the morphology is consistent with secondarily lost hystricomorphy as has been previously suggested for Bathyergidae. Overall, the morphology of the masticatory musculature indicates a species with a high bite force and a wide gape–both important adaptations for a life dominated by digging with the incisors. PMID:25024917

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

    PubMed

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

    2013-10-01

    Two previously unrecognized species of the genus Hymenolepis are described based on specimens obtained from murid rodent species Bullimus luzonicus , Apomys microdon , and Rattus everetti collected on Luzon Island, Philippines. Hymenolepis bicauda n. sp. differs from all known Hymenolepis spp. in relative position of the poral dorsal and ventral osmoregulatory canals, gravid uterus occupying less than half the length of proglottid, relatively few eggs, and the highly characteristic longitudinal split of proglottids at the end of the gravid strobila. Hymenolepis haukisalmii n. sp. differs from all known Hymenolepis spp. in the relative position of both poral and aporal dorsal and ventral osmoregulatory canals and uterus lacking dorsal and ventral diverticula. The shift in the relative position of the dorsal and ventral osmoregulatory canals was not known in Hymenolepis from rodents in other regions of the world and is reminiscent of the situation observed in Hymenolepis erinacei, parasitic in hedgehogs, and members of the genus Talpolepis, parasitic in moles. The cosmopolitan species Hymenolepis diminuta was the only member of the genus previously reported from the Philippines. PMID:23679835

  17. Home range and social behavior of three species of European Pitymys (Mammalia, Rodentia)

    Microsoft Academic Search

    Marco Salvioni

    1988-01-01

    Habits, home range, and social behavior of three species of voles of the genus Pitymys, P. multiplex, P. subterraneus, and P. savii, were studied in Tessin (Switzerland) by radioactive tagging. P. multiplex and P. savii are fossorial and often use the burrow systems of moles (Talpa); P. subterraneus moves around on the surface under dense vegetation. Males and females of

  18. Complete mitochondrial genome of a chipmunk species, Tamias sibiricus (Rodentia: Sciuridae) in Korea.

    PubMed

    Yoon, Kwang Bae; Cho, Jae Youl; Park, Yung Chul

    2013-11-14

    Abstract We sequenced the complete mitochondrial genome (KF668525) of Tamias sibiricus in South Korea. The mitogenome of the Korean chipmunk T. sibiricus was 16,558?bp long with base composition of 33.8% A, 31.1% T, 22.9% C and 12.2% G. Total nucleotide similarity of T. sibiricus and Marmota himalayana (JX069958) genomes was 80.4% ranging from 66.9% (D-loop region) to 97.3% (tRNA(Leu)((CUN))). The present study will contribute to understanding taxonomic status and genetic divergence of Northeast Asian T. sibiricus populations. PMID:24228685

  19. A new species of spiny pocket mouse (Rodentia: Heteromyidae: Heteromys) from northwestern Costa Rica

    E-print Network

    Anderson, Robert P.; Timm, Robert M.

    2006-03-01

    occur in three highland areas (Monteverde, Volcán Rincón de la Vieja–Volcán Santa María, and Cerro Cacao), but populations in these areas are probably disjunct, being separated by intervening lowlands. Heteromys nubicolens is likely widespread throughout...

  20. Two new species of Litomosoides (Nematoda: Onchocercidae) from pocket gophers (Rodentia: Geomyidae) in Colorado

    Microsoft Academic Search

    Scott Lyell Gardner; Gerald D. Schmidt

    1986-01-01

    Summary  Two new species of nematodes representing the genusLitomosoides were obtained from pocket gophers collected in the early 1960s and during 1982 in Colorado. Individuals ofLitomosoides thomomydis n. sp. were recovered from the abdominal cavities of two species of pocket gopher,Thomomys talpoides (Richardson) andT. bottae (Eydoux & Gervais). Nematodes representingL. westi n. sp. were recovered from the abdominal and pleural cavities

  1. Karyotypes of sixteen populations of the Thomomys talpoides complex of pocket Gophers ( Rodentia-Geomyidae )

    Microsoft Academic Search

    Charles S. Thaeler

    1968-01-01

    Chromosome material of mitotic bone marrow cells from 59 individuals representing 16 populations of Thomomys talpoides was studied. These populations were found in southern Wyoming, Colorado, northern New Mexico and northern Arizona. A limited amount of intrapopulation variation in form but not number of chromosomes was found. Bight distinct karyotypes were observed. These can be characterized by the following diploid

  2. Chromosomal speciation in a Rassenkreis of Venezuelan spiny rats (genus Proechimys, Rodentia, Echimyidae)

    Microsoft Academic Search

    Osvaldo A. Reig; Marisol Aguilera; María Alicia Barros; Myriam Useche

    1984-01-01

    A series of populations of spiny rats (Proechimys) of NW and N Central Venezuela were found to belong to a circle of species and subspecies which surrounds the Andes of M6rida-CordiUera de la Costa mountain axis. This 'Rassenkreis' consists of 6 successive karyomorphs which exhibit a stepped-dine distribution (2n = 42, 44, 46, 48, 50 and 62). Each of the

  3. Multilocus Phylogenetics of a Rapid Radiation in the Genus Thomomys (Rodentia: Geomyidae)

    Microsoft Academic Search

    NATALIA M. BELFIORE; Liang Liu; Craig Moritz

    2008-01-01

    Species complexes undergoing rapid radiation present a challenge in molecular systematics because of the possibility that ancestral polymorphism is retained in component gene trees. Coalescent theory has demonstrated that gene trees often fail to match lineage trees when taxon divergence times are less than the ancestral effective population sizes. Suggestions to increase the number of loci and the number of

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

    PubMed

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

    2008-12-01

    A cross-sectional survey was conducted to monitor and compare the prevalence of helminthes in rodents from Dakahlia and Menoufia governorates. The domestic rodents (271) were Rattus norvegicus, Rattus rattus frugivorous, Rattus r. alexandrinus, & Mus musculus. The overall prevalence of helminthes was 52.8%. In Dakahlia, 72/145 rats (49.6%) were infected. The highest prevalence of infection was in R. r. frugivorous 43 (60.4%), then R. r. alexandrinus 44 (47.7%), R. norvegicus 38 (44.7%), and the lowest was M. musculus 20 (40%). In Menoufia, 71/126 rats (56.3%) were infected. The highest prevalence of infection was in R. r. frugivorous 36 (77.7%), then M. musculus 27 (48.1%), R. norvegicus 23 (47.8%), and the lowest was in R. r. alexandrinus 40 (47.5%). A total of 24 species of helminthes (11 trematodes, 4 cestodes & 10 nematodes) were identified among the 271 rodents. The commonest trematode was Mesostephanus aegypticus followed by Stictodora tridactyla. The commonest cestode was Hymenolepis diminuta followed by Taenia taeniaformis. The commonest nematode was Capillaria hepatica followed by Trichurus muris. Given the zoonotic potential of rodents' parasites and since several residential, commercial, and agricultural sites exist in the examined geographic areas, the potential health risk should not be ignored. PMID:19209758

  5. Reservoir competence of Microtus pennsylvanicus (Rodentia: Cricetidae) for the Lyme disease spirochete, Borrelia burgdorferi

    USGS Publications Warehouse

    Markowski, D.; Ginsberg, H.S.; Hyland, K.E.; Hu, R.

    1998-01-01

    The reservoir competence of the meadow vole, Microtus pennsylvanicus Ord, for the Lyme disease spirochete, Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner was established on Patience Island, RI. Meadow voles were collected from 5 locations throughout Rhode Island. At 4 of the field sites, M. pennsylvanicus represented only 4.0% (n = 141) of the animals captured. However, on Patience Island, M. pennsylvanicus was the sole small mammal collected (n = 48). Of the larval Ixodes scapularis Say obtained from the meadow voles on Patience Island, 62% (n = 78) was infected with B. burgdorferi. Meadow voles from all 5 locations were successfully infected with B. burgdorferi in the laboratory and were capable of passing the infection to xenodiagnostic I. scapularis larvae for 9 wk. We concluded that M. pennsylvanicus was physiologically capable of maintaining B. burgdorferi infection. However, in locations where Peromyscus leucopus (Rafinesque) is abundant, the role of M. pennsylvanicus as a primary reservoir for B. burgdorferi was reduced.

  6. Geometric morphometrics of the scapula of South American caviomorph rodents (Rodentia: Hystricognathi): Form, function and phylogeny

    Microsoft Academic Search

    Cecilia C. Morgan

    2009-01-01

    The scapula of the ecomorphologically diverse South American caviomorph rodents was studied through geometric morphometric techniques, using landmarks and semilandmarks to capture the shape of this complex morphological structure. Representatives of 33 species from all caviomorph superfamilies, as well as Hystrix cristata for comparisons, were analyzed. Marked differences in scapular shape were found among the major caviomorph lineages analyzed, particularly

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

    PubMed

    Gallina, Sonia; Pérez-Torres, Jairo; Guzmán-Aguirre, Carlos César

    2012-09-01

    Cuniculus paca is widely distributed throughout the Neotropics. Known as the paca, it is the largest rodent in the Mexican tropical forests, and one of the most used as a subsistence species for its meat. Since colonial times, this species has been subject of an unreported hunting pressure. For this reason, the aim of this work was to describe the use of the paca by the inhabitants of the Sierra de Tabasco State Park (STSP) using sampling areas in a matrix of vegetation with different degrees of disturbance, and different types of land use. We included both preserved areas: owing to the presence of large continuous areas of fragmented rainforest and areas that are not preserved, with smaller rainforest fragments and more isolated. To obtain information about paca use, we interviewed 176 people (>18 years old) who live in the STSP. All those interviewed had eaten paca meat, and indicated that this species is most frequently observed in the rainforest during the dry season. Hunting and trapping were the most common ways to obtain pacas, rather than gifting or purchasing, and firearms and dogs are used to hunt them. We estimated that these interviewed group had hunted a total of 488 paca in the year prior to the study. PMID:23025103

  8. Trends of Specialisation in Rodents: the Five-toed Jerboas, Subfamily Allactaginae (Dipodoidea, Rodentia)

    Microsoft Academic Search

    Andrei Miljutin

    2008-01-01

    Five-toed jerboas are bipedal rodents, which inhabit arid areas of Palaearctic Eurasia and North-East Africa. Three genera and about 15 species are recognised. The main goals of this study were: (1) to estimate the levels and trends of specialisation of the five-toed jerboas, (2) to reconstruct the course of their adaptive evolution. The results confirm that the adaptive evolution of

  9. C-banded karyotype of Myocastor coypus (Molina, 1782) from Turkey (Mammalia: Rodentia).

    PubMed

    Iliker, Ay?egül; Arslan, Atilla; Pamuko?lu, Nahit; Albayrak, Irfan

    2009-01-01

    The present study reports the C-band patterns of chromosomes of Myocastor coypus from Turkey. The karyotype of M. coypus is comprised of (2n) 42 chromosomes, the number of chromosomal arms (FN) was 83 and the number of autosomal arms (FNa) was 80. The X chromosome was a medium-sized metacentric and the Y chromosome was acrocentric and the smallest in the set. Two metacentric chromosomes have secondary constrictions. Most autosomes in this species were centromeric C-positive and some autosomes had telomeric C-bands. The X chromosome has centromeric heterochromatin, while the Y chromosome appeared to be entirely heterochromatic. PMID:19459458

  10. Landscape correlates of the distribution of coypu Myocastor coypus (Rodentia, Mammalia) in Argentinean Pampas

    Microsoft Academic Search

    L. R. Leggieri; M. L. Guichón; M. H. Cassini

    2011-01-01

    The coypu is a rodent indigenous to aquatic habitats in southern South America, which is considered a pest where it has been introduced and a valuable furbearer resource within its native range. The objective of this study was to identify the main landscape correlates of coypu distribution in the Pampas. Previous studies provided two non-exclusive hypotheses: (1) if hunting pressure

  11. Observations on the fetal morphology in Myocastor coypus bonariensis (coypu) (Rodentia, Myocastoridae).

    PubMed

    Felipe, A E; Masson, P G

    2008-12-01

    The goal of this work was to characterize the morphology of fetuses of Myocastor coypus bonariensis (coypu) after 60, 90, 120 and 135 days post-coitus (d.p.c.). At all the ages, gestational sacs showed an elliptical shape. Placentas were discoidal, with a unilobular external appearance in fetuses of 60 d.p.c. and with lobulations separated by a groove in fetuses of other ages. The umbilical cord, wrapped around the fetal body, showed a proximal dilatation in 60-d.p.c. fetuses, being its course uniform and a little spiral in the other ages. The 60-d.p.c. fetuses showed differentiation of corporal regions, prominent encephalic vesicles and little developed earlobes located in the laterals of the skull, in the limit with the cervical area and in straight line with the optical vesicles. The primitive forelimbs showed differentiation of arm, forearm and hand. In the hindlimbs, the inter-digital membrane was observed joining the fingers along all their length. Fetuses of 90 d.p.c. showed developed eyelids and closed palpebral cleft, developed auricular pavilions (earlobes), hairy follicles in the facial region (vibrissae) and in the skull and bent limbs. Fetuses of 120 and 135 d.p.c. showed a bodily cover constituted by a dense pilous covering, spread palpebral clefts, open mouth, bent limbs and inter-digital membranes in the hindlimbs. PMID:19032632

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

    PubMed

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

    2014-04-01

    In this study, we use three mitochondrial markers, cytochrome b gene (Cyt b), NADH dehydrogenase subunit 4 (ND4) and control region (D-loop) to investigate the phylogenetic relationships of extant zokor species in Mysopalacinae. The phylogenetic tree constructed based on Cyt b strongly supports the monophyly genera Eospalax and Myospalax with E. fontanierii being the most ancient species in Eospalax. Further phylogenetic analyses of four species of Eospalax based on ND4 and D-loop sequences revealed two clades that correspond to two geographical distributions. The basal clade includes E. cansus which is mainly found on Loess Plateau (LP) and another clade including E. baileyi, E. smithii and E. rufescens that inhabits areas above 2000?m on Qinghai-Tibetan Plateau (QTP) and Qinling Mountains. Geographical events of QTP and LP may have played a major role in the diversification and evolution of Mysopalacinae. PMID:23607477

  13. Chromosomal characterizations in a restricted population of Geomys bursarius (Rodentia: Geomyidae) 

    E-print Network

    Stallings, Raymond L

    1978-01-01

    and translocations. Some of the chromosomal reawangements found. in Rorars are truely polymorphic. This ppsnuscript follows the style and. format of C to enetics and Ce'1 Genetics. Others are not found. within the same reproductive population and are zepresents... of fossozial t . 1 d * h ~G* d~fh, I variability is Rnown to occur within the same reproductive population (chzomosoma1 polymorphism) ~ More frequently, chromosomal vaziability among fossozial mamma1s occurs between different reproductive populations...

  14. Recent radiation in West African Taterillus (Rodentia, Gerbillinae): the concerted role of chromosome and climatic changes

    Microsoft Academic Search

    G Dobigny; V Aniskin; L Granjon; R Cornette; V Volobouev

    2005-01-01

    West African gerbils of the genus Taterillus constitute a complex of seven sibling species distributed from sudano-guinean to saharo-sahelian regions. They display radically rearranged karyotypes despite low genic divergence and a very recent differentiation, that is, within the last 0.4 Myr for the six most derived species. We here provide a comparison of the seven specific karyotypes and perform a

  15. Sphiggurus vestitus pruinosus (Mammalia, Rodentia, Erethizontidae): The Karyotype and its Phylogenetic Implications, Descriptive Notes

    Microsoft Academic Search

    J. L. Concepcion; J. Molinari

    1991-01-01

    Sphiggurus vestitus pruinosus, a porcupine from western Venezuela, has a karyotype with a diploid number (2n) of 42, and a fundamental number (FN) of 76. The autosomes consist of 34 metacentric and submetacentric, 2 subacrocentric, and 4 acrocentric chromosomes. The X?chromosome is submetacentric, and the Y?chromosome is acrocentric. This karyotype is identical in gross morphology to that of the North

  16. Occurrence of Dermacentor variabilis (Acari: Ixodidae) around a porcupine (Rodentia: Erthethizontidae) carcass at Camp Ripley, Minnesota.

    PubMed

    McNemee, Richard B; Sames, William J; Maloney, Francis A

    2003-01-01

    In May 2000, a dead porcupine (Erethizon dorsatum Culiver) was found on an infrequently traveled dirt road at Camp Ripley, MN. The presence of late instar Calliphoridae suggested that the porcupine died within the past 4 to 7 d. Adult carrion (Silphidae) and rove (Staphylinidae) beetles were observed under the carcass. In June, a large number of adult American dog ticks, Dermacentor variabilis (Say), were observed questing on the porcupine and the surrounding grass. Six zones were established around the carcass, and each zone was sampled for ticks once a month from June through September. Ticks were captured in June and July, and 93% were captured within 2 m of the carcass. Gases released as part of the decomposition process were believed to attract the ticks to the carcass. PMID:12597663

  17. Revision of the chewing louse genus Eutrichophilus (Phthiraptera: Trichodectidae) from the New World porcupines (Rodentia: Erethizontidae)

    E-print Network

    Timm, Robert M.; Price, Roger D.

    1994-03-01

    .Remarks—Eutrichophilussetosusisdistinctfrom allotherknownspeciesofthegenusbyhav-ingbothsexeswiththelongerdorsalheadsetae,thefemalewithgonapophysesandventralter-minaliachaetotaxy asinFigure5,andthemalewiththemesomeresfusedtoformacircle(fig.3).Eutrichophilussetosusisrestrictedindistribu- tiontoasinglehostspecies,theNorthAmericanporcupineErethizondorsatum.ItistheonlylousespeciesknownfromE.dorsatum...

  18. Phylogeny, evolution, and systematics of the Galea musteloides complex (Rodentia: Caviidae)

    E-print Network

    ) from the central Bolivian Andes, G. m. auceps (Thomas, 1911) from the Altiplano region around Lake Titicaca, and G. m. demissa (Thomas, 1921) from the Bolivian lowlands adjacent to the Andean foothills

  19. The taxonomy of Geomydoecus (Mallophaga: Trichodectidae) from the Geomys bursarius complex (Rodentia: Geomyidae)

    E-print Network

    Timm, Robert M.; Price, Roger D.

    1980-03-01

    , the “southern” group, is composed of G. ewingi, G. heaneyi, and G. subgeomydis. In no case did a single population of pocket gophers have more than 1 species of Geomydoecus parasitizing it. Two species of Geomydoecus were obtained on Long-tailed Weasels, Mustela...

  20. The evolution of ecomorphological traits within the Abrothrichini (Rodentia: Sigmodontinae): A bayesian phylogenetics approach

    Microsoft Academic Search

    Enrique Rodríguez-Serrano; R. Eduardo Palma; Cristián E. Hernández

    2008-01-01

    The generally accepted hypothesis regarding the origin of fossorial mammals proposes adaptive convergence from open environments towards the use of subterranean environments. We evaluated this hypothesis for South American mole-mice using conventional and Bayesian frameworks, with independent evidence. By using a molecular approach based on Cytochrome b and IRBP sequences, we evaluated phylogenetic relationships, time of origin, the ancestral trait

  1. Comparison of climate space and phylogeny of Marmota (Mammalia: Rodentia) indicates

    E-print Network

    California at Berkeley, University of

    for a relationship between phylogenetic distance and `climate distance' of species within a clade. There should and phylogenetic distance matrices, but this relationship explains only a small fraction of the variance phylogenetic relationships, modern range constraint by climate, and some connection between evolutionary

  2. Microtus californicus (Rodentia: Cricetidae) NICHOLE L. CUDWORTH AND JOHN L. KOPROWSKI

    E-print Network

    Hayssen, Virginia

    by Kellogg (1918:5). Arvicola edax Le Conte, 1853:405. Type locality ``Califor- nia;'' restricted to south. c. californicus (Peale, 1848:46). See above; edax Le Conte and trowbridgii Baird are synonyms. M. c

  3. Innervation of propatagial musculature in a flying squirrel, Glaucomys volans (Rodentia, Sciuridae).

    PubMed

    Chickering, J G; Sokoloff, A J

    1996-01-01

    The propatagium of gliding and flying mammals is of both functional and phylogenetic interest. The innervation of the propatagial muscle, platysma II, was studied with the axonal tracer wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) in a flying squirrel, Glaucomys volans. Injections of WGA-HRP into the proximal third of platysma II labeled motoneurons in the lateral part of the medial subdivision of the ipsilateral facial nucleus and in the ipsilateral ventral horn of the brachial enlargement. Injections into distal regions of platysma II labeled motoneurons in the ipsilateral ventral horn of spinal segments C5-C8 but not in the facial nucleus. Injections along the whole length of the muscle labeled afferent axons in the ipsilateral dorsal horn of spinal segments C4-T1. These results demonstrate a mixed facial and spinal motor innervation of propatagial musculature in the flying squirrel and indicate that this pattern of mixed innervation is more widespread among flying and gliding mammals than previously reported. Mixed facial and cervical propatagial innervation, independently derived in different flying and gliding mammals, may represent a common solution in the design of the propatagium. These findings complicate the use of propatagial muscle innervation patterns for the establishment of phylogenetic relationships among flying and gliding mammals. PMID:8834780

  4. On the Indian crested porcupine, Hystrix indica (Kerr, 1792) in Turkey (Mammalia: Rodentia).

    PubMed

    Arslan, Atilla

    2008-01-15

    This study presents some data about ecological, biological and taxonomical characteristics of Hystrix indica (Kerr, 1792) from Turkey. For this purpose characteristics of burrow, skull, tooth and measurements of external and cranial characters of two female H. indica from Turkey were investigated. It was concluded that our specimens are between the Middle East and Indian sub-region specimens in terms of morphometrical. It was also determined that there were roots in stomach contents of specimens. PMID:18817213

  5. [Phylogeny of the order Rodentia inferred from structural analysis of short retrotransposon B1].

    PubMed

    Veniaminova, N A; Vasetski?, N S; Lavrechenko, L A; Popov, S V; Kramerov, D A

    2007-07-01

    A large-scale study of short retroposon (SINE) B1 has been conducted in the genome of rodents from most of the known families of this mammalian order. The B1 nucleotide sequences of rodents from different families exhibited a number of characteristic features including substitutions, deletions, and tandem duplications. Comparing the distribution of these features among the rodent families, the currently discussed phylogenetic relationships were tested. The results of analysis indicated (1) an early divergence of Sciuridae and related families (Aplodontidae and Gliridae) from the other rodents; (2) a possible subsequent divergence of beavers (Castoridae); (3) a monophyletic origin of the group Hystricognathi, which includes several families, such as porcupines (Hystricidae) and guinea pigs (Caviidae); (4) a possible monophyletic origin of the group formed by the remaining families, including six families of mouselike rodents (Myodonta). Various approaches to the use of short retroposons for phylogenetic studies are discussed. PMID:17899810

  6. Field evaluation of some bait additives against Indian crested porcupine (Hystrix indica) (Rodentia: Hystricidae).

    PubMed

    Mushtaq, Muhammad; Hussain, Iftikhar; Mian, Afsar; Munir, Shahid; Ahmed, Irfan; Khan, Abdul Aziz

    2013-09-01

    This research study evaluated the effect of different additives on the bait consumption by Indian crested porcupine, a serious forest and agricultural pest, under field conditions. Different additives (saccharin, common salt, bone meal, fish meal, peanut butter, egg yolk, egg shell powder, yeast powder, mineral oil and coconut oil) at 2 and 5% each were tested for their relative preference, using groundnut-maize (1:1) as basic bait. All the additives were tested under a no-choice test pattern. For control tests, no additive was mixed with the basic bait. Saccharin at 5% concentration significantly enhanced the consumption of bait over the basic bait, while 2% saccharin supplemented bait resulted in a non-significant bait consumption. All other additives did not enhance the consumption of the bait material; rather, these worked as repellents. However, the repellency was lowest with the common salt, followed by egg yolk, egg shell powder, bone meal, peanut butter, mineral oil, fish meal and yeast powder, while coconut remained the most repellent compound. The present study suggested that groundnut-maize (1:1) supplemented with 5% saccharin was the preferred bait combination, and can be used with different rodenticides for the management of Indian crested porcupine. PMID:24020467

  7. Late Pleistocene and Holocene Microtus (Pitymys) (Rodentia: Cricetidae) in New Mexico

    Microsoft Academic Search

    Arthur H. Harris

    1988-01-01

    Microtus (Pitymys) meadensis and M. (P.) quasiater show no special relationship to each other within the subgenus, and both differ greatly from M. (P.) ochrogaster. Samples of fossil Microtus (Pitymys) from late Pleistocene sites in southeastern New Mexico differ from each other and from modern M. ochrogaster to about the same degree as do some populations of modern M. ochrogaster

  8. Heterochromatin and the DNA content in Geomys attwateri and G. breviceps (Rodentia: Geomyidae)

    E-print Network

    Burton, David Winston

    1986-01-01

    (Lasiurus intermedius) . However, only the centromer ic bands were C- band positive. Barr os and Patton ( 1985 ) also found heterogeneity in the staining characteristics of the heterochromatin in members of thy~hbtt gp fpktgph Measur ements of the CMA3...

  9. Phylogeography of a post-glacial colonizer: Microtus longicaudus (Rodentia: Muridae)

    Microsoft Academic Search

    C. J. Conroy; J. A. Cook

    2000-01-01

    The molecular phylogeography of Microtus longicaudus was investigated with DNA sequences of the mitochondrial cytochrome b gene. We used phylogenetic and pairwise distance methods to reconstruct the history of the species with particular emphasis on the Pacific Northwest. Genetic variation across the species was consistent with vicariant events during the Pleistocene and subsequent northern postglacial expansion following the reced- ing

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

    PubMed Central

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

    2012-01-01

    The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, Bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in Chile: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000–13,000 years ago). Neutrality tests and the “g” parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in southern Temperate Forests (and adjacent areas in Patagonia). From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean Chile using glacial retreats. PMID:22396751

  11. Chromosomal characterizations in a restricted population of Geomys bursarius (Rodentia: Geomyidae)

    E-print Network

    Stallings, Raymond L

    1978-01-01

    miles east of Bzazos River, Dogwood Tr. 11 0. 1 miles east of Junction F. M. 2818 d Hwy. 60 3 20 Somatic metaphase chromosome spreads were obtained primarily through a short term bone marrow culture technicue. The technique used. was similar...- t hll?'hh't g'-a thf dgahhM* Variability in diploid number ranged' between 68 to 72. Both geographic tal. t dplygyph ' I f dl G. R t The chromosomes were predominately acrocentric with the num'ber of biarmed elements ranging from 3 to 10...

  12. Vigilance and foraging behaviour in a social desert rodent, Microcavia australis (Rodentia Caviidae)

    Microsoft Academic Search

    Paula Taraborelli

    2008-01-01

    Microcavia australis is a social species, diurnal and native to South America. This rodent provides an opportunity for analyzing the relationship between group size and the vigilance and foraging behaviour of the lesser cavy in two populations inhabiting two risky sites (El Leoncito and Ñacuñán). The study should reveal the mechanisms used by M. australis to reduce predation risk (many-eyes

  13. Phylogeography of a post-glacial colonizer: Microtus longicaudus (Rodentia: muridae).

    PubMed

    Conroy, C J; Cook, J A

    2000-02-01

    The molecular phylogeography of Microtus longicaudus was investigated with DNA sequences of the mitochondrial cytochrome b gene. We used phylogenetic and pairwise distance methods to reconstruct the history of the species with particular emphasis on the Pacific Northwest. Genetic variation across the species was consistent with vicariant events during the Pleistocene and subsequent northern postglacial expansion following the receding Laurentide and Cordilleran ice sheets. The largest break (> 6% uncorrected sequence divergence) was found to exist between populations found southeast of the Colorado River (eastern Arizona, Colorado, Wyoming and New Mexico) and all other western populations. Other well-supported subclades were composed of samples from: (i) the islands and north coast of southeast Alaska; (ii) eastern Alaska, British Columbia, Washington and Oregon; and (iii) northern California, Idaho and Montana. Within subclades, divergence was low. Our results suggest that the close relationships among haplotypes within northern subclades are a result of recent colonization, whereas higher among-subclade divergence is caused by genetic differentiation during prolonged periods of isolation, possibly as a result of mid-Pleistocene climatic events. PMID:10672160

  14. Distributional Survey of Rare Small Mammals (Orders Insectivora, Chiroptera, and Rodentia)

    E-print Network

    California myotis (Myotis californicus) ......................................25 Fringed myotis (Myotis included: Neotoma albigula brevicauda, Myotis californicus, M. thysanodes, M. yumanensis, and Antrozous thysanodes)............................................25 Yuma myotis (Myotis yumanensis

  15. Nucleolus organizer regions and B-chromosomes of wood mice (mammalia, rodentia, Apodemus)

    SciTech Connect

    Boeskorov, G.G. [Yakutia Institute of Biology, Yakutsk (Russian Federation); Kartavtseva, I.V. [Biological Soil Institute, Vladivostok (Russian Federation); Zagorodnyuk, I.V. [Shmal`gausen Institute of Zoology, Kiev (Ukraine); Belyanin, A.N. [Saratov State Univ. (Russian Federation); Lyapunova, E.A. [Kol`tsov Institute of Developmental Biology, Moscow (Russian Federation)

    1995-02-01

    Distribution of nucleolus organizer regions (NORs) in karyotypes was studied in 10 species of wood mice, including Apodemus flavicollis, A. sylvaticus, A. uralensis (=A. microps), A. fulvipectus (=A. falzfeini), A. ponticus, A. hyrcanicus, A. mystacinus, A. agrarius, A. peninsulae, and A. speciosus. Peculiarities of NOR location in karyotypes can be used in interspecific diagnostics of wood mice. Intraspecific polymorphism of A. sylvaticus, A. agrarius, and A. peninsulae in terms of the number of NORs and their localization in chromosomes can serve as evidence for karyological differentiation in certain populations of these species. The minimum number of active NORs in mice of the genus Apodemus is two to four. Two A. flavicollis wood mice with karyotypes containing one small acrocentric B-chromosome (2n = 49) were identified among animals captured in Estonia. In A. peninsulae, B-chromosomes were found among animals captured in the following regions: the vicinity of Kyzyl (one mouse with 17 microchromosomes, 2n = 65); the vicinity of Birakan (two mice with one metacentric chromosome each, 2n = 49); and in the Ussuri Nature Reserve (one mouse with five B-chromosomes, including three metacentric and two dotlike chromosomes; 2n = 53). In the latter animal, the presence of NORs on two metacentric B-chromosomes was revealed; this is the first case of identification of active NORs on extra chromosomes of mammals. 29 refs., 4 figs., 1 tab.

  16. Burrow configuration of Persian jird Meriones persicus Blanford, 1875 (Rodentia: Muridae, Gerbillinae)

    Microsoft Academic Search

    Saeed Mohammadi; Mohammad Kaboli; Mansour Aliabadian; Vahid Mohammadi

    2011-01-01

    Persian jird Meriones persicus is a widespread species in Iranian plateau and is one of the commonest jirds in desert rodents of Iran. We studied architecture of Persian jird's burrow systems in the central part of its geographic range in Iran for the first time in south of Shah-Reza in Isfahan Province. Three types burrow were detected for this jird

  17. Loss of telomeric sites in the chromosomes of Mus musculus domesticus (Rodentia: Muridae) during Robertsonian rearrangements

    Microsoft Academic Search

    Indrajit Nanda; Sonja Schneider-Rasp; Heinz Winking; Michael Schmid

    1995-01-01

    Mouse chromosomes possessing multiple Robertsonian rearrangements (Rb chromosomes) have been examined using fluorescencein situ hybridization with the telomeric consensus sequence (TTAGGG)n. No hybridization signals were detected at the primary constriction of Rb chromosomes. This observation leads us to conclude that the formation of Rb chromosomes in the mouse is invariably associated with the loss of telomeric regions. More significantly, a

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

    PubMed

    Rybczynski, Natalia; Ross, Elizabeth M; Samuels, Joshua X; Korth, William W

    2010-01-01

    The extant beaver, Castor, has played an important role shaping landscapes and ecosystems in Eurasia and North America, yet the origins and early evolution of this lineage remain poorly understood. Here we use a geometric morphometric approach to help re-evaluate the phylogenetic affinities of a fossil skull from the Late Miocene of China. This specimen was originally considered Sinocastor, and later transferred to Castor. The aim of this study was to determine whether this form is an early member of Castor, or if it represents a lineage outside of Castor. The specimen was compared to 38 specimens of modern Castor (both C. canadensis and C. fiber) as well as fossil specimens of C. fiber (Pleistocene), C. californicus (Pliocene) and the early castorids Steneofiber eseri (early Miocene). The results show that the specimen falls outside the Castor morphospace and that compared to Castor, Sinocastor possesses a: 1) narrower post-orbital constriction, 2) anteroposteriorly shortened basioccipital depression, 3) shortened incisive foramen, 4) more posteriorly located palatine foramen, 5) longer rostrum, and 6) longer braincase. Also the specimen shows a much shallower basiocciptal depression than what is seen in living Castor, as well as prominently rooted molars. We conclude that Sinocastor is a valid genus. Given the prevalence of apparently primitive traits, Sinocastor might be a near relative of the lineage that gave rise to Castor, implying a possible Asiatic origin for Castor. PMID:21085579

  19. Heterochromatin and the DNA content in Geomys attwateri and G. breviceps (Rodentia: Geomyidae) 

    E-print Network

    Burton, David Winston

    1986-01-01

    21 38. 2 8 19. 0 5 11. 9 4. 8 3 38 1 18 4 5. 1 16 29. 1 23 54. 8 67 85. 6 6 10. 9 100 54. 0 16 8. 6 28 15. 1 8 4. 3 10 5. 4 21 11. 3 F|g. 1Hp fth t t bt *E. tG~ and races F and G, (~Geom s attwateri) in Burleson Co. Texas. U UJ U (3 Q... "-", )tt' 't E , t ' I $( tg V r I t; I L :r?l ~ ~ EJL I;-, ?-ii' c' + I( ! , 1;%. 'L , C g Fig. 8 C-band karyotype of a hybrid FxG individual, AK 7856. Group (a) chromosomes are biarmed elements, group (b) chromosomes are acrocentric...

  20. Peromyscus boylii (Rodentia: Cricetidae) MATINA C. KALCOUNIS-RUEPPELL AND TRACEY R. SPOON

    E-print Network

    Hayssen, Virginia

    _ kalcounis@uncg.edu (MCK-R) Department of Biology, University of Massachusetts, Boston, MA 02125, and Mystic Aquarium and Institute for Exploration, 55 Coogan Blvd., Mystic, CT 06355, USA (TRS) Abstract: Peromyscus

  1. Evaluation of squirrels (Rodentia: Sciuridae) as ecologically significant hosts for Anaplasma phagocytophilum in California.

    PubMed

    Nieto, Nathan C; Foley, Janet E

    2008-07-01

    Granulocytic anaplasmosis (GA), caused by Anaplasma phagocytophilum, is a potentially fatal, emerging rickettsial disease of humans, domestic animals, and wildlife. The purpose of this study was to determine whether sciurids from multiple areas of northern California were infested with ticks or exposed to or infected with A. phagocytophilum using polymerase chain reaction (PCR) and indirect-fluorescent antibody (IFA) serology. Sciurids of nine different tree- and ground-dwelling species were assessed: arboreal squirrels (western and eastern gray squirrels, Sciurus griseus and S. carolinensis, and Douglas squirrels, Tamiasciurus douglasii) but not northern flying squirrels (Glaucomys sabrinus) had greater evidence of exposure and current infection than did semiarboreal or ground dwelling sciurids (California ground squirrels, Spermophilus beecheyi, and chipmunks, Tamias spp.). Western gray squirrels had the most extensive exposure (70.7% seroprevalence and 12.1% PCR prevalence). Positive squirrels were identified in all regions where squirrels were collected. A logistic regression identified being a western gray squirrel (OR = 20.5, P = 2.95 X 10(-8)) and from the north coastal region of California (OR = 9.052, P = 1.41 X 10(-6)) as having the highest risk of exposure to A. phagocytophilum. Five of nine sciurid species had evidence of infestation with Ixodes pacificus or I. spinipalpis that could vector A. phagocytophilum. Extensive exposure from multiple areas suggests sciurids may be important in the maintenance of GA in California and indicates that studies of reservoir competence of these species are warranted. PMID:18714881

  2. The complete mitochondrial genome of the Mongolian gerbil, Meriones unguiculatus (Rodentia: Muridae: Gerbillinae).

    PubMed

    Kim, Eun Bae; Lee, Sang-Goo

    2014-09-01

    Abstract The complete mitochondrial genome of the Mongolian gerbil, Meriones unguiculatus, was sequenced. The 16,360?bp long genome has 37 genes typical for rodent mitogenomes, including 22 tRNA genes, 2 rRNA genes, and 13 protein-coding genes. The total GC content of the mitochondrial genome is 36.96% with the base composition of 32.61% A, 23.71% C, 13.24% G, and 30.44% T. Translational terminators of three genes (cytb, cox3, and nad4) were generated by the addition of 3' A residues to the mRNA. This novel rodent mitochondrial genome will provide comparable information for understanding the rodent mitochondrial evolution. PMID:25185794

  3. Cryptic Speciation and Chromosomal Repatterning in the South African Climbing Mice Dendromus (Rodentia, Nesomyidae)

    PubMed Central

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

    2014-01-01

    We evaluate the intra- and interspecific diversity in the four South African rodent species of the genus Dendromus. The molecular phylogenetic analysis on twenty-three individuals have been conducted on a combined dataset of nuclear and mitochondrial markers. Moreover, the extent and processes underlying chromosomal variation, have been investigated on three species by mean of G-, C-bands, NORs and Zoo-FISH analysis. The molecular analysis shows the presence of six monophyletic lineages corresponding to D. mesomelas, D. mystacalis and four lineages within D. cfr. melanotis with high divergence values (ranges: 10.6% – 18.3%) that raises the question of the possible presence of cryptic species. The first description of the karyotype for D. mesomelas and D. mystacalis and C- and G- banding for one lineage of D. cfr. melanotis are reported highlighting an extended karyotype reorganization in the genus. Furthermore, the G-banding and Zoo-FISH evidenced an autosome-sex chromosome translocation characterizing all the species and our timing estimates this mutation date back 7.4 mya (Late Miocene). Finally, the molecular clock suggests that cladogenesis took place since the end of Miocene to Plio-Pleistocene, probably due to ecological factors, isolation in refugia followed by differential adaptation to the mesic or dry habitat. PMID:24551165

  4. A newly recognized clade of trans-Andean Oryzomyini (Rodentia: Cricetidae), with description of a new genus.

    E-print Network

    Pine, Ronald H.; Timm, Robert M.; Weksler, Marcelo

    2012-06-01

    We expand upon recent studies on relationships within the Oryzomyini, in particular, those involving taxa currently assigned to the genus Sigmodontomys. In recent years, Sigmodontomys has been treated as including 2 ...

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

    PubMed

    Balakirev, Alexander E; Abramov, Alexei V; Rozhnov, Viatcheslav V

    2014-01-01

    Based on molecular data for mitochondrial (Cyt b, COI) and nuclear (IRBP, GHR) genes, and morphological examinations of museum specimens, we examined diversity, species boundaries, and relationships within and between the murine genera Chiromyscus and Niviventer. Phylogenetic patterns recovered demonstrate that Niviventer sensu lato is not monophyletic but instead includes Chiromyscuschiropus, the only previously recognized species of Chiropus. To maintain the genera Niviventer and Chiropus as monophyletic lineages, the scope and definition of the genus Chiromyscus is revised to include at least three distinct species: Chiromyscuschiropus (the type species of Chiromyscus), Chiromyscuslangbianis (previously regarded as a species of Niviventer), and a new species, described in this paper under the name Chiromyscusthomasi sp. n. PMID:25493050

  6. [The genetic links and species affiliation of the field mouse (Rodentia, Muridae, Sylvaemus) from the Pamir-Alai].

    PubMed

    Mezhzherin, S V

    1996-01-01

    Analysis of variation in 30 presumptive biochemical loci in Sylvaemus sylvaticus pallipes from Tadjikistan was carried out with reference to the geographically closely related species S. uralensis. The data obtained support the genetic identity of pallipes, on the one hand, and suggest a rather low level of genetic divergence (D'Nei = 0.154, Pfd = 13) from an ancestral taxon, on the other hand. Analysis of genetic variation of diagnostic morphological features suggests that pallipes is the most extreme form of geographic population series of the uralensis species group. Both genetic and morphometric data suggest that S. pallipes is an allospecies of the uralensis species complex. PMID:8640110

  7. A new species of Syphacia (Seuratoxyuris) (Nematoda: Oxyuridae) from Sooretamys angouya Fischer, 1814 (Rodentia: Cricetidae) in Argentina.

    PubMed

    Robles, María del Rosario; Panisse, Guillermo; Navone, Graciela Teresa

    2014-11-01

    Syphacia (Seuratoxyuris) hugoti n. sp. (Nematoda: Oxyuridae) is described from the cecum of Sooretamys angouya (Cricetidae: Sigmodontinae: Oryzomyini) captured in Formosa Province, Argentina. The diagnosis of the subgenus is emended, and the new species is separated from eight congeners by the distribution of submedian papillae and amphids, shape of the cephalic plate, presence of deirids, absence of cervical and lateral alae, length of the spicule, structure of the accessory hook of the gubernaculum and distance of excretory pore and vulva from the anterior extremity. The analysis suggests that S. (Se.) oryzomyos should be removed from Seuratoxyuris and redesignated as S. (Syphacia) oryzomyos n. comb. To date, of the species of Syphacia found in South and North American, 7 parasitize Oryzomyini rodents, of which two are distributed in Argentina. The present study constitutes the first record of the subgenus Seuratoxyuris from Argentina and the third record of a Syphacia species from rodents of the tribe Oryzomyini. PMID:24995650

  8. Mitochondrial DNA and karyotypic data confirm the presence of Mus indutus and Mus minutoides (Mammalia, Rodentia, Muridae, Nannomys) in Botswana

    PubMed Central

    McDonough, Molly M.; Sotero-Caio, Cibele G.; Ferguson, Adam W.; Lewis, Patrick J.; Tswiio, Matlhogonolo; Thies, Monte L.

    2013-01-01

    Abstract We use a combination of cytochrome b sequence data and karyological evidence to confirm the presence of Mus indutus and Mus minutoides in Botswana. Our data include sampling from five localities from across the country, including one site in northwestern Botswana where both species were captured in syntopy. Additionally, we find evidence for two mitochondrial lineages of M. minutoides in northwestern Botswana that differ by 5% in sequence variation. Also, we report that M. minutoides in Botswana have the 2n=34 karyotype with the presence of a (X.1) sex-autosome translocation. PMID:24363588

  9. New data on recently described rodent species Paulina's Limestone Rat Saxatilomys paulinae Musser, Smith, Robinson & Lunde, 2005 (Mammalia: Rodentia)

    PubMed Central

    Nguyen, Nghia Xuan; Ngo, Tuong Xuan; Nguyen, Duy Dinh

    2015-01-01

    Abstract Background Paulina's Limestone Rat Saxatilomys paulinae Musser et al., 2005 was first discovered by Musser et al. (2005) based on specimens from the Khammouane Limestone National Biodiversity Conservation Area (NBCA) in Khammouane Province in central Lao People's Democratic Republic (PDR). This tower karst landscape is part of the Central Indochina Limestone massif, which extends eastward into north-central Vietnam in Quang Binh and Quang Tri Provinces. New information In April 2014, we conducted a rodent survey and collected four (4) whole specimens of Saxatilomys paulinae in Quang Binh province. This is the first record of Saxatilomys paulinae in Vietnam. External and craniodental characteristics of all specimens clearly exhibit the characters of Saxatilomys paulinae as described in Musser et al. (2005)?. The rats are of medium size (HB: 160.3 ± 2.03 mm, T: 192.3 ± 6.69 mm) with some specific morpological characteristics. The external and craniodental measurement of the specimens from Vietnam tend to be larger than those of specimens from Lao. However, this needs to be verified by more studies in future. The habitat of Saxatilomys paulinae in Vietnam is characterized by complicated terrain comprising low karst towers (around 400 m) with steep slopes covered under limestone humid evergreen forest. The forest has been affected by selected timber logging in the past, but still has a complex 4-layer structure. The population of Saxatilomys paulinae in Vietnam is threatened by rodent trapping/snaring and habitat disturbance. More status surveys should be conducted to assess the species distributional range and its population status for undertaking relevant conservation measures. PMID:26023285

  10. Pyriproxyfen bait for control of plague vector fleas (Siphonaptera:Ceratophyllidae) on rock squirrels (Rodentia:Sciuridae)

    E-print Network

    Dietrich, Erin Bess Gabrielle

    2001-01-01

    and entomological trades to the best restaurants and chile, a plethora of knowledge about anything under the sun: fact or fiction, handling anthrax and watching plague bacteria fluoresce, hunting 'aranas del torro' by flashlight to the keys of Bigfoot and a caged...

  11. Community Analysis of Muridae (Mammalia, Rodentia) Diversity in Guinea: A Special Emphasis on Mastomys Species and Lassa Fever Distributions

    Microsoft Academic Search

    E. Lecompte; E. Calvet; M. D. Camara; A. Doré; K. Koulémou; F. Kourouma; B. Soropogui; O. Sylla; B. Allali-Kouadio; S. Kouassi-Kan; C. Akoua-Koffi; J. Meulen; L. Koivogui

    The Murid rodent diversity has been sampled following the 9th Meridian in the east of Guinea from the forest region to Sudanian savannas of southern Mali. This represents the first small\\u000a mammals survey in North Guinea. Murid diversity patterns have been researched using correspondence analysis and faunal comparisons.\\u000a A difference between southern forest communities and northern ones is observed. Mastomys

  12. A Remarkable Case of Micro-Endemism in Laonastes aenigmamus (Diatomyidae, Rodentia) Revealed by Nuclear and Mitochondrial DNA Sequence Data

    PubMed Central

    Nicolas, Violaine; Herbreteau, Vincent; Couloux, Arnaud; Keovichit, Kham; Douangboupha, Bounneuang; Hugot, Jean-Pierre

    2012-01-01

    L. aenigmamus is endemic to the limestone formations of the Khammuan Province (Lao PDR), and is strongly specialized ecologically. From the survey of 137 individuals collected from 38 localities, we studied the phylogeography of this species using one mitochondrial (Cyt b) and two nuclear genes (BFIBR and GHR). Cyt b analyses reveal a strong mtDNA phylogeographical structure: 8 major geographical clades differing by 5–14% sequence divergence were identified, most of them corresponding to distinct karst areas. Nuclear markers display congruent results but with a less genetic structuring. Together, the data strongly suggest an inland insular model for Laonastes population structure. With 8 to 16 evolutionary significant units in a small area (about 200×50 km) this represents an exceptional example of micro-endemism. Our results suggest that L. aenigmamus may represent a complex of species and/or sub-species. The common ancestor of all Laonastes may have been widely distributed within the limestone formations of the Khammuan Province at the end of Miocene/beginning of the Pliocene. Parallel events of karst fragmentation and population isolation would have occurred during the Pleistocene or/and the end of the Pliocene. The limited gene flow detected between populations from different karst blocks restrains the likelihood of survival of Laonastes. This work increases the necessity for a strict protection of this rare animal and its habitat and provides exclusive information, essential to the organization of its protection. PMID:23155377

  13. Two new subgenera of chewing lice (Phthiraptera: Trichodectidae) from pocket gophers (Rodentia: Geomyidae), with a key to all included taxa.

    PubMed

    Hellenthal, R A; Price, R D

    1994-05-01

    The new subgenera Thaelerius and Jamespattonius are described, respectively, for the eight species of Geomydoecus in the thomomyus complex of lice and the four species of Thomomydoecus in the wardi complex. Except for T. byersi Hellenthal & Price from Thomomys bottae (Eydoux & Gervais), these lice are restricted to the Thomomys talpoides (Richardson) complex of pocket gophers and are the only lice found on these hosts. A key is given for the identification of the currently recognized 122 taxa of pocket gopher lice. PMID:8057321

  14. Population dynamics and bioenergetics of a fossorial herbivore, Thomomys talpoides (Rodentia: Geomyidae), in a spruce-fir sere

    USGS Publications Warehouse

    Andersen, Douglas C.; MacMahon, James A.

    1981-01-01

    Studies of the bioenergetics of the northern pocket gopher, Thomomys talpoides, are coupled with data on demography, activity budgets, and microclimates to model the energy requirements of individuals and populations in the Wasatch Mountains of Utah during 1976-1979. Metabolic rates during rest increased linearly with decreasing ambient temperature, but burrowing metabolic rates (16.3 mL O2 • h-1 • g-9.75) were independent of both temperature and physical properties of the soil. Radio-telemetry studies indicated that free-ranging gophers are active =50% of each day. Conservative estimates of true energy consumption were calculated using estimates of habitat-specific minimum daily burrowing requirements. Rates of burrowing measured in the laboratory were either ? 0.0 or ? 2.0 cm/min. The low burrowing rate was observed when the soil was frozen or saturated with water, as would occur in the field in early winter and in spring, respectively. Gophers burrowed through soil at the study site at an average rate of ? 1.5 cm/min. Belowground food energy densities at gopher foraging depth declined from 24.6 to 3.2 J/cm3 along a successional gradient (subalpine forb meadow to Engelmann spruce dominated forest). We conclude that individual gophers are food limited within the climax spruce seral stage. Further, daily energy costs associated with reproduction in females may exceed the belowground energy supply available in intermediate seral stages (aspen and subalpine fir). Reduction of burrowing rates for any reason will affect gophers in the late seral stages proportionately more than those resident in the meadow. The peak gopher densities recorded (from 62 individuals/ha in the meadow to 2 individuals/ha in spruce forest) support these inferences. Detailed demographic information was obtained only in the meadow seral stage. Adult survivorship was lower in winter than in summer and varied greatly between years (0.18-0.70 yr-1). Juvenile survivorship from weaning through the first year was comparable to adult annual rates. The fertility rate was 3.75 young • female-1 • yr-1. The energy supply and demand analyses indicate that the growth of Thomomys talpoides populations in the early seral stages is seldom directly limited by the amount of food present. From our demographic, environmental, and autecological studies we conclude that stochastic events associated with weather affect energy acquisition (burrowing) rates, and thus survivorship. In montane environments, such events may prevent populations from attaining sizes at which territorial behavior would hypothetically limit further increases. The energy flow through the meadow population at moderate to high )1976-1977) densities (at least 1100 MJ • ha-1 • yr-1) indicates that pocket gophers are proficient energy movers relative to non-fossorial small mammals. Subalpine T. talpoides populations appear commonly to attain such densities. More than 30% of the annual primary productivity allocated to belowground parts of meadow forbs may be consumed by gophers.

  15. Yellow-bellied marmots ( Marmota flaviventris ) 'in the shape space' (Rodentia, Sciuridae): sexual dimorphism, growth and allometry of the mandible

    Microsoft Academic Search

    Andrea Cardini; Paolo Tongiorgi

    2003-01-01

    Geometric morphometrics was applied in a quantitative analysis of the morphology of the yellow-bellied marmot mandible. Five age classes were recognised by premolar toothwear, and the size and shape of the lower jaw were compared between sexes and among ages. Although the social role of adult males and females is markedly distinct, with the former mainly engaged to defend a

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

    PubMed Central

    2013-01-01

    Introduction Sexual size dimorphism (SSD) is a widespread phenomenon in animals including mammals. It has been demonstrated that across species, the direction and magnitude of sexual dimorphism in body size often corresponds to social systems. Moreover, many animal lineages conform to “Rensch’s rule”, which states that male-biased SSD increases with body size. We tested whether considerable differences in sociality and large variation in body size were connected with the evolution of SSD in the structural body size of ground squirrels, an otherwise ecologically relatively homogenous group of terrestrial rodents. Results We found the general trend of male-biased SSD in ground squirrels, however, male size increases nearly perfectly isometrically with female size among species and sociality does not explain departures from this relationship. Species with different sociality grades significantly differ in body size, with the most social species tending to be the largest. Conclusions We suggest that lack of conformity with Rensch´s rule in ground squirrels may be attributed to their low variation in SSD, and briefly discuss three potential causes of small magnitude of SSD in the structural size in rodents: low selection on SSD in structural dimensions, ontogenetic and genetic constraints and the existence of ecological/selection factors preventing the evolution of extensive SSD. PMID:23672689

  17. A new subgenus and four new species of Gliricola (Phthiraptera: Gyropidae) from the Caribbean hutias (Rodentia: Capromyidae)

    E-print Network

    Price, Roger D.; Timm, Robert M.

    1997-07-01

    A new subgenus, Hutiaphilus (Phthiraptera: Gyropidae), is described for five previously named species of Gliricola (G. armatus, G. capromydis, G. cubanus, G. ewingi, and G. omahonyi) and four new species (G. rabbi, with ...

  18. Genetic differentiation and relationship of the dipodids Allactaga and Jaculus (Mammalia, Rodentia) in Egypt based on protein variation

    Microsoft Academic Search

    Adel A. Basyouny Shahin

    2003-01-01

    Genetic differentiation among 14 populations representing all Egyptian dipodid (jerboa) species and subspecies was examined\\u000a at 25 structural loci and interspecific relationships are discussed. Of the 25 loci, only 3 were monomorphic, with the same\\u000a allele fixed in all taxa, 9 loci were monomorphic, but demonstrated intertaxon variation, and only 13 loci were polymorphic.\\u000a The overall mean number of alleles

  19. Patterns of spatial organization and behaviour of Pygeretmus pumilio Kerr, 1792 (Dipodidae, Rodentia): radiotelemetry study in the Dagestan desert, Russia

    Microsoft Academic Search

    K. A. Rogovin; E. J. Heske; G. I. Shenbrot

    1996-01-01

    A radiotelemetry study of the home range area and overlap of a herbivorous jerboa,Pygeretmus pumilioKerr, was conducted in a desert of northern Dagestan, Russia, during its spring breeding season. A high degree of mobility in this population was observed. Mean home range area was not significantly different between males and females in either the full moon or new moon tracking

  20. The Neogene mammalian faunas of Ertemte and Harr Obo in Inner Mongolia (Nei Mongol), China. — 12. Jerboas — Rodentia: Dipodidae

    Microsoft Academic Search

    Zhuding Qiu

    2003-01-01

    This paper describes three dipodids —Paralactaga suni\\u000a Teilhard & Young 1931,Brachyscirtetes wimani (Schlosser 1924) andSminthoides fraudator Schlosser 1924, collected by the Sino-German cooperative project in vertebrate palaeontology from Ertemte and Harr Obo, Inner\\u000a Mongolia, in 1980. The Ertemte fauna contains the most abundant dipodids known in the Chinese Neogene mammalian faunas. It\\u000a is shown that the three dipodines are endemic

  1. On the taxonomy of the lesser jerboa Jaculus jaculus (Dipodidae, Rodentia) in Tunisia based on allozymic and morphological variation

    Microsoft Academic Search

    Abderraouf BEN FALEH; Abdelwaheb BEN OTHMEN; Khaled SAID

    Génétique, Biodiversité et Valorisation des Bio-ressources (UR03ES09), Institut Supérieur de Biotechnologie de Monastir 5000, Tunisie Abstract The lesser Egyptian jerboa Jaculus jaculus, is a member of the subfamily Dipodinae, and is far known to have a complex of subspecies. Previous studies on J. jaculus from North Africa have shown the existence of various morphological forms of unknown taxonomic status, which

  2. Padrão de divisão e distribuição das artérias mesentéricas no ratão-do-banhado (Myocastor coypus - Rodentia: Mammalia)

    Microsoft Academic Search

    Gilberto Valente Machado; Pedro Renato Gonçalves; Adelvino Parizzi

    celíaca (70%), ou em tronco comum com esta (30%); b) os ramos diretos da artéria mesentérica cranial são as artérias pancreaticoduodenal caudal (100%), cólica média (100%), duodenojejunal (90%), pancre- ática (10%), hepática (10%), cólica direita (100%), jejunais (100%), ileocólica (100%) e ileal (100%). A artéria mesentérica caudal surge da face ventral da aorta abdominal, imediatamente cranial à emergência das artérias

  3. Modelling the distribution of an introduced species: The coypu Myocastor coypus (Mammalia, Rodentia) in Piedmont region, NW Italy

    Microsoft Academic Search

    S. Bertolino; B. Ingegno

    2009-01-01

    Model?based analyses of species–habitat relationships can help to clarify which factors influence the establishment and spread of species. The coypu (Myocastor coypus) is a semi?aquatic rodent native to South America, which has been introduced worldwide, including Italy. We used logistic regression to analyse the species distribution according to habitat attributes of agro?ecosystems in Piedmont Region. The resulting model correctly predicted

  4. Invertebrate dispersal by aquatic mammals: a case study with nutria Myocastor coypus (Rodentia, Mammalia) in Southern France

    Microsoft Academic Search

    Aline Waterkeyn; Olivier Pineau; Patrick Grillas; Luc Brendonck

    2010-01-01

    Many freshwater invertebrates rely on vectors for their passive dispersal. A wide array of vectors has already been investigated,\\u000a but dispersal mediated by aquatic mammals remains largely unknown. Since nutria (Myocastor coypus Molina, 1782) live in a variety of aquatic habitats and frequently move around between these water bodies, they have the\\u000a opportunity to transport hitch-hiking aquatic invertebrates along with

  5. Comparative FISH analysis of C-positive blocks of centromeric chromosomal regions of pygmy wood mice Sylvaemus uralensis (Rodentia, Muridae)

    Microsoft Academic Search

    T. V. Karamysheva; A. S. Bogdanov; I. V. Kartavtseva; T. V. Likhoshvay; M. N. Bochkarev; N. E. Kolcheva; V. V. Marochkina; N. B. Rubtsov

    2010-01-01

    The composition and homology of centromeric heterochromatin DNA has been compared in representatives of the Asian race and\\u000a two chromosomal forms (Eastern European and Southern European) of the European race of the pygmy wood mouse Sylvaemus uralensis by means of in situ hybridization with metaphase chromosomes of microdissection DNA probes obtained from centromeric C-blocks\\u000a of mice of the Southern European

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

    PubMed

    Tesakov, A S; Lopatin, A V

    2015-01-01

    A new genus and species of rodent, Lamugaulus olkhonensis, belonging to the subfamily Promylagaulinae of the family Mylagaulidae, is described on the basis of isolated teeth from the Khalagay Formation of the Lower Miocene Tagay locality (Olkhon island, Lake Baikal, Irkutsk Region). This is the first record of mylagaulids in Eastern Siberia, significantly expanding the data on the distribution of this mainly North American group of rodents in Asia and showing its presence outside the Central Asian arid zone. PMID:25773245

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

    Microsoft Academic Search

    Claudine Montgelard; Ellen Forty; Véronique Arnal; Conrad A Matthee

    2008-01-01

    BACKGROUND: The number of rodent clades identified above the family level is contentious, and to date, no consensus has been reached on the basal evolutionary relationships among all rodent families. Rodent suprafamilial phylogenetic relationships are investigated in the present study using ~7600 nucleotide characters derived from two mitochondrial genes (Cytochrome b and 12S rRNA), two nuclear exons (IRBP and vWF)

  8. Karyotype evolution and phylogenetic relationships of hamsters (Cricetidae, Muroidea, Rodentia) inferred from chromosomal painting and banding comparison

    Microsoft Academic Search

    Svetlana A. Romanenko; Vitaly T. Volobouev; Polina L. Perelman; Vladimir S. Lebedev; Natalya A. Serdukova; Vladimir A. Trifonov; Larisa S. Biltueva; Wenhui Nie; Patricia C. M. O’Brien; Nina Sh. Bulatova; Malcolm A. Ferguson-Smith; Fengtang Yang; Alexander S. Graphodatsky

    2007-01-01

    The evolutionary success of rodents of the superfamily Muroidea makes this taxon the most interesting for evolution studies,\\u000a including study at the chromosomal level. Chromosome-specific painting probes from the Chinese hamster and the Syrian (golden)\\u000a hamster were used to delimit homologous chromosomal segments among 15 hamster species from eight genera: Allocricetulus, Calomyscus, Cricetulus, Cricetus, Mesocricetus, Peromyscus, Phodopus and Tscherskia (Cricetidae,

  9. Phylogenetic relationship between Callosciurus caniceps andC. inornatus (Rodentia, Sciuridae): Implications for zoogeographical isolation by the Mekong River

    Microsoft Academic Search

    T. Oshida; C. N. Dang; S. T. Nguyen; N. X. Nguyen; H. Endo; J. Kimura; M. Sasaki; A. Hayashida; A. Takano; M. Yasuda; Y. Hayashi

    2011-01-01

    To test the riverine barrier hypothesis in small arboreal mammals, we examined phylogenetic relationship between two Callosciurus squirrel species (C. caniceps and C. inornatus) geographically isolated in the northeastern part of the Indochina Peninsula by the Mekong River. We did this by comparing complete mitochondrial DNA cytochrome b gene sequences of these two squirrels and five other Callosciurus species: C.

  10. Phylogenetic relationship between Callosciurus caniceps and C. inornatus (Rodentia, Sciuridae): Implications for zoogeographical isolation by the Mekong River

    Microsoft Academic Search

    Tatsuo Oshida; Can Ngoc Dang; Son Truong Nguyen; Nghia Xuan Nguyen; Hideki Endo; Junpei Kimura; Motoki Sasaki; Akiko Hayashida; Ai Takano; Masatoshi Yasuda; Yoshihiro Hayashi

    2011-01-01

    To test the riverine barrier hypothesis in small arboreal mammals, we examined phylogenetic relationship between two Callosciurus squirrel species (C. caniceps and C. inornatus) geographically isolated in the northeastern part of the Indochina Peninsula by the Mekong River. We did this by comparing complete mitochondrial DNA cytochrome b gene sequences of these two squirrels and five other Callosciurus species: C.

  11. Geographic variation in the white-throated woodrat, Neotoma albigula (Rodentia: Muridae) from New Mexico, Texas, and northern Mexico 

    E-print Network

    Rogers, Duke Sanford

    1979-01-01

    cranial measurements. Greatest length of skull, GLS, A-B; condylobasilar length, CBL, C-0; length of nasals, NL, A-E; length of rostrum, RL, A-F; rostral breadth, RB, G-H; zygomatic breadth, ZB, I-J; mastoid breadth, MB, K-L; least interorbital... vectors for females. See p. 26 for explanation of figure and Figure 2, page 9 for key to GLOC. 22 21 FEMALES 25 2. 0 0 55 55 ee 59 50 54 32 9 13 27 ee 2 35 2 1. 9 31 1. 8 0. 78 0. 72 0. 66 0. 60 Vector I 0. 54 0. 48 0. 42 36...

  12. Identification of crystalline allantoin in the urine of African Cricetidae (Rodentia) and its role in their water economy

    Microsoft Academic Search

    Rochelle Buffenstein; W. E. Campbell; J. U. M. Jarvis

    1985-01-01

    All eleven cricetid species, examined in this investigation, produced an off-white crystal-line precipitate in their urine when deprived of water, whereas not one murid examined did so. This crystalline compound was identified as allantoin, a common end product of purine catabolism. The quantity found in the solid precipitate alone accounted for 47% of the total nitrogen excreted and was approximately

  13. [Infection induced in wild rodents Dasyprocta leporina (Rodentia: Dasyproctidae), with larval eggs of Lagochilascaris minor (Nematoda: Ascarididae)].

    PubMed

    Volcán, G S; Medrano, C E

    1990-01-01

    Specimens of Dasyprocta leporina (Linnaeus, 1758) were raised out their natural environment. At three to four months of age they were orally inoculated with Lagochilascaris minor (Leiper, 1909) eggs obtained from a native patient. The eggs were incubated for more than 80 days so that it was possible to obtain, by mechanical compression, larvae that could be maintained alive in liquid medium for 48 hours or more. The animals were sacrificed 14-46 days after infection and tangled larva in inflammatory nodules were found in skeletal muscle without foreign body reaction, abscess formation or calcification. The development of the nodules did not seem to affect the hosts. The larvae obtained were similar to those described by SPRENT as the third stage of these helminths. When white mice were inoculated with similar material it was not possible to recuperate larva from their tissues nor were nodules found. Based on these results it is postulated that the helminth does not present a pulmonary cycle and that its development requires an intermediary host. PMID:2135484

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

    PubMed

    Izdebska, Joanna N; Rolbiecki, Leszek

    2015-01-01

    Demodex flagellurus Bukva, 1985 is one of two known demodecid mites of the house mouse Mus musculus Linnaeus, 1758, in which it is observed in genital area. Skin fragments of 30 house mice from various regions of Poland (residential buildings in Gdynia and Gda?sk, rural region in Wielkopolska-Kujawska Lowland) were examined. The mites were noted in 25.0% of the mice, with mean intensity of 48.0 and intensity range of 2-103. D. flagellurus demonstrated the differentiated occurrence in host populations. PMID:25911036

  15. The oldest South American tuco-tuco (late Pliocene, northwestern Argentina) and the boundaries of the genus Ctenomys (Rodentia, Ctenomyidae)

    Microsoft Academic Search

    Diego H. Verzi; A. Itatí Olivares; Cecilia C. Morgan

    2010-01-01

    A new species of Ctenomyidae from the late Pliocene of Uquía Formation (northwestern Argentina) is described. The new remains consist of a fragmentary rostrum, and a left mandible with partial lower dentition. Its phylogenetic affinity and morphological specializations for tooth-digging support its assignation to the South American rodent genus Ctenomys. In this context, we highlight the importance of unique morphological

  16. Ecological and histological aspects of tail loss in spiny mice (Rodentia: Muridae, Acomys) with a review of its occurrence

    E-print Network

    Dayan, Tamar

    revealed a plane separating the skin layer from the underlying muscles and vertebrae, facilitating loss of the skin with little bleeding. The remainder (muscles and bone) is later chewed off by the mouse. A survey invertebrates and vertebrates. It is often con- sidered an anti-predatory defence mechanism (e.g., Robinson

  17. Pyriproxyfen bait for control of plague vector fleas (Siphonaptera:Ceratophyllidae) on rock squirrels (Rodentia:Sciuridae) 

    E-print Network

    Dietrich, Erin Bess Gabrielle

    2001-01-01

    grasses such as wild rye (Elymus spp. ), acorns of shrub live oak (guercus rurbinella), flesh of a western diamond rattlesnake (Crotalur atrox), and such things as bread crusts, potato chips and Iruit left by hikers. Squirrels also feed on cottonwood... and inspiring. Thank you Dr. Betsy Browder for your aid in filing my TAMU Animal Use Protocol and helping me through all the 'red tape'. Evelyn Celli, Carol Stevens and Denise Sofranko (USDA, APHIS, Animal Care, Western Region), thank you for knowing me...

  18. Revision of the Wind River faunas, early Eocene of central Wyoming. IX - The oldest known hystricomorphous rodent (Mammalia: Rodentia)

    NASA Technical Reports Server (NTRS)

    Dawson, Mary R.; Krishtalka, Leonard; Stucky, Richard K.

    1990-01-01

    The rostral portion of the skull of a new genus and species of rodent, Armintomys tullbergi, from the earliest middle Eocene of the Wind River Basin (Wyoming) provides the geologically oldest known record of the hystricomorphous zygomasseteric structure. Armintomys also preserves the oldest known occurrence of incisor enamel that is transitional from pauciserial to uniserial. Other dental characters include: anteriorly grooved incisor, small premolars, and relatively primitive sciuravidlike molars. Analysis of this unique combination of characters implies that Armintomys is the oldest known myomorph rodent and the only known representative of a new family. Armintomyidae, which is referred, with question, to the myomorph superfamily Dipodoidea. Armintomys is more primitive, especially in premolar retention and structure, than the Bridgerian zapodid Elymys from Nevada, but adds to evidence from the latter for an early origin and radiation of dipodoid rodents.

  19. Genetic Pool Information Reflects Highly Suitable Areas: The Case of Two Parapatric Endangered Species of Tuco-tucos (Rodentia: Ctenomiydae)

    PubMed Central

    Galiano, Daniel; Bernardo-Silva, Jorge; de Freitas, Thales R. O.

    2014-01-01

    Conservation of small mammals requires knowledge of the genetically and ecologically meaningful spatial scales at which species respond to habitat modifications. Conservation strategies can be improved through the use of ecological niche models and genetic data to classify areas of high environmental suitability. In this study, we applied a Maxent model integrated with genetic information (nucleotide diversity, haplotype diversity and Fu's Fs neutrality tests) to evaluate potential genetic pool populations with highly suitable areas for two parapatric endangered species of tuco-tucos (Ctenomys minutus and C. lami). Our results demonstrated that both species were largely influenced by vegetation and soil variables at a landscape scale and inhabit a highly specific niche. Ctenomys minutus was also influenced by the variable altitude; the species was associated with low altitudes (sea level). Our model of genetic data associated with environmental suitability indicate that the genetic pool data were associated with highly suitable areas for C. minutus. This pattern was not evident for C. lami, but this outcome could be a consequence of the restricted range of the species. The preservation of species requires not only detailed knowledge of their natural history and genetic structure but also information on the availability of suitable areas where species can survive, and such knowledge can aid significantly in conservation planning. This finding reinforces the use of these two techniques for planning conservation actions. PMID:24819251

  20. The role of vibrissal sensing in forelimb position control during travelling locomotion in the rat (Rattus norvegicus, Rodentia).

    PubMed

    Niederschuh, Sandra J; Witte, Hartmut; Schmidt, Manuela

    2015-02-01

    In the stem lineage of therians, a comprehensive reorganization of limb and body mechanics took place to provide dynamic stability for rapid locomotion in a highly structured environment. At what was probably the same time, mammals developed an active sense of touch in the form of movable mystacial vibrissae. The rhythmic movements of the limbs and vibrissae are controlled by central pattern-generating networks which might interact with each other in sensorimotor control. To test this possible interaction, we studied covariation between the two by investigating speed-dependent adjustments in temporal and spatial parameters of forelimb and vibrissal kinematics in the rat. Furthermore, the possible role of carpal vibrissae in connecting the two oscillating systems was explored. We compared locomotion on continuous and discontinuous substrates in the presence and absence of the mystacial or/and carpal vibrissae across a speed range of 0.2-0.5m/s and found that a close coupling of the kinematics of the two oscillating systems appears to be precluded by their differential dependence on the animal's speed. Speed-related changes in forelimb kinematics mainly occur in temporal parameters, whereas vibrissae change their spatial excursion. However, whisking frequency is always high enough that at least one whisk cycle falls into the swing phase of the limb, which is the maximum critical period for sensing the substrate on which the forepaw will be placed. The influence of tactile cues on forelimb positional control is more subtle than expected. Tactile cues appear to affect the degree of parameter variation but not average parameters or the failure rate of limbs during walking on a perforated treadmill. The carpal vibrissae appear to play a role in sensing the animal's speed by measuring the duration of the stance phase. The absence of this cue significantly reduces speed-related variation in stride frequency and vibrissal protraction. PMID:25547567

  1. Geographic variation in the white-throated woodrat, Neotoma albigula (Rodentia: Muridae) from New Mexico, Texas, and northern Mexico

    E-print Network

    Rogers, Duke Sanford

    1979-01-01

    performed on cranial measurements of both sexes since males and females of this species were significantly s ily di phit. Th di ti t sub p i f N. ~)bi ~ 1 )N. ~lbi TN, N. a. sb 1, dN. a. i)ar gi*diuth region of study. N. a. melas and N. a. robusta, two.... robusta) was based largely on differences in color of pelage. Dice (1929) characterized N. a. melas as possessing dark, almost black upperparts, and gray to white underparts. No mention was made of any cranial differences. Blair (1939) distinguished...

  2. Mol. Biol. Evol. 19(7):10531065. 2002 2002 by the Society for Molecular Biology and Evolution. ISSN: 0737-4038

    E-print Network

    Huchon, Dorothée

    of Belfast, UK Rodentia is the largest order of placental mammals, with approximately 2,050 species divided into 28 families. It is also one of the most controversial with respect to its monophyly, relationships. The phylogenetic results significantly support rodent monophyly, the association of Rodentia with Lagomorpha (the

  3. Characterization of the Kidney Transcriptome of the Long-Haired Mouse Abrothrix hirta (Rodentia, Sigmodontinae) and Comparison with That of the Olive Mouse A. olivacea.

    PubMed

    Valdez, Lourdes; Giorello, Facundo; Feijoo, Matías; Opazo, Juan C; Lessa, Enrique P; Naya, Daniel E; D'Elía, Guillermo

    2015-01-01

    To understand how small mammals cope with the challenge of water homeostasis is a matter of interest for ecologists and evolutionary biologists. Here we take a step towards the understanding of the transcriptomic functional response of kidney using as a model the long-haired mouse (Abrothrix hirta) a species that distributes across Patagonian steppes and Austral temperate rainforests in Argentina and Chile. Specifically, we i) characterize the renal transcriptome of A. hirta, and ii) compare it with that-already available-of the co-generic and co-distributed A. olivacea. Renal mRNA transcripts from 16 specimens of A. hirta from natural populations were analyzed. Over 500 million Illumina paired-end reads were assembled de novo under two approaches, an individual assembly for each specimen, and a single in-silico normalized joint assembly including all reads from all specimens. The total number of annotated genes was similar with both strategies: an average of 14,956 in individual assemblies and 14,410 in the joint assembly. Overall, 15,463 distinct genes express in the kidney of A. hirta. Transcriptomes of A. hirta and A. olivacea were similar in terms of gene abundance and composition: 95.6% of the genes of A. hirta were also found in A. olivacea making their functional profiles also similar. However, differences in the transcriptome of these two species were observed in the set of highly expressed genes, in terms of private genes for each species and the functional profiles of highly expressed genes. As part of the novel transcriptome characterization, we provide distinct gene lists with their functional annotation that would constitute the basis for further research on these or any other species of the subfamily Sigmodontinae, which includes about 400 living species distributed from Tierra del Fuego to southern United States. PMID:25860131

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

    PubMed

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

    2014-01-01

    The expediency of a modular approach to estimating fluctuating asymmetry (FA) of complex morphological structures was shown using the mandible of the bank vole (Clethrionomys glareolus Schreber, 1780) as an example. FA of the shape of two mandibular regions (modules) defined developmentally and functionally, was assessed by means of geometric morphometrics. The differences between mandibular regions in the FA levels were found for both individual landmarks and integral indices of asymmetry. Regardless of age, gender or sampling year, FA estimates obtained for posterior region including part of the ramus and processes were higher than those for anterior region including the diastemal area. The results suggest that modularity of complex morphological structures should be taken into account when analyzing FA. PMID:25782276

  5. [Dynamics of chromosome variation in mole voles Ellobius tancrei (Mammalia, Rodentia) in Pamiro-Alai in the period from 1982 to 2008].

    PubMed

    Liapunova, E A; Baklushinskaia, I Iu; Saidov, A S; Saidov, K Kh

    2010-05-01

    Analysis of a new karyological material of mole voles Ellobius tancrei from a zone of high chromosome variation (Pamiro-Alai) in comparison with the data obtained 25 years ago showed a slight shift of the chromosome numbers on the western border of the Robertsonian fan due to the expansion of the area of forms with a low chromosome number. In the central part of the fan zone, the process of active hybridization of forms with different chromosome numbers, but not of the original forms, is still going on. Some problems of speciation on the basis of Robertsonian translocations are discussed. PMID:20583600

  6. [Experimental hybridization of voies of the genus Microtus s.l. M. socialis with species of the group arvalis (Mammalia, Rodentia)].

    PubMed

    Koval'skaia, Iu M; Savinetskaia, L E; Aksenova, T G

    2014-01-01

    The results of interspecific crosses of the social vole Microtus socialis with the Altai vole M. obscurus, the East European vole M. rossiaemeridionalis, and the Transcaspian vole M. transcaspicus are presented. The role of the sperm head structure in the reproductive isolation of this species was studied. Hybrids were obtained in five of the six crossing combinations. It is established that significant differences in the sperm head shape in the social vole and in arvalis group species do not prevent fertilization. The sterility of hybrids indicates the existence of postcopulative mechanisms of reproductive isolation. PMID:25739313

  7. Genome analysis of ground squirrels of the genus Citellus (Rodentia, Sciuridae) I. DNA reassociation kinetics and genome size of eight species

    Microsoft Academic Search

    L. K. Ginatulina; A. A. Ginatulin; E. A. Lvapunova; N. N. Vorontsov

    1982-01-01

    Kinetic of reassociation of short DNA fragments were measured in eight ground squirrel species: Citellus undulatus, C. parryi, C. relictus, C. dauricus, C. citellus, C. pygmaeus, C. fulvus and C. major. It was shown that 30–50% of their genome were represented by repeated sequences forming three kinetic fractions, i.e., very fast (Cot<10-3), fast (Cot 10-3-3×10-1) and intermediate (Cot 6×10-1-6×101). Based

  8. The evolution of nuclear microsatellite DNA markers and their flanking regions using reciprocal comparisons within the African mole-rats (Rodentia: Bathyergidae)

    E-print Network

    Ingram, Colleen Marie

    2006-10-30

    and fauna since the Miocene. Second, as with other fossorial rodents such as Ctenomys in South America, Thomomys and Geomys in North America, and Spalax in the eastern Mediterranean, patterns of morphological and genetic variation in Cryptomys make...

  9. Echinococcus vogeli Rausch and Bernstein, 1972, from the paca, Cuniculus paca L. (Rodentia: Dasyproctidae), in the Departamento de Santa Cruz, Bolivia.

    PubMed

    Gardner, S L; Rausch, R L; Camacho, O C

    1988-06-01

    Among approximately 2,000 mammals examined for helminths in various regions of Bolivia during 1983-1987, cysts of Echinococcus vogeli Rausch and Bernstein, 1972, were found in a single paca, Cuniculus paca L., collected at La Laguna, Departamento de Santa Cruz (lat. 16 degrees 36'W; long. 62 degrees 42'S). This record, the first from Bolivia, represents a considerable extension of the known geographic range of this species in South America. Upon analysis of the morphologic characteristics of the protoscoleces derived from the cysts, the sizes of rostellar hooks from the material from the paca were found to be well within the ranges reported in previous studies. Statistical analysis of frequency distributions of hook characteristics revealed some deviations from normality. These results indicate that parametric statistics should be applied with caution in analyses of inter-and intraspecific variation of morphologic characteristics of hooks of metacestodes of the genus Echinococcus. PMID:3379522

  10. A new species of Aplodontopus (Acari: Astigmata: Chortoglyphidae) from the yellow-bellied marmot, Marmota flaviventris (Rodentia: Sciuridae) in Eastern Washington, USA, with observations on its pathology

    Microsoft Academic Search

    Gerald W. Krantz; Barry M. OConnor; William J. Foreyt; Alex Fain

    2003-01-01

    The deutonymph of a new species of the chortoglyphid genus Aplodontopus is described from a population of Marmota flaviventris occupying a city park in eastern Washington state, USA. Many of the mite-infested individuals displayed hair loss ranging from 20–100%, along with a variety of tissue and histological abnormalities. A key to the deutonymphs of described species of Aplodontopus is presented.

  11. Morphometric analysis of the placenta in the New World mouse Necromys lasiurus (Rodentia, Cricetidae): a comparison of placental development in cricetids and murids

    PubMed Central

    2013-01-01

    Background Stereology is an established method to extrapolate three-dimensional quantities from two-dimensional images. It was applied to placentation in the mouse, but not yet for other rodents. Herein, we provide the first study on quantitative placental development in a sigmodontine rodent species with relatively similar gestational time. Placental structure was also compared to the mouse, in order to evaluate similarities and differences in developmental patterns at the end of gestation. Methods Fetal and placental tissues of Necromys lasiurus were collected and weighed at 3 different stages of gestation (early, mid and late gestation) for placental stereology. The total and relative volumes of placenta and of its main layers were investigated. Volume fractions of labyrinth components were quantified by the One Stop method in 31 placentae collected from different individuals, using the Mercator® software. Data generated at the end of gestation from N. lasiurus placentae were compared to those of Mus musculus domesticus obtained at the same stage. Results A significant increase in the total absolute volumes of the placenta and its main layers occurred from early to mid-gestation, followed by a reduction near term, with the labyrinth layer becoming the most prominent area. Moreover, at the end of gestation, the total volume of the mouse placenta was significantly increased compared to that of N. lasiurus although the proportions of the labyrinth layer and junctional zones were similar. Analysis of the volume fractions of the components in the labyrinth indicated a significant increase in fetal vessels and sinusoidal giant cells, a decrease in labyrinthine trophoblast whereas the proportion of maternal blood space remained stable in the course of gestation. On the other hand, in the mouse, volume fractions of fetal vessels and sinusoidal giant cells decreased whereas the volume fraction of labyrinthine trophoblast increased compared to N. lasiurus placenta. Conclusions Placental development differed between N. lasiurus and M. musculus domesticus. In particular, the low placental efficiency in N. lasiurus seemed to induce morphological optimization of fetomaternal exchanges. In conclusion, despite similar structural aspects of placentation in these species, the quantitative dynamics showed important differences. PMID:23433040

  12. First Report on Isolation and Characterization of Leishmania major from Meriones hurrianae (Rodentia: Gerbillidae) of A Rural Cutaneous leishmaniasis Focus in South-Eastern Iran

    PubMed Central

    Kassiri, Hamid; Naddaf, Saied Reza; Javadian, Ezat–Aldin; Mohebali, Mehdi

    2013-01-01

    Background Zoonotic Cutaneous Leishmaniasis (ZCL) is an endemic health problem in many rural areas of Iran, with doubled number of incidences over the last decade. Different species of rodents serve as natural reservoir host for ZCL. The disease is considered as a major health problem in rural areas of Mirjaveh, Chabahar, and Konarak Counties of Sistan va Baluchistan Province. Objectives This study describes the identity of Leishmania species, isolated from Meriones hurrianae from Chabahar County using RAPD-PCR methodology. Materials and Methods Rodents were entrapped by live traps baited with roasted walnut, tomato, and cucumber during spring and summer. All rodents were identified based on external features including fur color, ears characteristics, tail length, hind feet, body measurements, and internal features of teeth and cranium. Giemsa-stained impressions from rodents’ ears were examined for amastigotes microscopically. The samples from infected rodents were cultured in NNN+LIT medium and then the harvested parasites at the stationary phase were subjected to DNA extraction followed by amplification with RAPD-PCR. Results All the 28 entrapped animals were identified as M. hurrianae. Five animals showed to harbor Leishmania parasite by microscopy. Leishmania DNA isolated from five M. hurrianae produced distinctive bands of L. major with four primers. However, the products that were amplified with primers AB1-07, 327, and 329 were stable and reproducible. This is the first report on the isolation and identification of L. major from M. hurrianae from Iran. Conclusions Regarding infection rate of 17.8%, M. hurrianae seems to play the major role in the maintenance and transmission of disease to humans in this area. PMID:24616787

  13. The evolution of nuclear microsatellite DNA markers and their flanking regions using reciprocal comparisons within the African mole-rats (Rodentia: Bathyergidae) 

    E-print Network

    Ingram, Colleen Marie

    2006-10-30

    al., 1995; Zhu et al., 2000). Recently the utility of microsatellites as phylogenetic markers has been assessed 8 8 (Ar?valo et al., 2004; Jin et al., 1996; Ort? et al., 1997; Schl?tterer, 2001; Zardoya et al., 1996). The results were mixed...

  14. Isolation of 18 polymorphic microsatellite loci from the North American red squirrel, Tamiasciurus hudsonicus (Sciuridae, Rodentia), and their cross-utility in other species

    Microsoft Academic Search

    MELISSA R. GUNN; DEBORAH A. DAWSON; ANDREW LEVISTON; KATIE HARTNUP; COREY S. DAVIS; CURTIS STROBECK; JON SLATE; DAVID W. COLTMAN

    2005-01-01

    We isolated 18 polymorphic microsatellite loci to be used for pedigree analysis in a wild population of North American red squirrels, Tamiasciurus hudsonicus . Allelic diversity and observed heterozygosity ranged from six to 13 and 0.39 to 0.89, respectively, in a sample of 93 individuals. Up to 13 sets of primers also amplify in other rodent species.

  15. Comparative chromosome mapping of the rRNA genes and telomeric repeats in three Italian pine voles of the Microtus savii s.l. complex (Rodentia, Cricetidae)

    PubMed Central

    Gornung, Ekaterina; Bezerra, Alexandra M. R.; Castiglia, Riccardo

    2011-01-01

    Abstract The Microtus (Terricola) savii s. l. complex is a group of five species/subspecies of the Italian pine voles, which diverged at different times either with or without chromosomal differentiation. The evidence of chromosomal diversification has so far concerned the shape of the sex chromosomes, especially the X chromosome. Three taxa of the group, Microtus savii savii, Microtus savii nebrodensis, and Microtus savii tolfetanus have identical karyotypes with metacentric X chromosomes. The X chromosomes of Microtus brachycercus and Microtus brachycercus niethammericus are, respectively, subtelocentric and acrocentric in shape. The Microtus savii complex has been long an object of conventional karyological studies, but comparative molecular cytogenetic data were completely missing. Therefore, we conducted a comparative chromosomal mapping of rRNA genes (rDNA) and telomeric repeats in three of the five taxa of the group: Microtus savii savii, Microtus savii nebrodensis, and Microtus brachycercus niethammericus, each of which belongs to a distinct mitochondrial clade.The survey revealed that differentiation of the clades was accompanied by remarkable changes with regard to the number and locations of the rDNA sites. Thus, Microtus savii savii and Microtus savii nebrodensis have especially high numbers of rDNA sites, which are located in the centromeric regions of, correspondingly, 18 and 13 chromosome pairs, whereas Microtus brachycercus niethammericus shows variable (8–10) and heteromorphic rDNA sites on both centromeric and telomeric regions. Interstitial telomeric sites (ITS), which are believed to indicate possible breakpoints of recurring chromosomal rearrangements, are present on the largest biarmed chromosomes and on the metacentric X chromosomes in Microtus savii savii and Microtus savii nebrodensis. These preliminary results are discussed in the context of recent advances in phylogeny of the group, as well as the rDNA genomic organization and X chromosome rearrangements in the genus Microtus. PMID:24260633

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

    PubMed

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

    2014-12-01

    Land use changes by human activities have been the main causes of habitats and wildlife population degradation. In the Tehuantepec Isthmus in Oaxaca, the tropical habitat of the porcupine Sphiggurus mexicanus has been subject to vegetation and land use changes, causing its reduction and fragmentation. In this study, we estimated vegetation cover and land use (?n) change rates and assessed habitat availability and potential cor- ridors for possible porcupine movements to avoid its isolation. In the study area, the type of vegetation with the most change rate value was the savanna (?n = -2.9), transformed into induced grasslands. Additionally, we have observed the porcupine (since 2011) in semi-deciduous (?n = -0.87) and tropical dry (?n = -0.89) forests that have been transformed in temporal agriculture and mesquite and induced grasslands. The vegetation inhabited by the porcupine resulted in recording a total of 64 plant species (44 trees, nine vines, seven herbs, four shrubs), of which the vine Bunchosia lanceolata showed the highest importance value (41.85) followed by the trees Guazuma ulmifolia (22.71), Dalbergia glabra (18.05), and Enterolobium cyclocarpum (17.02). The habitat evaluation and potential corridor analysis showed that only 1 501.93ha could be considered as suitable habitats with optimum structural conditions (coverage, surface, and distances to transformed areas) to maintain viable populations of S. mexicanus, and 293.6 ha as corridors. An increasing destruction of the porcupines' habitat has been observed in the study area due to excessive logging, and actions for this species and its habitat conserva- tion and management have to be taken urgently. PMID:25720182

  17. Geographic variation in morphological traits of the large Japanese field mouse, Apodemus speciosus (Rodentia, Muridae), from the Izu Island Group, Japan.

    PubMed

    Kageyama, Mariko; Motokawa, Masaharu; Hikida, Tsutomu

    2009-04-01

    We investigated geographic variation in morphological traits of the large Japanese field mouse (Apodemus speciosus) from the Izu Island Group, Japan. There was sexual dimorphism in external characters and cranial measurements; hence, these were considered in subsequent analyses. There was geographic divergence in morphometric characters among populations of the Izu Island Group and Honshu. Mice from the Miyakejima Island and Niijima-Shikinejima Islands differed from those of other populations and from each other; Oshima Island mice also differed, but to a lesser degree. Mice from three populations from Honshu were similar to one another, and mice from Kozushima Island were more similar to those from Honshu populations than those from Izu Island Group populations. These results suggest that A. speciosus populations in the Izu Island Group may have had multiple origins. One possible hypothesis to explain these patterns of variation is that the Miyakejima, Niijima, and Shikinejima populations may share a relatively longer history of overseas dispersal, whereas the Kozushima populations may have experienced a recent invasion from Honshu via human activities. PMID:19798920

  18. Ctenomys lami : The highest chromosome variability in Ctenomys (Rodentia, Ctenomyidae) due to a centric fusion\\/fission and pericentric inversion system

    Microsoft Academic Search

    Thales Renato O. de Freitas

    2007-01-01

    Ctenomys lami Freitas, 2001 is an endemic species of rodent inhabiting the Coastal Plain of southern Brazil, along a narrow line of old\\u000a dunes formed in the Pleistocene. This species has five different diploid numbers (2n=54, 55a, 55b, 56a, 56b, 57 and 58) and\\u000a ten different autosomal fundamental numbers (FNa=74, 75, 76, 77, 78, 79, 80, 81, 82, and 84).

  19. Extensive mtDNA variation within the yellow-pine chipmunk, Tamias amoenus (Rodentia: Sciuridae), and phylogeographic inferences for northwest North America.

    PubMed

    Demboski, John R; Sullivan, Jack

    2003-03-01

    The yellow-pine chipmunk, Tamias amoenus, is common in xerophytic forests throughout much of northwest North America. We analyzed cytochrome b sequence variation from 155 individuals representing 57 localities across the distribution of T. amoenus including 10 additional species of Tamias. Maximum likelihood and parsimony tree estimation methods were used in conjunction with nested clade analysis to infer both deep and population-level processes. Our results indicate that two currently recognized subspecies of T. amoenus (T. a. canicaudus and T. a. cratericus) are not nested within other samples of T. amoenus. Maximum uncorrected levels of intraspecific sequence divergence within remaining samples of T. amoenus are >7%. Substantial geographic variation is characterized by 12 well-supported clades that correspond to distinct mountain ranges, but do not necessarily follow existing subspecific taxonomy. Significant association between geography and genealogy was detected within many of these clades and can be attributed to different population-level processes including past fragmentation, recent range expansion, and isolation by distance. PMID:12644399

  20. Stratigraphic context and paleoenvironmental significance of minor taxa (Pisces, Reptilia, Aves, Rodentia) from the late Early Pleistocene paleoanthropological site of Buia (Eritrea).

    PubMed

    Rook, L; Ghinassi, M; Carnevale, G; Delfino, M; Pavia, M; Bondioli, L; Candilio, F; Coppa, A; Martínez-Navarro, B; Medin, T; Papini, M; Zanolli, C; Libsekal, Y

    2013-01-01

    The Buia Homo site, also known as Wadi Aalad, is an East African paleoanthropological site near the village of Buia that, due to its very rich yield from the late Early Pleistocene, has been intensively investigated since 1994. In this paper, which reports on the finds of the 2010-2011 excavations, we include new fossil evidence on previously identified taxa (i.e., reptiles), as well as the very first description of the small mammal, fish and bird remains discovered. In particular, this study documents the discovery of the first African fossil of the genus Burhinus (Aves, Charadriiformes) and of the first rodent from the site. This latter is identified as a thryonomyid rodent (cane rat), a relatively common taxon in African paleoanthropological faunal assemblages. On the whole, the new occurrences documented within the Buia vertebrate assemblage confirm the occurrence of taxa characterized by strong water dependence. The paleoenvironmental characteristics of the fauna are confirmed as fully compatible with the evidence obtained through sedimentology and facies analysis, documenting the sedimentary evolution of fluvio-deltaic and lacustrine systems. PMID:23159190

  1. Coccidian parasites (Apicomplexa: Eimeriidae) of Microtus spp. (Rodentia: Arvicolidae) from the United States, Mexico, and Japan, with descriptions of five new species.

    PubMed

    Vance, T L; Duszynski, D W

    1985-06-01

    Beginning in July 1980, 149 voles (Microtus spp.) representing 9 species and 14 subspecies collected in Japan, Mexico and the United States were examined for coccidia; 67 (45%) had oocysts in their feces. These included 1 of 3 (33%) M. californicus sactidiegi; 0 of 1 M. longicaudus longicaudus; 0 of 1 M. l. macrurus; 48 of 111 (43%) M. mexicanus including 11 of 26 (42%) M. m. fulviventer, 1 of 2 (50%) M. m. fundatus, 13 of 31 (42%) M. m. mexicanus, 1 of 4 (25%) M. m. mogollonensis and 22 of 48 (46%) M. m. subsimus; 5 of 8 (63%) M. montanus arizonensis; 6 of 6 M. montebelli montebelli; 2 of 4 (50%) M. oregoni oregoni; 5 of 13 (38%) M. pennsylvanicus pennsylvanicus; 0 of 1 M. quasiater and 0 of 1 M. townsendii townsendii. The following coccidians were identified from infected voles: Eimeria saxei n. sp. (syn. E. wenrichi "B") from M. c. sactidiegi; E. ochrogasteri, E. saxei, E. wenrichi (syn. E. wenrichi "A"), and Eimeria sp. from M. m. fulviventer, Eimeria sp. from M. m. fundatus; E. ochrogasteri, E. saxei, Eimeria tolucadensis n. sp., E. wenrichi, and Eimeria sp. from M. m. mexicanus; E. wenrichi from M. m. mogollonensis; Eimeria coahuiliensis n. sp., E. saxei, Eimeria subsimi n. sp., E. wenrichi, Eimeria sp., and Isospora mexicanasubsimi n. sp. from M. m. subsimus; E. tamiasciuri and E. wenrichi from M. m. arizonensis; Eimeria spp. from M. m. montebelli; E. saxei and E. wenrichi from M. o. oregoni; and E. ochrogasteri and E. wenrichi from M. p. pennsylvanicus. Sporulated oocytsts of Eimeria coahuiliensis n. sp. were ellipsoid, 29.6 X 19.6 (27-34 X 18-22) micron with ovoid sporocysts 14.4 X 8.9 (13-18 X 8-10) microns. Sporulated oocysts of Eimeria saxei n. sp. were subspheroid, 13.0 X 11.0 (11-14 X 10-12) micron with ovoid sporocysts 7.5 X 4.0 (6-9 X 4-5) micron. Sporulated oocysts of Eimeria subsimi n. sp. were ovoid/subspheroid, 25.1 X 18.7 (22-28 X 17-21) micron with ellipsoid sporocysts 13.9 X 7.4 (13-15 X 6-8) micron. Sporulated oocysts of Eimeria tolucadensis n. sp. were subspheroid, 25.4 X 20.3 (23-26 X 19-23) micron with ellipsoid sporocysts 11.3 X 7.8 (10-13 X 7-9) micron. Sporulated oocysts of Isospora mexicanasubsimi n. sp. were subspheroid, 23.7 X 23.1 (21-26 X 21-26) micron with ovoid sporocysts 14.9 X 10.8 (12-16 X 10-12) micron.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3891951

  2. Effects of pyriproxyfen spray, powder, and oral bait treatments on the relative abundance of nontarget arthropods of black-tailed prairie dog (Rodentia: Sciuridae) towns.

    PubMed

    Karhu, R R; Anderson, S H

    2000-07-01

    Separate black-tailed prairie dog, Cynomys ludovicianus (Ord), towns on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were treated with technical pyriproxyfen (Nylar) spray, powder, and oral bait. The treatments were applied to reduce relative abundance of the plague vector Oropsylla hirsuta (Baker). Because pyriproxyfen is a juvenile hormone analog, we were also concerned with the effects of the treatments on nontarget arthropods, which is the focus of this study. Pitfall traps and sweep net sampling were used to measure relative abundance of arthropod populations pre- and posttreatment. Nontarget arthropod sampling produced a large number of statistical comparisons that indicated significant declines (P < 0.05) in relative arthropod abundance. Many of the significant declines were probably because of natural fluctuations in arthropod populations rather than treatment effects. Because arthropod populations appeared to fluctuate randomly, we only made inferences about highly significant (P < 0.001) declines. In doing so, we hoped to abate some of the confusion created by the natural fluctuation in arthropod abundance and increase our chance of correctly attributing a population reduction to a treatment effect. Only Homoptera at the pyriproxyfen powder site exhibited highly significant reductions that appeared to be attributed to the treatments. Pyriproxyfen spray treatments did not significantly reduce relative arthropod abundance. PMID:10916304

  3. Effects of pyriproxyfen spray, powder, and oral bait treatments on the relative abundance of fleas (Siphonaptera: Ceratophyllidae) in black-tailed prairie dog (Rodentia: Sciuridae) towns.

    PubMed

    Karhu, R; Anderson, S

    2000-11-01

    Separate black-tailed prairie dog, Cynomys ludovicianus (Ord), towns on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were treated with technical pyriproxyfen (Nylar) using spray, powder, and oral bait carriers. Direct combing methods (1997 and 1998) and burrow flagging (1998) were used to estimate relative abundance of the plague vector Oropsylla hirsuta (Baker). Pyriproxyfen spray (0.05%) and powder (0.05%) did not significantly reduce (P > 0.05) O. hirsuta abundance. Pyriproxyfen bait, when applied every 4 wk at a concentration of 286 mg/50 g bait, significantly reduced (P < or = 0.05) O. hirsuta infesting prairie dogs, 4 mo after initial treatment. However, flea populations had recovered to pretreatment levels by the following summer (July 1999). PMID:11126542

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

    USGS Publications Warehouse

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

    2009-01-01

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

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

    PubMed

    Pelz-Serrano, Karla; Munguia-Vega, Adrian; Piaggio, Antoinette J; Neubaum, Melissa; Munclinger, Pavel; Pártl, Adam; VAN Riper Iii, Charles; Culver, Melanie

    2009-03-01

    We developed nine new nuclear dinucleotide microsatellite loci for Castor canadensis. All loci were polymorphic, except for one. The number of alleles ranged from two to four and from five to 12 in populations from Arizona and Wisconsin, respectively. Average heterozygosity ranged from 0.13 to 0.86 per locus. Since cross-species amplification in Castor fiber was successful only in four loci, we tested also nine recently published C. canadensis loci in the Eurasian species. Eight of the published loci amplified; however, three were monomorphic. The number of alleles was lower in C. fiber than in C. canadensis at all loci tested. PMID:21564690

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

    PubMed Central

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

    2013-01-01

    Identifying factors and the extent of their roles in the differentiation of populations is of great importance for understanding the evolutionary process in which a species is involved. Ctenomys minutus is a highly karyotype–polymorphic subterranean rodent, with diploid numbers ranging from 42 to 50 and autosomal arm numbers (ANs) ranging from 68 to 80, comprising a total of 45 karyotypes described so far. This species inhabits the southern Brazilian coastal plain, which has a complex geological history, with several potential geographical barriers acting on different time scales. We assessed the geographical genetic structure of C. minutus, examining 340 individuals over the entire distributional range and using information from chromosomal rearrangements, mitochondrial DNA (mtDNA) sequences and 14 microsatellite loci. The mtDNA results revealed seven main haplogroups, with the most recent common ancestors dating from the Pleistocene, whereas clustering methods defined 12 populations. Some boundaries of mtDNA haplogroups and population clusters can be associated with potential geographical barriers to gene flow. The isolation-by-distance pattern also has an important role in fine-scale genetic differentiation, which is strengthened by the narrowness of the coastal plain and by common features of subterranean rodents (that is, small fragmented populations and low dispersal rates), which limit gene flow among populations. A step-by-step mechanism of chromosomal evolution can be suggested for this species, mainly associated with the metapopulation structure, genetic drift and the geographical features of the southern Brazilian coastal plain. However, chromosomal variations have no or very little role in the diversification of C. minutus populations. PMID:23759727

  7. New karyotypes and some considerations about the chromosomal diversification of Ctenomys minutus (Rodentia: Ctenomyidae) on the coastal plain of the Brazilian state of Rio Grande do Sul.

    PubMed

    Freygang, Cristina Claumann; Marinho, Jorge Reppold; de Freitas, Thales R O

    2004-06-01

    The dominant mammals occupying the subterranean niche in South America are rodents of the genus Ctenomys, which form a large group of 56 species with chromosome numbers ranging from 2n = 10 to 70. In southern Brazil, Ctenomys minutus is the species with the widest geographic distribution, inhabiting sandy fields and dunes extending from Jaguaruna beach in the state of Santa Catarina to the town of São José do Norte in the state of Rio Grande do Sul. Eleven karyotypes (2n = 42; 2n = 46a; 2n = 46b; 2n = 47a; 2n = 47b; 2n = 48a; 2n = 48b; 2n = 49a; 2n = 49b; 2n = 50a and 2n = 50b) were described for this species and zones of hybridization are also known. A sample of 51 C. minutus specimens was collected from five sampling sites about 20km apart along the coastal plain of Rio Grande do Sul between the municipalities of Tavares (31 degrees 23'S 51 degrees 09'W) and São José do Norte (31 degrees 52'S 51 degrees 54'W). We were able to extend the known geographic distribution of C. minutus by 90 km, from Tavares southwards to São José do Norte. During our study we found five karyotypes (2n = 46b, 47b, 48b, 49b and 50b), four of which (2n = 47b, 48b, 49b and 50b) have not previously been described for this species. PMID:15330112

  8. Extensive mtDNA variation within the yellow-pine chipmunk, Tamias amoenus (Rodentia: Sciuridae), and phylogeographic inferences for northwest North America

    Microsoft Academic Search

    John R. Demboski; Jack Sullivan

    2003-01-01

    The yellow-pine chipmunk, Tamias amoenus, is common in xerophytic forests throughout much of northwest North America. We analyzed cytochrome b sequence variation from 155 individuals representing 57 localities across the distribution of T. amoenus including 10 additional species of Tamias. Maximum likelihood and parsimony tree estimation methods were used in conjunction with nested clade analysis to infer both deep and

  9. Vertebrate metacommunity structure along an extensive elevational gradient

    E-print Network

    Willig, Michael

    RESEARCH PAPER Vertebrate metacommunity structure along an extensive elevational gradient of three vertebrate orders (Chiroptera, Rodentia and Passeriformes) along an extensive elevational gradient. Using elevation as a proxy for variation in abiotic characteristics and the known elevational

  10. Two new species of Gliricola (Phthiraptera: Gyropidae) from the spiny tree rat, Mesomys hispidus, in Peru.

    E-print Network

    Price, Roger D.; Timm, Robert M.

    1993-06-01

    Two new species of Gliricola, G. woodmani and G. halli (Phthiraptera: Gyropidae), are described and illustrated for specimens from the spiny tree rat, Mesomys hispidus (Rodentia: Echimyidae), in Peru. Resumen--Se describe e ilustra dos nuevas...

  11. A taxonomic study of the Siphonaptera, or, fleas of Texas and an evaluation of their importance to public health

    E-print Network

    Eads, Richard Bailey

    1949-01-01

    ilineatus, variegatus and washingtoni; and in fleas infesting 3 other species, douglasii, idahoensis and lateralis. Specimens of 7 other genera of Rodentia have been found infected: Prairie dog (Cynomys); kangaroo rat (Dipodomys); marmot (i...

  12. Fossil and molecular evidence constrain scenarios for the early evolutionary and biogeographic history of hystricognathous rodents.

    PubMed

    Sallam, Hesham M; Seiffert, Erik R; Steiper, Michael E; Simons, Elwyn L

    2009-09-29

    The early evolutionary and paleobiogeographic history of the diverse rodent clade Hystricognathi, which contains Hystricidae (Old World porcupines), Caviomorpha (the endemic South American rodents), and African Phiomorpha (cane rats, dassie rats, and blesmols) is of great interest to students of mammalian evolution, but remains poorly understood because of a poor early fossil record. Here we describe the oldest well-dated hystricognathous rodents from an earliest late Eocene (approximately 37 Ma) fossil locality in the Fayum Depression of northern Egypt. These taxa exhibit a combination of primitive and derived features, the former shared with Asian "baluchimyine" rodents, and the latter shared with Oligocene phiomorphs and caviomorphs. Phylogenetic analysis incorporating morphological, temporal, geographic, and molecular information places the new taxa as successive sister groups of crown Hystricognathi, and supports an Asian origin for stem Hystricognathi and an Afro-Arabian origin for crown Hystricognathi, stem Hystricidae, and stem Caviomorpha. Molecular dating of early divergences within Hystricognathi, using a Bayesian "relaxed clock" approach and multiple fossil calibrations, suggests that the split between Hystricidae and the phiomorph-caviomorph clade occurred approximately 39 Ma, and that phiomorphs and caviomorphs diverged approximately 36 Ma. These results are remarkably congruent with our phylogenetic results and the fossil record of hystricognathous rodent evolution in Afro-Arabia and South America. PMID:19805363

  13. Testing Synchrony in Historical Biogeography: The Case of New World Primates and Hystricognathi Rodents

    PubMed Central

    Loss-Oliveira, Leticia; Aguiar, Barbara O.; Schrago, Carlos G.

    2012-01-01

    The abrupt appearance of primates and hystricognath rodents in early Oligocene deposits of South America has puzzled mastozoologists for decades. Based on the geoclimatic changes that occurred during the Eocene/Oligocene transition period that may have favoured their dispersal, researchers have proposed the hypothesis that these groups arrived in synchrony. Nevertheless, the hypothesis of synchronous origins of platyrrhine and caviomorph in South America has not been explicitly evaluated. Our aim in this work was to apply a formal test for synchronous divergence times to the Platyrrhini and Caviomorpha splits. We have examined a previous work on platyrrhine and hystricognath origins, applied the test to a case where synchrony is known to occur and conducted simulations to show that it is possible to formally test the age of synchronous nodes. We show that the absolute ages of Platyrrhini/Catarrhini and Caviomorpha/Phiomorpha splits depend on data partitioning and that the test applied consistently detected synchronous events when they were known to have happened. The hypothesis that the arrival of primates and hystricognaths to the New World consisted of a unique event cannot be rejected PMID:22346342

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

    PubMed

    Mello, Jhf; Moulton, T P; Raíces, Dsl; Bergallo, H G

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i) to calculate the carrying capacity K based on real data of the involved species and the environment; ii) propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii) determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present. PMID:25945639

  15. Airoldi, J.-P. (1978). Study through capture and recapture of a population of water voles, Arvicola terrestris scherman Shaw (Mammalia, Rodentia). Terre et Vie 32 : 3-45. (In French,

    E-print Network

    Airoldi, Jean-Pierre

    1978-01-01

    Airoldi, J.-P. (1978). Study through capture and recapture of a population of water voles, Arvicola-isolated population of the fossorial form of the Water vole, Arvicola terrestris scherman Shaw, was studied individuals. Water voles live generally in pairs. Outside the breeding period, they often live in more complex

  16. The laboratory rat strains most commonly used in research are believed to be domesticated albino strains of the Norway rat rattus nirvegicus. Rats like mice, belong to the order Rodentia

    E-print Network

    Shihadeh, Alan

    -Dawley, Wistar and Long- Evans. Sprague-Dawley and Wistar are albinos and the Long-Evans is a hooded rat. Several develop allergies to rat dander and urine proteins. Behavior Rats tend to be social animals and do well

  17. Hymenolepis folkertsi n. sp. (Eucestoda: Hymenolepididae) in the oldfield mouse Peromyscus polionotus (Wagner) (Rodentia: Cricetidae: Neotominae) from the southeastern Nearctic with comments on tapeworm faunal diversity among deer mice.

    PubMed

    Makarikov, Arseny A; Nims, Todd N; Galbreath, Kurt E; Hoberg, Eric P

    2015-06-01

    A previously unrecognized species of hymenolepidid cestode attributable to Hymenolepis is described based on specimens in Peromyscus polionotus, oldfield mouse, from Georgia near the southeastern coast of continental North America. Specimens of Hymenolepis folkertsi n. sp. differ from those attributed to most other species in the genus by having testes arranged in a triangle and a scolex with a prominent rostrum-like protrusion. The newly recognized species is further distinguished by the relative position and length of the cirrus sac, shape of seminal receptacle, and relative size of external seminal vesicle and seminal receptacle. Hymenolepidid cestodes have sporadically been reported among the highly diverse assemblage of Peromyscus which includes 56 distinct species in the Nearctic. Although the host genus has a great temporal duration and is endemic to the Nearctic, current evidence suggests that tapeworm faunal diversity reflects relatively recent assembly through bouts of host switching among other cricetid, murid, and geomyid rodents in sympatry. PMID:25762188

  18. Historical diversification of a terra-firme forest bird superspecies: a phylogeographic perspective on the role of different hypotheses of Amazonian diversification.

    PubMed

    Aleixo, Alexandre

    2004-06-01

    Among those few hypotheses of Amazonian diversification amenable to falsification by phylogenetic and population genetics methods, three can be singled out because of their general application to vertebrates: the riverine barrier, the refuge, and the Miocene marine incursion hypotheses. I used phylogenetic and population genetics methods to reconstruct the diversification history of the upland (terra-firme) forest superspecies Xiphorhynchus spixii/elegans (Aves: Dendrocolaptidae) in Amazonia, and to evaluate predictions of the riverine barrier, refuge, and Miocene marine incursion hypotheses. Phylogeographic and population genetics analyses of the X. spixiilelegans superspecies indicated that the main prediction of the riverine barrier hypothesis (that sister lineages occur across major rivers) hold only for populations separated by "clear-water" rivers located on the Brazilian shield, in central and eastern Amazonia; in contrast, "white-water" rivers located in western Amazonia did not represent areas of primary divergence for populations of this superspecies. The main prediction derived from the refuge hypothesis (that populations of the X. spixii/elegans superspecies would show signs of past population bottlenecks and recent demographic expansions) was supported only for populations found in western Amazonia, where paleoecological data have failed to support past rainforest fragmentation and expansion of open vegetation types; conversely, populations from the eastern and central parts of Amazonia, where paleoecological data are consistent with an historical interplay between rainforest and open vegetation types, did not show population genetics attributes expected under the refuge hypothesis. Phylogeographic and population genetics data were consistent with the prediction made by the Miocene marine incursion hypothesis that populations of the X. spixii/elegans superspecies found on the Brazilian shield were older than populations from other parts of Amazonia. In contrast, the phylogeny obtained for lineages of this superspecies falsified the predicted monophyly of Brazilian shield populations, as postulated by the Miocene marine incursion hypothesis. In general, important predictions of both riverine barrier and Miocene marine incursion hypotheses were supported, indicating that they are not mutually exclusive; in fact, the data presented herein suggest that an interaction among geology, sea level changes, and hydrography created opportunities for cladogenesis in the X. spixii/elegans superspecies at different temporal and geographical scales. PMID:15266979

  19. April 6, 2009 Contact: FOR IMMEDIATE RELEASE Jason Mockford

    E-print Network

    Sze, Lawrence

    . Opening Ceremonies will begin at 10:00 a.m. on Dexter Lawn. Activities following opening ceremonies will include a Kids Fair, live music, RoboRodentia, the Cal Poly Tractor Pull, Cal Poly Rodeo, Open House's activities include an opportunity to meet college deans, tour the campus and departments and become

  20. Conservation Ecology & Entomology Department Dr Sonja Matthee

    E-print Network

    Geldenhuys, Jaco

    (Rodentia: Muridae). Parasitology DOI: http://dx.doi.org/10.1017/S003118201200217X 2. Van Der Mescht, L., le for a rodent host and its fleas. Parasitology, 140: 368-377 3. Drexler, J.F., Corman, V.M., Müller, M. A new species of Ixodes (Acari: Ixodidae) from South African Mammals. Journal of Parasitology, 97: 389

  1. Extinction of the autochthonous small mammals of Mallorca (Gymnesic Islands,

    E-print Network

    Binford, Michael W.

    ORIGINAL ARTICLE Extinction of the autochthonous small mammals of Mallorca (Gymnesic Islands-mail: vieapba@uib.es Abstract Aim To investigate the chronology, causes and consequences of the extinction of two extinct endemic small mammals from Mallorca: the Balearic dormouse, Eliomys morpheus (Rodentia

  2. RONGEURS DU MIOCENE SUPERIEUR DE CHORORA, ETHIOPIE: MURINAE, DENDROMURINAE ET CONCLUSIONS

    E-print Network

    Paris-Sud XI, Université de

    RONGEURS DU MIOCENE SUPERIEUR DE CHORORA, ETHIOPIE: MURINAE, DENDROMURINAE ET CONCLUSIONS par Denis, Muridae Key-words: Late Miocene, Ethiopia, Rodentia, Muridae UPR 2147 CNRS - 44 rue de l'Amiral Mouchez of the Late Miocene. INTRODUCTION Le site de Chorora, dans la localité-type de la formation du même nom, a d

  3. Individual recognition and incest avoidance in eusocial common mole-rats rather than reproductive suppression by parents

    Microsoft Academic Search

    H. Burda

    1995-01-01

    Non-reproductive females in families of eusocial common mole-rats (Cryptomys sp., Rodentia) are not suppressed by their mother, (either behaviourally or pheromonally) as is generally assumed. They do not mate with their father and brothers simply because they are not sexually attractive for them (and vice versa). The incest avoidance is based on the capability to recognize (and keep in memory

  4. Animal's Behavior in the \\

    Microsoft Academic Search

    Bahija E. Al-Behbehani; Hussain M. Ibrahim

    2007-01-01

    It was not the objective of the present study to provide a detailed list of species of wildlife occurring in the study area, but only to deal with some of the more conspicuous representatives and record chance sightings. In the present study, the behavior of four types of animals: Reptilia (snakes and vipers), Arachnida (scorpions), Insectivora (hedgehogs) and Rodentia (jerboa),

  5. The role of dogs as reservoirs of Leishmania parasites, with emphasis on Leishmania ( Leishmania) infantum and Leishmania ( Viannia) braziliensis

    Microsoft Academic Search

    Filipe Dantas-Torres

    2007-01-01

    Leishmania parasites cause a group of diseases collectively known as leishmaniases. The primary hosts of Leishmania are sylvatic mammals of several orders (Rodentia, Marsupialia, Carnivora, etc.). Under certain circumstances, particularly in peridomestic and domestic transmission foci, synanthropic and domestic animals can act as source of infection for phlebotomine sand fly vectors. Dogs have long been implicated as the main domestic

  6. Studies on Neotropical Fauna and Environment Vol. 47, No. 3, December 2012, 157170

    E-print Network

    Anderson, Robert P.

    @sci.ccny.cuny.edu the surrounding lowlands originally corresponded to drier vegetation types (deciduous forests, thorn forests: biogeography; cloud forest; Didelphimorphia; endemism; Rodentia; Venezuela Introduction Islands provide key insights into ecology and evolu- tion (Lomolino & Heaney 2004). Furthermore, many similarities exist

  7. Cryptosporidium: a water-borne zoonotic parasite

    Microsoft Academic Search

    Ronald Fayer

    2004-01-01

    Of 155 species of mammals reported to be infected with Cryptosporidium parvum or C. parvum-like organisms most animals are found in the Orders Artiodactyla, Primates, and Rodentia. Because Cryptosporidium from most of these animals have been identified by oocyst morphology alone with little or no host specificity and\\/or molecular data to support identification it is not known how many of

  8. Evidence for rodent-common and species-typical limb and digit use in eating, derived from a comparative analysis of ten rodent species

    Microsoft Academic Search

    I. Q. Whishaw; J. R. Sarna; S. M. Pellis

    1998-01-01

    Order Rodentia comprises a vast portion of mammalian species (1814 species), which occupy extremely diverse habitats requiring very distinct motor specializations (e.g. burrowing, hopping, climbing, flying and swimming). Although early classification of paw use ability suggests rodents are impoverished relative to primates and make little use of their paws, there have been no systematic investigations of paw use in rodents.

  9. Mol. Biol. Evol. 18(9):17081719. 2001 2001 by the Society for Molecular Biology and Evolution. ISSN: 0737-4038

    E-print Network

    clade of rodents. To explore phylogenetic relationships among 23 species and 5 undescribed forms, we Diversification in South American Tuco-tucos (Genus Ctenomys, Rodentia: Octodontidae): A Phylogenetic Approach; and Laboratorio de Evolucio´n, Facultad de Ciencias, Montevideo, Uruguay We investigated the relationship between

  10. Evolution, 3 2 ( 2 ) , 1978, pp. 334-341 CHROMOSOMAL HOMOLOGY AND DIVERGENCE BETWEEN SIBLING

    E-print Network

    Baker, Robert J.

    , specia- tion in the Peromyscus maniculatus com- plex has been accompanied by consider- able change SPECIES OF DEER MICE: PEROMYSCUS MANICULA TUS AND P. MELANOTIS (RODENTIA, CRICETIDAE) IRAF. GREENBAUD. melanotis and P. maniculatus, as determined by G- and C- band comparisons. This study was under- taken

  11. Spot-on Treatments of Diflubenzuron and Permethrin to Control a Guinea Pig Louse, Gliricola Porcelli (Phthiraptera: Gyropidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Guinea pigs (Cavia porcellus (L.)) (Rodentia: Caviidae) are pets and laboratory animals. They can be infested by a chewing louse, Gliricola porcelli (Schrank) (Phthiraptera: Gyropidae), which is fairly common in some animal rearing facilities, pet stores, and on wild guinea pigs. Infestation with G....

  12. INVASIVE RODENTS ON ISLANDS Direct and indirect effects of rats: does rat eradication

    E-print Network

    Fukami, Tadashi

    . rattus, R. norvegicus and R. exulans) have been eradicated from islands has greatly accelerated Springer Science+Business Media B.V. 2008 Abstract Introduced rats (Rattus spp.) can affect island Á Woody seedlings Introduction Humans have introduced rats (Rattus spp.; Rodentia: Muridae

  13. Sound Localization in a Predatory Rodent, the Northern Grasshopper Mouse (Onychomys leucogaster )

    Microsoft Academic Search

    Rickye S. Heffner; Henry E. Heffner

    1988-01-01

    A comparison of the ability of mammals to localize sound revealed that among the animals examined to date, none of the rodents have been able to localize as accurately as the carnivores. Because all of these rodents are prey animals, the question arises as to whether their poor localization acuity is a phyletic trait of Rodentia or whether it is

  14. Molecular systematics of hystricognath rodents: evidence from the mitochondrial 12S rRNA gene.

    PubMed

    Nedbal, M A; Allard, M W; Honeycutt, R L

    1994-09-01

    Nucleotide sequence variation among 22 representatives of 14 families of hystricognathid rodents was examined using an 814-bp region of the mitochondrial 12S ribosomal RNA (rRNA) gene composing domains I-III. The purpose of this study was twofold. First, the phylogenetic relationships among Old World phiomorph (primarily African) and New World caviomorph (primarily South American) families were investigated, with a special emphasis on testing hypotheses pertaining to the origin of New World families and the identification of major monophyletic groups. Second, divergence times derived from molecular data were compared to those suggested by the fossil record. The resultant 12S rRNA gene phylogeny, analyzed separately and in combination with other morphological and molecular data, supported a monophyletic Caviomorpha. This finding is counter to the idea of a multiple origin for the South American families. The most strongly supported relationships within the Caviomorpha were a monophyletic Octodontoidea (containing five families) and the placement of New World porcupines (family Erethizontidae) as the most divergent family. Although comparisons to other data were more equivocal, the most parsimonious 12S rRNA trees also supported a monophyletic Phiomorpha that could be subdivided into two major groups, a clade containing the Thryonomyoidea (Thryonomyidae and Petromuridae) plus Bathyergidae and the more divergent Hystricidae (Old World porcupines). No significant differences in rates of 12S rRNA gene divergence were observed for hystricognathids in comparison to other rodent groups. Although time since divergence estimates were influenced by the fossil dates chosen to calibrate absolute rates, the overall divergence times derived from both transversions only and Kimura corrected distances and calibrations using two independent dates revealed a divergence time between Old and New World groups dating in the Eocene. PMID:7820285

  15. Comparative analysis of microsatellite variability in five macaw species (Psittaciformes, Psittacidae): Application for conservation

    PubMed Central

    Presti, Flavia T.; Oliveira-Marques, Adriana R.; Caparroz, Renato; Biondo, Cibele; Miyaki, Cristina Y.

    2011-01-01

    Cross-amplification was tested and variability in microsatellite primers (designed for Neotropical parrots) compared, in five macaw species, viz., three endangered blue macaws (Cyanopsitta spixii [extinct in the wild], Anodorhynchus leari [endangered] and Anodorhynchus hyacinthinus [vulnerable]), and two unthreatened red macaws (Ara chloropterus and Ara macao). Among the primers tested, 84.6% successfully amplified products in C. spixii, 83.3% in A. leari, 76.4% in A. hyacinthinus, 78.6% in A. chloropterus and 71.4% in A. macao. The mean expected heterozygosity estimated for each species, and based on loci analyzed in all the five, ranged from 0.33 (A. hyacinthinus) to 0.85 (A. macao). As expected, the results revealed lower levels of genetic variability in threatened macaw species than in unthreatened. The low combined probability of genetic identity and the moderate to high potential for paternity exclusion, indicate the utility of the microsatellite loci set selected for each macaw species in kinship and population studies, thus constituting an aid in planning in-situ and ex-situ conservation. PMID:21734841

  16. Comparative analysis of microsatellite variability in five macaw species (Psittaciformes, Psittacidae): Application for conservation.

    PubMed

    Presti, Flavia T; Oliveira-Marques, Adriana R; Caparroz, Renato; Biondo, Cibele; Miyaki, Cristina Y

    2011-04-01

    Cross-amplification was tested and variability in microsatellite primers (designed for Neotropical parrots) compared, in five macaw species, viz., three endangered blue macaws (Cyanopsitta spixii [extinct in the wild], Anodorhynchus leari [endangered] and Anodorhynchus hyacinthinus [vulnerable]), and two unthreatened red macaws (Ara chloropterus and Ara macao). Among the primers tested, 84.6% successfully amplified products in C. spixii, 83.3% in A. leari, 76.4% in A. hyacinthinus, 78.6% in A. chloropterus and 71.4% in A. macao. The mean expected heterozygosity estimated for each species, and based on loci analyzed in all the five, ranged from 0.33 (A. hyacinthinus) to 0.85 (A. macao). As expected, the results revealed lower levels of genetic variability in threatened macaw species than in unthreatened. The low combined probability of genetic identity and the moderate to high potential for paternity exclusion, indicate the utility of the microsatellite loci set selected for each macaw species in kinship and population studies, thus constituting an aid in planning in-situ and ex-situ conservation. PMID:21734841

  17. The density-dependent formation of extended maternal families of the montane vole, Microtus montanus nanus

    Microsoft Academic Search

    Frederick J. Jannett

    1978-01-01

    1.Montane voles (Microtus montanus; Rodentia: Muridae) were studied in unconfined populations and in an enclosure in open fields in Wyoming. The field work involved capture-mark-recapture grids, tagging of select individuals with irradiated wires, and behavioral observations.2.When not nesting in proximity to another parous female in the field, the M. montanus dam abandoned her brood nest and young at about 15

  18. Special Publication No. 6, Subject: Nematoda and Nematode Diseases, Part 3: Supergenera, Genera, Species, and Subspecies: F-M. 

    E-print Network

    Doss, Mildred A.

    1985-01-01

    . Rodentia Agouti ???? Amblyomma spp. (Fairchild, G. ?. , Kohls, G. ?. , & Tipton, V. J., (1966A), 167-219) (Panama) Amblyomma coelebs (Fairchild, G. ?. , Kohls, G. ?. , Tipton, V. J., (1966A), 167-219) (Panama) Amblyomma pacae (Fairchild, G.... ?. , Kohls, G. ?. , ? Tipton, V. J., (1966A), 167-219) (Panama & British Honduras) Amblyomma pacae (Os orno-Me s a, ?. , (1940A), 6-24) (lado interno de la cadera; Colombia) Ixodes sp. (Fairchild, G. ?., Kohls, G. ?. , & Tipton, V. J., (1966A), 167...

  19. Energetics of hibernating yellow-bellied marmots ( Marmota flaviventris)

    Microsoft Academic Search

    Kenneth B. Armitage; Daniel T. Blumstein; Brett C. Woods

    2003-01-01

    Yellow-bellied marmots (Rodentia: Sciuridae) typically hibernate for eight months. This study explored energetic costs of hibernation in young and adults at 10 and 6 °C. Age significantly affected the percent time torpid, total and mass-specific Vo2, use of energy during torpor, and daily mass loss at 6 °C. Thus young had a higher mass-specific Vo2 during a torpor bout, which

  20. Peroxisomal changes during hiberation of jerboa (Jaculus orientalis)

    Microsoft Academic Search

    M. Kabine; M Cherkaoui-Malki; C.-C. Clémencet; M. S. El Kebbaj; N. Latruffe

    1998-01-01

    As a member of the order of Rodentia, jerboa (Jaculus orientalis) is a natural deep hibernator and lives in subdesert highland\\u000a in many parts of the world, including Morocco. Its small size (adult body weight ?100 g), availability in the wild, tolerance\\u000a to laboratory conditions, and some unique peroxisomal properties make it a suitable research subject for exploring peroxisome\\u000a biogenesis

  1. Mites of the genus Schizocarpus Trouessart, 1896 (Acariformes: Chirodiscidae) from the North American beavers (Castor canadensis) in Russia.

    PubMed

    Bochkov, A V; Saveljev, A P

    2014-01-01

    Four native species of parasitic mites belonging to the genus Schizocarpus Trouessart, 1896 (Acariformes: Chirodiscidae) are recorded on the North American beaver Castor canadensis Kuhl, 1820 (Rodentia: Castoridae) from Russia. Totally ten beavers from all three main geographically isolated populations of in Russia (Leningrad Province, Voronezh Biosphere Reserve (beaver farm) and Khabarovsk Territory) were examined. Additionally, in captivity (Voronezh beaver farm) eight species were recorded switched from the Eurasian beaver Castor fiber Linnaeus, 1758 on C. canadensis. PMID:25936168

  2. Viability of X-autosome translocations in mammals: an epigenomic hypothesis from a rodent case-study

    Microsoft Academic Search

    G. Dobigny; C. Ozouf-Costaz; C. Bonillo; V. Volobouev

    2004-01-01

    X-autosome translocations are highly deleterious chromosomal rearrangements due to meiotic disruption, the effects of X-inactivation on the autosome, and the necessity of maintaining different replication timing patterns between the two segments. In spite of this, X-autosome translocations are not uncommon. We here focus on the genus Taterillus (Rodentia, Gerbillinae) which provides two sister lineages differing by two autosome–gonosome translocations. Despite

  3. Domestic, peridomestic and wild hosts in the transmission of Trypanosoma cruzi in the Caatinga area colonised by Triatoma brasiliensis

    PubMed Central

    Bezerra, Claudia Mendonça; Cavalcanti, Luciano Pamplona de Góes; de Souza, Rita de Cássia Moreira; Barbosa, Silvia Ermelinda; Xavier, Samanta Cristina das Chagas; Jansen, Ana Maria; Ramalho, Relrison Dias; Diotaiut, Liléia

    2014-01-01

    The role played by different mammal species in the maintenance of Trypanosoma cruzi is not constant and varies in time and place. This study aimed to characterise the importance of domestic, wild and peridomestic hosts in the transmission of T. cruzi in Tauá, state of Ceará, Caatinga area, Brazil, with an emphasis on those environments colonised by Triatoma brasiliensis. Direct parasitological examinations were performed on insects and mammals, serologic tests were performed on household and outdoor mammals and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53), while in pigs it was 6% (2/34). The percentages of the most abundantly infected wild animals were as follows: Thrichomys laurentius 74% (83/112) and Kerodon rupestris 10% (11/112). Of the 749 triatomines collected in the household research, 49.3% (369/749) were positive for T. brasiliensis, while 6.8% were infected with T. cruzi (25/369). In captured animals, T. brasiliensis shares a natural environment with T. laurentius, K. rupestris, Didelphis albiventris, Monodelphis domestica, Galea spixii, Wiedomys pyrrhorhinos, Conepatus semistriatus and Mus musculus. In animals identified via their food source, T. brasiliensis shares a natural environment with G. spixii, K. rupestris, Capra hircus, Gallus gallus, Tropidurus oreadicus and Tupinambis merianae. The high prevalence of T. cruzi in household and peridomiciliar animals reinforces the narrow relationship between the enzootic cycle and humans in environments with T. brasiliensis and characterises it as ubiquitous. PMID:25410992

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

    PubMed

    Horn, Charles C; Kimball, Bruce A; Wang, Hong; Kaus, James; Dienel, Samuel; Nagy, Allysa; Gathright, Gordon R; Yates, Bill J; Andrews, Paul L R

    2013-01-01

    The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity-key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed. PMID:23593236

  5. Why Can’t Rodents Vomit? A Comparative Behavioral, Anatomical, and Physiological Study

    PubMed Central

    Horn, Charles C.; Kimball, Bruce A.; Wang, Hong; Kaus, James; Dienel, Samuel; Nagy, Allysa; Gathright, Gordon R.; Yates, Bill J.; Andrews, Paul L. R.

    2013-01-01

    The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity–key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed. PMID:23593236

  6. Variance of molecular datings, evolution of rodents and the phylogenetic affinities between Ctenodactylidae and Hystricognathi.

    PubMed

    Huchon, D; Catzeflis, F M; Douzery, E J

    2000-02-22

    The von Willebrand factor (vWF) gene has been used to understand the origin and timing of Rodentia evolution in the context of placental phylogeny vWF exon 28 sequences of 15 rodent families and eight non-rodent eutherian clades are analysed with two different molecular dating methods (uniform clock on a linearized tree; quartet dating). Three main conclusions are drawn from the study of this nuclear exon. First, Ctenodactylidae (gundis) and Hystricognathi (e.g. porcupines, guinea-pigs, chinchillas) robustly cluster together in a newly recognized clade, named 'Ctenohystrica'. The Sciurognathi monophyly is subsequently rejected. Pedetidae (springhares) is an independent and early diverging rodent lineage, suggesting a convergent evolution of the multiserial enamel of rodent incisors. Second, molecular date estimates are here more influenced by accuracy and choice of the palaeontological temporal references used to calibrate the molecular clock than by either characters analysed (nucleotides versus amino acids) or species sampling. The caviomorph radiation at 31 million years (Myr) and the pig porpoise split at 63 Myr appear to be reciprocally compatible dates. Third, during the radiation of Rodentia, at least three lineages (Gliridae, Sciuroidea and Ctenohystrica) emerged close to the Cretaceous-Tertiary boundary, and their common ancestor separated from other placental orders in the Late Cretaceous. PMID:10722222

  7. Variance of molecular datings, evolution of rodents and the phylogenetic affinities between Ctenodactylidae and Hystricognathi.

    PubMed Central

    Huchon, D; Catzeflis, F M; Douzery, E J

    2000-01-01

    The von Willebrand factor (vWF) gene has been used to understand the origin and timing of Rodentia evolution in the context of placental phylogeny vWF exon 28 sequences of 15 rodent families and eight non-rodent eutherian clades are analysed with two different molecular dating methods (uniform clock on a linearized tree; quartet dating). Three main conclusions are drawn from the study of this nuclear exon. First, Ctenodactylidae (gundis) and Hystricognathi (e.g. porcupines, guinea-pigs, chinchillas) robustly cluster together in a newly recognized clade, named 'Ctenohystrica'. The Sciurognathi monophyly is subsequently rejected. Pedetidae (springhares) is an independent and early diverging rodent lineage, suggesting a convergent evolution of the multiserial enamel of rodent incisors. Second, molecular date estimates are here more influenced by accuracy and choice of the palaeontological temporal references used to calibrate the molecular clock than by either characters analysed (nucleotides versus amino acids) or species sampling. The caviomorph radiation at 31 million years (Myr) and the pig porpoise split at 63 Myr appear to be reciprocally compatible dates. Third, during the radiation of Rodentia, at least three lineages (Gliridae, Sciuroidea and Ctenohystrica) emerged close to the Cretaceous-Tertiary boundary, and their common ancestor separated from other placental orders in the Late Cretaceous. PMID:10722222

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

    PubMed

    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. PMID:25622576

  9. Low resolution scanning electron microscopy of cerebellar neurons and neuroglial cells of the granular layer.

    PubMed

    Castejón, O J

    1984-01-01

    Teleost fishes, Arius Spixii and Salmo trout and adult Swiss albino mice have been processed with the freeze-fracture technique for SEM to explore the inner cytoplasmic and nuclear surface details of neurons and neuroglial cells. The specimens were fixed by vascular perfusion with Karnovsky fixative and 2-3 mm thick cerebellar slices were subsequently fixed by immersion in the same fixative. They were postfixed in osmium tetroxide, dehydrated in ethanol, frozen in Freon 22, cooled by liquid nitrogen and fractured. After thawing in ethanol, they were critically point dried, coated with gold-palladium and viewed by SEM. The surface features of perikaryon were examined at low resolution and magnifications. The image of endoplasmic reticulum, GERL complex and chromatin were described in fractured cerebellar neurons (granule and Golgi cells). The fractured protoplasmic astrocytes displayed a characteristic glass surface appearance of cytoplasmic body and processes, which facilitated their recognition at the neuropile and perivascular region. The oligodendrocytes appeared as fusiform cells depicting a thin rim of perinuclear cytoplasm. The surface view of endoplasmic reticulum was well studied at the nuclear poles. Fine cytoplasmic beaded canaliculi appeared connecting the outer surface of nuclear envelope with the plasma membrane inner surface. The nucleus exhibited well developed peripheral heterochromatin masses forming anastomotic bands separated by vacuolar spaces. The SEM nerve and neuroglial cell fractographs were compared with similar images obtained by conventional transmission electron microscopy and freeze etching technique. PMID:6505621

  10. Rodents for comparative aging studies: from mice to beavers

    PubMed Central

    Bozzella, Michael J.; Seluanov, Andrei

    2008-01-01

    After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents. PMID:19424861

  11. The organizational variability of the rodent somatosensory cortex.

    PubMed

    Santiago, L F; Rocha, E G; Freire, M A M; Dias, I A; Lent, R; Houzel, J C; Picanço-Diniz, C W; Pereira, A; Franca, J G

    2007-01-01

    Rodentia is the largest mammalian order, with more than 2,000 species displaying a great diversity of morphological characteristics and living in different ecological niches (terrestrial, semi-aquatic, arboreal and fossorial). Analysis of the organization of the somatosensory areas in six species of rodents allowed us to demonstrate that although these species share a similar neocortical blueprint with other eutherian mammals, important differences exist between homologous areas across different species, probably as a function of both lifestyle and peripheral sensory specializations typical of each species. We based this generalization on a phylogenetic comparison of the intrinsic organization of the primary somatosensory area (SI) across representatives of different rodent suborders. This analysis revealed considerable structural variability, including the differential expansion of cortical representation of specific body parts (cortical amplification) as well as the parcellation of areas into processing modules. PMID:18019610

  12. A web-database of mammalian morphology and a reanalysis of placental phylogeny

    E-print Network

    Asher, Robert J

    2007-07-03

    GTR+I+G atp7a GTR+I+G rag2 HKY+I+G bdnf GTR+G tyr SYR+I+G brca1 GTR+I+G vwf GTR+I+G cnr1 GTR+I+G zfx HKY+I+G crem GTR+I+G mtRNA GTR+I+G Table 1: Templeton and Winning Sites tests of alternative topologies, varying placement of the placental root, based... on the location of the root. This falls either at Atlantogenata (Afrotheria+Xenarthra) [13,14], Xenarthra [12], or Glires (Rodentia+Lagomorpha) [15]. Earlier analyses of mito- chondrial protein-coding genes [16] and of a combined although in [16] erinaceids were...

  13. Rodents for comparative aging studies: from mice to beavers.

    PubMed

    Gorbunova, Vera; Bozzella, Michael J; Seluanov, Andrei

    2008-09-01

    After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents. PMID:19424861

  14. The use of semen evaluation and assisted reproduction in Spix's macaws in terms of species conservation.

    PubMed

    Fischer, Dominik; Neumann, Daniel; Purchase, Cromwell; Bouts, Tim; Meinecke-Tillmann, Sabine; Wehrend, Axel; Lierz, Michael

    2014-01-01

    The Spix's macaw (Cyanopsitta spixii) is the rarest parrot on earth. The remaining captive population consists of 79 individuals. Captive propagation is ongoing to increase the number of individuals for future reintroduction back into the wild. Unfortunately, from 2004 to 2012, only 33 chicks hatched from 331 eggs. Semen evaluation and assisted reproduction might help to overcome this problem. Therefore, a recently developed electro-stimulated semen collection technique was used in Spix's macaws. Semen collection was successful in 39 of 78 attempts in 10 out of 17 males. Examination of the semen included evaluation of volume, color, consistency, contaminations and pH, as well as determination of motility, viability, morphology, concentration, and total count of spermatozoa. The median volume of semen samples was 5.6 µl. On average, 34.7 ± 21.9% (median 30%) of the sperm were motile and 23.1 ± 22.1% (median 16.5%) were progressively motile. In addition to spermatozoa, round cells were detected in the samples. Median sperm concentration was 15,500/µl (range 500-97,500/µl) and median viability was 50% (range 5-87%). Morphological examination revealed in 26.5% normal spermatozoa, high numbers of malformations of the head (50.2%) and tail region (20.5%), with 29% of all sperm showing multiple abnormalities. Artificial insemination was performed in three females; two eggs laid after artificial insemination had spermatozoa present on the perivitelline layer, suggesting the possible success of the insemination technique. Although no fertilization could be demonstrated, these preliminary results are promising, as they indicate that assisted reproduction might be a tool for species conservation in the Spix's macaw. PMID:24752991

  15. A Newly Emerged Cutaneous Leishmaniasis Focus in Northern Israel and Two New Reservoir Hosts of Leishmania major

    PubMed Central

    Faiman, Roy; Abbasi, Ibrahim; Jaffe, Charles; Motro, Yoav; Nasereddin, Abdelmagid; Schnur, Lionel F.; Torem, Moshe; Pratlong, Francine; Dedet, Jean-Pierre; Warburg, Alon

    2013-01-01

    In 2006/7, 18 cases of cutaneous leishmaniasis (CL) were reported for the first time from Sde Eliyahu (pop. 650), a village in the Beit She'an valley of Israel. Between 2007–2011, a further 88 CL cases were diagnosed bringing the total to 106 (16.3% of the population of Sde Eliyahu). The majority of cases resided in the south-western part of the village along the perimeter fence. The causative parasite was identified as Leishmania major Yakimoff & Schokhor, 1914 (Kinetoplastida: Trypanosomatidae). Phlebotomus papatasi (Scopoli), 1786 (Diptera: Psychodidae) was found to be the most abundant phlebotomine species comprising 97% of the sand flies trapped inside the village, and an average of 7.9% of the females were positive for Leishmania ITS1 DNA. Parasite isolates from CL cases and a sand fly were characterized using several methods and shown to be L. major. During a comprehensive survey of rodents 164 Levant voles Microtus guentheri Danford & Alston, 1880 (Rodentia: Cricetidae) were captured in alfalfa fields bordering the village. Of these 27 (16.5%) tested positive for Leishmania ITS1 DNA and shown to be L. major by reverse line blotting. A very high percentage (58.3% - 21/36) of Tristram's jirds Meriones tristrami Thomas, 1892 (Rodentia: Muridae), found further away from the village also tested positive for ITS1 by PCR. Isolates of L. major were successfully cultured from the ear of a wild jird found positive by ITS1 PCR. Although none of the wild PCR-positive voles exhibited external pathology, laboratory-reared voles that were infected by intradermal L. major inoculation, developed patent lesions and sand flies became infected by feeding on the ears of these laboratory-infected voles. This is the first report implicating M. guentheri and M. tristrami as reservoirs of Leishmania. The widespread co-distribution of M. guentheri and P. papatasi, suggests a significant threat from the spread of CL caused by L. major in the Middle East, central Asia and southern Europe. PMID:23437408

  16. Molecular and Paleontological Evidence for a Post-Cretaceous Origin of Rodents

    PubMed Central

    Wu, Shaoyuan; Wu, Wenyu; Zhang, Fuchun; Ye, Jie; Ni, Xijun; Sun, Jimin; Edwards, Scott V.; Meng, Jin; Organ, Chris L.

    2012-01-01

    The timing of the origin and diversification of rodents remains controversial, due to conflicting results from molecular clocks and paleontological data. The fossil record tends to support an early Cenozoic origin of crown-group rodents. In contrast, most molecular studies place the origin and initial diversification of crown-Rodentia deep in the Cretaceous, although some molecular analyses have recovered estimated divergence times that are more compatible with the fossil record. Here we attempt to resolve this conflict by carrying out a molecular clock investigation based on a nine-gene sequence dataset and a novel set of seven fossil constraints, including two new rodent records (the earliest known representatives of Cardiocraniinae and Dipodinae). Our results indicate that rodents originated around 61.7–62.4 Ma, shortly after the Cretaceous/Paleogene (K/Pg) boundary, and diversified at the intraordinal level around 57.7–58.9 Ma. These estimates are broadly consistent with the paleontological record, but challenge previous molecular studies that place the origin and early diversification of rodents in the Cretaceous. This study demonstrates that, with reliable fossil constraints, the incompatibility between paleontological and molecular estimates of rodent divergence times can be eliminated using currently available tools and genetic markers. Similar conflicts between molecular and paleontological evidence bedevil attempts to establish the origination times of other placental groups. The example of the present study suggests that more reliable fossil calibration points may represent the key to resolving these controversies. PMID:23071573

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

    PubMed

    Oliveriusová, Ludmila; N?mec, Pavel; Pavelková, Zuzana; Sedlá?ek, 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. PMID:24913128

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

    NASA Astrophysics Data System (ADS)

    Oliveriusová, Ludmila; N?mec, Pavel; Pavelková, Zuzana; Sedlá?ek, 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.

  19. Environment-related and host-related factors affecting the occurrence of lice on rodents in Central Europe.

    PubMed

    Stanko, Michal; Fri?ová, Jana; Miklisová, Dana; Khokhlova, Irina S; Krasnov, Boris R

    2015-06-01

    We studied the effects of environment- (habitat, season) and host-related (sex, body mass) factors on the occurrence of four species of lice (Insecta:Phthiraptera:Anoplura) on six rodent species (Rodentia:Muridae). We asked how these factors influence the occurrence of lice on an individual host and whether different rodent-louse associations demonstrate consistent trends in these effects. We found significant effects of at least one environment-related and at least one host-related factor on the louse occurrence in five of six host-louse associations. The effect of habitat was significant in two associations with the occurrence of lice being more frequent in lowland than in mountain habitats. The effect of season was significant in five associations with a higher occurrence of infestation during the warm season in four associations and the cold season in one association. Host sex affected significantly the infestation by lice in three associations with a higher frequency of infestation in males. Host body mass affected the occurrence of lice in all five associations, being negative in wood mice and positive in voles. In conclusion, lice were influenced not only by the host- but also by environment-related factors. The effects of the latter could be mediated via life history parameters of a host. PMID:25651932

  20. Hystricognathy vs Sciurognathy in the Rodent Jaw: A New Morphometric Assessment of Hystricognathy Applied to the Living Fossil Laonastes (Diatomyidae)

    PubMed Central

    Hautier, Lionel; Lebrun, Renaud; Saksiri, Soonchan; Michaux, Jacques; Vianey-Liaud, Monique; Marivaux, Laurent

    2011-01-01

    While exceptional for an intense diversification of lineages, the evolutionary history of the order Rodentia comprises only a limited number of morphological morphotypes for the mandible. This situation could partly explain the intense debates about the taxonomic position of the latest described member of this clade, the Laotian rock rat Laonastes aenigmamus (Diatomyidae). This discovery has re-launched the debate on the definition of the Hystricognathi suborder identified using the angle of the jaw relative to the plane of the incisors. Our study aims to end this ambiguity. For clarity, it became necessary to revisit the entire morphological diversity of the mandible in extant and extinct rodents. However, current and past rodent diversity brings out the limitations of the qualitative descriptive approach and highlights the need for a quantitative approach. Here, we present the first descriptive comparison of the masticatory apparatus within the Ctenohystrica clade, in combining classic comparative anatomy with morphometrical methods. First, we quantified the shape of the mandible in rodents using 3D landmarks. Then, the analysis of osteological features was compared to myological features in order to understand the biomechanical origin of this morphological diversity. Among the morphological variation observed, the mandible of Laonastes aenigmamus displays an intermediate association of features that could be considered neither as sciurognathous nor as hystricognathous. PMID:21490933

  1. Energetics of hibernating yellow-bellied marmots (Marmota flaviventris).

    PubMed

    Armitage, Kenneth B; Blumstein, Daniel T; Woods, Brett C

    2003-01-01

    Yellow-bellied marmots (Rodentia: Sciuridae) typically hibernate for eight months. This study explored energetic costs of hibernation in young and adults at 10 and 6 degrees C. Age significantly affected the percent time torpid, total and mass-specific VO(2), use of energy during torpor, and daily mass loss at 6 degrees C. Thus young had a higher mass-specific VO(2) during a torpor bout, which was attributed to higher metabolism during deep torpor. Total VO(2) during a bout was higher in young and there were significant temperature/age interactions; young had a higher VO(2) during torpor and deep torpor at 6 degrees C than at 10 degrees C. VO(2) increased at T(E)s below 6 degrees C. Young had a higher daily mass loss than adults at 6 degrees C. Euthermy increased energetic costs 19.3 times over those of torpor and 23.5 times over those of deep torpor. Energy costs are minimized by spending 88.6% of the hibernation period in torpor, by the rapid decline of VO(2) from euthermy to torpor and by allowing T(B) to decline at low T(E). Torpidity results in average energy savings during winter of 83.3% of the costs of maintaining euthermy. Energy savings are greater than those reported for Marmota marmota and M. monax. PMID:12507613

  2. A comparative survey of the mast cells of the mammalian brain.

    PubMed Central

    Kiernan, J A

    1976-01-01

    A search for mast cells has been made in the brains of 18 mammalian species in 13 families in the orders Insectivora, Primates, Rodentia and Carnivora. In the larger animals, only the diencephalon and olfactory bulbs were examined. Mast cells were identified by virtue of their heparin-containing granules, which are stained by Alcian blue 8GX and, metachromatically, by toluidine blue 0. Within the cerebral parenchyma, mast cells were confined to the dorsal diencephalon of Erinaceus europaeus (hedgehog), Tupaia glis (tree-shrew) and Nycticebus coucang (slow loris). Some cells were next to capillaries; others were not. Mast cells were sometimes found, though rarely, in the intracerebral perivascular connective tissue leptomeninges and choroid plexuses of some of the other species examined. It is concluded that pericapillary cells (pericytes), which have been called mast cells by some investigators, are not in fact mast cells since there is no evidence for the presence of heparin. The functions of mast cells in the brain are unknown. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:819404

  3. More Novel Hantaviruses and Diversifying Reservoir Hosts — Time for Development of Reservoir-Derived Cell Culture Models?

    PubMed Central

    Eckerle, Isabella; Lenk, Matthias; Ulrich, Rainer G.

    2014-01-01

    Due to novel, improved and high-throughput detection methods, there is a plethora of newly identified viruses within the genus Hantavirus. Furthermore, reservoir host species are increasingly recognized besides representatives of the order Rodentia, now including members of the mammalian orders Soricomorpha/Eulipotyphla and Chiroptera. Despite the great interest created by emerging zoonotic viruses, there is still a gross lack of in vitro models, which reflect the exclusive host adaptation of most zoonotic viruses. The usually narrow host range and genetic diversity of hantaviruses make them an exciting candidate for studying virus-host interactions on a cellular level. To do so, well-characterized reservoir cell lines covering a wide range of bat, insectivore and rodent species are essential. Most currently available cell culture models display a heterologous virus-host relationship and are therefore only of limited value. Here, we review the recently established approaches to generate reservoir-derived cell culture models for the in vitro study of virus-host interactions. These successfully used model systems almost exclusively originate from bats and bat-borne viruses other than hantaviruses. Therefore we propose a parallel approach for research on rodent- and insectivore-borne hantaviruses, taking the generation of novel rodent and insectivore cell lines from wildlife species into account. These cell lines would be also valuable for studies on further rodent-borne viruses, such as orthopox- and arenaviruses. PMID:24576845

  4. Frequent expansions of the bitter taste receptor gene repertoire during evolution of mammals in the Euarchontoglires clade.

    PubMed

    Hayakawa, Takashi; Suzuki-Hashido, Nami; Matsui, Atsushi; Go, Yasuhiro

    2014-08-01

    Genome studies of mammals in the superorder Euarchontoglires (a clade that comprises the orders Primates, Dermoptera, Scandentia, Rodentia, and Lagomorpha) are important for understanding the biological features of humans, particularly studies of medical model animals such as macaques and mice. Furthermore, the dynamic ecoevolutionary signatures of Euarchontoglires genomes may be discovered because many species in this clade are characterized by their successful adaptive radiation to various ecological niches. In this study, we investigated the evolutionary trajectory of bitter taste receptor genes (TAS2Rs) in 28 Euarchontoglires species based on homology searches of 39 whole-genome assemblies. The Euarchontoglires species possessed variable numbers of intact TAS2Rs, which ranged from 16 to 40, and their last common ancestor had at least 26 intact TAS2Rs. The gene tree showed that there have been at least seven lineage-specific events involving massive gene duplications. Gene duplications were particularly evident in the ancestral branches of anthropoids (the anthropoid cluster), which may have promoted the adaptive evolution of anthropoid characteristics, such as a trade-off between olfaction and other senses and the development of herbivorous characteristics. Subsequent whole-gene deletions of anthropoid cluster TAS2Rs in hominoid species suggest ongoing ectopic homologous recombination in the anthropoid cluster. These findings provide insights into the roles of adaptive sensory evolution in various ecological niches and important clues related to the molecular mechanisms that underlie taste diversity in Euarchontoglires mammalian species, including humans. PMID:24758778

  5. Rickettsial infections of fleas collected from small mammals on four islands in Indonesia.

    PubMed

    Barbara, Kathryn A; Farzeli, Arik; Ibrahim, Ima N; Antonjaya, Ungke; Yunianto, Andre; Winoto, Imelda; Ester; Perwitasari, Dian; Widjaya, Susana; Richards, Allen L; Williams, Maya; Blair, Patrick J

    2010-11-01

    Ectoparasites were sampled from small mammals collected in West Java, West Sumatra, North Sulawesi, and East Kalimantan, Indonesia, in 2007-2008 and were screened for evidence of infection from bacteria in the Rickettsaceae family. During eight trap nights at eight sites, 208 fleas were collected from 96 of 507 small mammals trapped from four orders (379 Rodentia; 123 Soricomorpha; two Carnivora; three Scandentia). Two species of fleas were collected: Xenopsylla cheopis (n = 204) and Nosopsyllus spp. (n = 4). Among the 208 fleas collected, 171 X. cheopis were removed from rats (Rattus spp.) and 33 X. cheopis from shrews (Suncus murinus). X. cheopis were pooled and tested for DNA from rickettsial agents Rickettsia typhi, Rickettsia felis, and spotted fever group rickettsiae. R. typhi, the agent of murine typhus, was detected in X. cheopis collected from small mammals in West Java and East Kalimantan. R. felis was detected in X. cheopis collected from small mammals in Manado, North Sulawesi. R. felis and spotted fever group rickettsiae were detected in a pool of X. cheopis collected from an animal in East Kalimantan. Sixteen percent of the X. cheopis pools were found positive for Rickettsia spp.; four (10.8%) R. typhi, one (2.7%) R. felis, and one (2.7%) codetection of R. felis and a spotted fever group rickettsia. These data suggest that rickettsial infections remain a threat to human health across Indonesia. PMID:21175069

  6. RNase 1 genes from the Family Sciuridae define a novel rodent ribonuclease cluster

    PubMed Central

    Siegel, Steven J.; Percopo, Caroline M.; Dyer, Kimberly D.; Zhao, Wei; Roth, V. Louise; Mercer, John M.; Rosenberg, Helene F.

    2009-01-01

    The RNase A ribonucleases are complex group of functionally diverse secretory proteins with conserved enzymatic activity. We have identified novel RNase 1 genes from four species of squirrel (order Rodentia, family Sciuridae). Squirrel RNase 1 genes encode typical RNase A ribonucleases, each with eight cysteines, a conserved CKXXNTF signature motif, and a canonical His12-Lys41-His119 catalytic triad. Two alleles encode Callosciurus prevostii RNase 1, which include a Ser18?Pro, analogous to the sequence polymorphisms found among the RNase 1 duplications in the genome of Rattus exulans. Interestingly, although the squirrel RNase 1 genes are closely related to one another (77 to 95% amino acid sequence identity), the cluster as a whole is distinct and divergent from the clusters including RNase 1 genes from other rodent species. We examined the specific sites at which Sciuridae RNase 1s diverge from Muridae / Cricetidae RNase 1s, and determined that the divergent sites are located on the external surface, with complete sparing of the catalytic crevice. The full significance of these findings awaits a more complete understanding of biological role of mammalian RNase 1s. PMID:19771477

  7. Evolution of genome organizations of squirrels (Sciuridae) revealed by cross-species chromosome painting.

    PubMed

    Li, Tangliang; O'Brien, Patricia C M; Biltueva, Larisa; Fu, Beiyuan; Wang, Jinhuan; Nie, Wenhui; Ferguson-Smith, Malcolm A; Graphodatsky, Alexander S; Yang, Fengtang

    2004-01-01

    With complete sets of chromosome-specific painting probes derived from flow-sorted chromosomes of human and grey squirrel (Sciurus carolinensis), the whole genome homologies between human and representatives of tree squirrels (Sciurus carolinensis, Callosciurus erythraeus), flying squirrels (Petaurista albiventer) and chipmunks (Tamias sibiricus) have been defined by cross-species chromosome painting. The results show that, unlike the highly rearranged karyotypes of mouse and rat, the karyotypes of squirrels are highly conserved. Two methods have been used to reconstruct the genome phylogeny of squirrels with the laboratory rabbit (Oryctolagus cuniculus) as the out-group: (1) phylogenetic analysis by parsimony using chromosomal characters identified by comparative cytogenetic approaches; (2) mapping the genome rearrangements onto recently published sequence-based molecular trees. Our chromosome painting results, in combination with molecular data, show that flying squirrels are phylogenetically close to New World tree squirrels. Chromosome painting and G-banding comparisons place chipmunks (Tamias sibiricus ), with a derived karyotype, outside the clade comprising tree and flying squirrels. The superorder Glires (orde Rodentia + order Lagomorpha) is firmly supported by two conserved syntenic associations between human chromosomes 1 and 10p homologues, and between 9 and 11 homologues. PMID:15241012

  8. The "five-sites" rule and the evolution of red and green color vision in mammals.

    PubMed

    Yokoyama, S; Radlwimmer, F B

    1998-05-01

    Amino acid changes S180A (S-->A at site 180), H197Y, Y277F, T285A, and A308S are known to shift the maximum wavelength of absorption (lambda max) of red and green visual pigments toward blue, essentially in an additive fashion. To test the generality of this "five-sites" rule, we have determined the partial amino acid sequences of red and green pigments from five mammalian orders (Artiodactyla, Carnivora, Lagomorpha, Perissodactyla, and Rodentia). The result suggests that cat (Felis catus), dog (Canis familiaris), and goat (Capra hircus) pigments all with AHYTA at the five critical sites have lambda max values of approximately 530 nm, whereas rat (Rattus norvegicus) pigment with AYYTS has a lambda max value of approximately 510 nm, which is accurately predicted by the five-sites rule. However, the observed lambda max values of the orthologous pigments of European rabbit (Oryctolagus cuniculus), white-tailed deer (Odocoileus virginianus), gray squirrel (Sciurus carolinensis), and guinea pig (Cavia procellus) are consistently more than 10 nm higher than the predicted values, suggesting the existence of additional molecular mechanisms for red and green color vision. The inferred amino acid sequences of ancestral organisms suggest that the extant mammalian red and green pigments appear to have evolved from a single ancestral green-red hybrid pigment by directed amino acid substitutions. PMID:9580985

  9. Surprisingly low risk of overheating during digging in two subterranean rodents.

    PubMed

    Okrouhlík, Jan; Burda, Hynek; Kunc, Petr; Knížková, Ivana; Šumbera, Radim

    2015-01-01

    Capacities for and constraints of heat dissipation are considered to be important factors governing maximum intensity and duration of physical activity. Subterranean mammals are endurance diggers, but because of lack of air currents in their burrows, high relative humidity and other physical constraints, the capacity of common mammalian cooling mechanisms underground is very limited. We analyzed surface and body core temperature changes after digging in soft and hard substrates in two species of African mole-rats (Bathyergidae, Rodentia); the social giant mole-rat Fukomys mechowii and the solitary silvery mole-rat Heliophobius argenteocinereus. As expected, we observed an increase of body core temperature in both species after digging in both substrates. Surprisingly, and contrary to our expectations, we observed remarkable decrease of mole-rats' surface temperature immediately after the end of the digging trials. This decrease was greater in soft and moister soil than that in hard and drier soil. Our results suggest that mole-rats may effectively avoid overheating in burrows by effective cooling while digging, especially in wet soil. This indicates that burrowing in soils moistened by rains could be easier than previously thought contributing thus to mole-rats success in challenging environment of subterranean burrows. PMID:25446207

  10. Physiologic reference ranges for captive black-tailed prairie dogs (Cynomys ludovicianus).

    PubMed

    Keckler, M Shannon; Gallardo-Romero, Nadia F; Langham, Gregory L; Damon, Inger K; Karem, Kevin L; Carroll, Darin S

    2010-05-01

    The black-tailed prairie dog (Cynomys ludovicianus) is a member of the order Rodentia and the family Sciuridae. Ecologically, prairie dogs are a keystone species in prairie ecology. This species is used as an animal model for human gallbladder disease and diseases caused by infection with Clostridium difficile, Yersinia pestis, Francisella tularensis, and most recently, Orthopoxvirus. Despite increasing numbers of prairie dogs used in research and kept as pets, few data are available on their baseline physiology in animal facility housing conditions. To establish baseline physiologic reference ranges, we designed a study using 18 wild-caught black-tailed prairie dogs. Telemetry data were analyzed to establish circadian rhythms for activity and temperature. In addition, hematologic and serum chemistry analyses were performed. Baseline measurements were used to establish the mean for each animal, which then were compiled and analyzed to determine the reference ranges. Here we present physiologic data on serum chemistry and hematology profiles, as well as weight, core body temperature, and daily activity patterns for black-tailed prairie dogs. These results reflect the use of multiple measurements from species- and age-matched prairie dogs and likely will be useful to ecologists, scientists interested in using this animal model in research, and veterinarians caring for pet prairie dogs. PMID:20587156

  11. Physiologic Reference Ranges for Captive Black-Tailed Prairie Dogs (Cynomys ludovicianus)

    PubMed Central

    Keckler, M Shannon; Gallardo-Romero, Nadia F; Langham, Gregory L; Damon, Inger K; Karem, Kevin L; Carroll, Darin S

    2010-01-01

    The black-tailed prairie dog (Cynomys ludovicianus) is a member of the order Rodentia and the family Sciuridae. Ecologically, prairie dogs are a keystone species in prairie ecology. This species is used as an animal model for human gallbladder disease and diseases caused by infection with Clostridium difficile, Yersinia pestis, Francisella tularensis, and most recently, Orthopoxvirus. Despite increasing numbers of prairie dogs used in research and kept as pets, few data are available on their baseline physiology in animal facility housing conditions. To establish baseline physiologic reference ranges, we designed a study using 18 wild-caught black-tailed prairie dogs. Telemetry data were analyzed to establish circadian rhythms for activity and temperature. In addition, hematologic and serum chemistry analyses were performed. Baseline measurements were used to establish the mean for each animal, which then were compiled and analyzed to determine the reference ranges. Here we present physiologic data on serum chemistry and hematology profiles, as well as weight, core body temperature, and daily activity patterns for black-tailed prairie dogs. These results reflect the use of multiple measurements from species- and age-matched prairie dogs and likely will be useful to ecologists, scientists interested in using this animal model in research, and veterinarians caring for pet prairie dogs. PMID:20587156

  12. Characterization of the North American beaver (Castor canadensis) papillomavirus genome.

    PubMed

    Rogovskyy, Artem S; Chen, Zigui; Burk, Robert D; Bankhead, Troy

    2014-01-10

    The papillomaviruses comprise a large group of viruses that cause proliferations of the stratified squamous epithelium of skin and mucosa in a variety of animals. An earlier report identified a novel papillomavirus of the North American beaver, Castor canadensis (CcanPV1) that was associated with cutaneous exophytic lesions. In the current study, we determined the sequence of the complete 7435 basepair genome of CcanPV1. The genome contains an Upstream Regulatory Region located between the end of L1 and the start of E6, and seven canonical papillomavirus open reading frames encoding five early (E6, E7, E1, E2, and E4) and two late (L2 and L1) proteins. No E5 open reading frame was detected. Phylogenetic analysis of the CcanPV1 genome places the virus between the genera Kappapapillomavirus and Mupapillomavirus. Analyses of the papillomavirus genomes detected in different species of the order Rodentia indicate these viruses do not form a monophyletic clade. PMID:24309404

  13. Seed predation and fruit damage of Solanum lycocarpum (Solanaceae) by rodents in the cerrado of central Brazil

    NASA Astrophysics Data System (ADS)

    Briani and, Denis C., Jr.; Guimarães, Paulo R.

    2007-01-01

    Although neotropical savannas and grasslands, collectively referred to as cerrado, are rich in seed-eating species of rodents, little is known about seed predation and its determinants in this habitat. In this study, we investigated seed predation and damage to fruits of the widespread shrub Solanum lycocarpum. In addition, the influence of two possible determinants (distance from the parental plant and total crop size) on the feeding behaviour of Oryzomys scotti (Rodentia, Sigmodontinae) was also examined. O. scotti were captured more frequently close to the shrubs or on shrub crops, indicating that these rodents were attracted to the shrubs and that seed predation was probably distance-dependent. Moreover, the proportion of damaged fruit on the plant decreased as the total crop size increased; consequently, more productive plants were attacked proportionally less by rodents. This pattern of fruit damage may reflect predator satiation caused by the consumption of a large amount of pulp. Alternatively, secondary metabolites in S. lycocarpum fruits may reduce the pulp consumption per feeding event, thereby limiting the number of fruits damaged.

  14. Microsatellite-encoded domain in rodent Sry functions as a genetic capacitor to enable the rapid evolution of biological novelty

    PubMed Central

    Chen, Yen-Shan; Racca, Joseph D.; Sequeira, Paul W.; Phillips, Nelson B.; Weiss, Michael A.

    2013-01-01

    The male program of therian mammals is determined by Sry, a transcription factor encoded by the Y chromosome. Specific DNA binding is mediated by a high mobility group (HMG) box. Expression of Sry in the gonadal ridge activates a Sox9-dependent gene regulatory network leading to testis formation. A subset of Sry alleles in superfamily Muroidea (order Rodentia) is remarkable for insertion of an unstable DNA microsatellite, most commonly encoding (as in mice) a CAG repeat–associated glutamine-rich domain. We provide evidence, based on an embryonic pre-Sertoli cell line, that this domain functions at a threshold length as a genetic capacitor to facilitate accumulation of variation elsewhere in the protein, including the HMG box. The glutamine-rich domain compensates for otherwise deleterious substitutions in the box and absence of nonbox phosphorylation sites to ensure occupancy of DNA target sites. Such compensation enables activation of a male transcriptional program despite perturbations to the box. Whereas human SRY requires nucleocytoplasmic shuttling and coupled phosphorylation, mouse Sry contains a defective nuclear export signal analogous to a variant human SRY associated with inherited sex reversal. We propose that the rodent glutamine-rich domain has (i) fostered accumulation of cryptic intragenic variation and (ii) enabled unmasking of such variation due to DNA replicative slippage. This model highlights genomic contingency as a source of protein novelty at the edge of developmental ambiguity and may underlie emergence of non–Sry-dependent sex determination in the radiation of Muroidea. PMID:23901118

  15. Sound localization in a predatory rodent, the northern grasshopper mouse (Onychomys leucogaster).

    PubMed

    Heffner, R S; Heffner, H E

    1988-03-01

    A comparison of the ability of mammals to localize sound revealed that among the animals examined to date, none of the rodents have been able to localize as accurately as the carnivores. Because all of these rodents are prey animals, the question arises as to whether their poor localization acuity is a phyletic trait of Rodentia or whether it is a trait common to prey species that may be under less selective pressure than predators to localize sound accurately. To answer this question, sound localization acuity was determined in a species that is both predatory and a rodent, the northern grasshopper mouse. Localization thresholds for a single 100-ms noise burst were determined for three grasshopper mice using a conditioned avoidance procedure. Their 50% discrimination threshold of 19 degrees is larger than that of any of the previously tested carnivores and well within the range of other rodents. However, calculations of the binaural sound localization cues available to rodents (based on their head size) suggest that the grasshopper mouse may make more efficient use of the available locus cues than other rodents. Thus, although the grasshopper mouse cannot localize as accurately as carnivores, it appears to be more accurate than predicted for a nonpredatory rodent of its size. PMID:3365945

  16. Evolutionary Insights from a Genetically Divergent Hantavirus Harbored by the European Common Mole (Talpa europaea)

    PubMed Central

    Kang, Hae Ji; Bennett, Shannon N.; Sumibcay, Laarni; Arai, Satoru; Hope, Andrew G.; Mocz, Gabor; Song, Jin-Won; Cook, Joseph A.; Yanagihara, Richard

    2009-01-01

    Background The discovery of genetically distinct hantaviruses in shrews (Order Soricomorpha, Family Soricidae) from widely separated geographic regions challenges the hypothesis that rodents (Order Rodentia, Family Muridae and Cricetidae) are the primordial reservoir hosts of hantaviruses and also predicts that other soricomorphs harbor hantaviruses. Recently, novel hantavirus genomes have been detected in moles of the Family Talpidae, including the Japanese shrew mole (Urotrichus talpoides) and American shrew mole (Neurotrichus gibbsii). We present new insights into the evolutionary history of hantaviruses gained from a highly divergent hantavirus, designated Nova virus (NVAV), identified in the European common mole (Talpa europaea) captured in Hungary. Methodology/Principal Findings Pair-wise alignment and comparison of the full-length S- and L-genomic segments indicated moderately low sequence similarity of 54–65% and 46–63% at the nucleotide and amino acid levels, respectively, between NVAV and representative rodent- and soricid-borne hantaviruses. Despite the high degree of sequence divergence, the predicted secondary structure of the NVAV nucleocapsid protein exhibited the characteristic coiled-coil domains at the amino-terminal end, and the L-segment motifs, typically found in hantaviruses, were well conserved. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, showed that NVAV formed a distinct clade that was evolutionarily distant from all other hantaviruses. Conclusions Newly identified hantaviruses harbored by shrews and moles support long-standing virus-host relationships and suggest that ancestral soricomorphs, rather than rodents, may have been the early or original mammalian hosts. PMID:19582155

  17. Faster Speciation and Reduced Extinction in the Tropics Contribute to the Mammalian Latitudinal Diversity Gradient

    PubMed Central

    Rolland, Jonathan; Condamine, Fabien L.; Jiguet, Frederic; Morlon, Hélène

    2014-01-01

    The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals) peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas) reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha), high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha), or both (Chiroptera and Rodentia). Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the “out of the tropics” hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern. PMID:24492316

  18. A First Generation Comparative Chromosome Map between Guinea Pig (Cavia porcellus) and Humans

    PubMed Central

    Romanenko, Svetlana A.; Perelman, Polina L.; Trifonov, Vladimir A.; Serdyukova, Natalia A.; Li, Tangliang; Fu, Beiyuan; O’Brien, Patricia C. M.; Ng, Bee L.; Nie, Wenhui; Liehr, Thomas; Stanyon, Roscoe; Graphodatsky, Alexander S.; Yang, Fengtang

    2015-01-01

    The domesticated guinea pig, Cavia porcellus (Hystricomorpha, Rodentia), is an important laboratory species and a model for a number of human diseases. Nevertheless, genomic tools for this species are lacking; even its karyotype is poorly characterized. The guinea pig belongs to Hystricomorpha, a widespread and important group of rodents; so far the chromosomes of guinea pigs have not been compared with that of other hystricomorph species or with any other mammals. We generated full sets of chromosome-specific painting probes for the guinea pig by flow sorting and microdissection, and for the first time, mapped the chromosomal homologies between guinea pig and human by reciprocal chromosome painting. Our data demonstrate that the guinea pig karyotype has undergone extensive rearrangements: 78 synteny-conserved human autosomal segments were delimited in the guinea pig genome. The high rate of genome evolution in the guinea pig may explain why the HSA7/16 and HSA16/19 associations presumed ancestral for eutherians and the three syntenic associations (HSA1/10, 3/19, and 9/11) considered ancestral for rodents were not found in C. porcellus. The comparative chromosome map presented here is a starting point for further development of physical and genetic maps of the guinea pig as well as an aid for genome assembly assignment to specific chromosomes. Furthermore, the comparative mapping will allow a transfer of gene map data from other species. The probes developed here provide a genomic toolkit, which will make the guinea pig a key species to unravel the evolutionary biology of the Hystricomorph rodents. PMID:26010445

  19. Evolution of C, D and S-Type Cystatins in Mammals: An Extensive Gene Duplication in Primates

    PubMed Central

    de Sousa-Pereira, Patrícia; Abrantes, Joana; Pinheiro, Ana; Colaço, Bruno; Vitorino, Rui; Esteves, Pedro J.

    2014-01-01

    Cystatins are a family of inhibitors of cysteine peptidases that comprises the salivary cystatins (D and S-type cystatins) and cystatin C. These cystatins are encoded by a multigene family (CST3, CST5, CST4, CST1 and CST2) organized in tandem in the human genome. Their presence and functional importance in human saliva has been reported, however the distribution of these proteins in other mammals is still unclear. Here, we performed a proteomic analysis of the saliva of several mammals and studied the evolution of this multigene family. The proteomic analysis detected S-type cystatins (S, SA, and SN) in human saliva and cystatin D in rat saliva. The evolutionary analysis showed that the cystatin C encoding gene is present in species of the most representative mammalian groups, i.e. Artiodactyla, Rodentia, Lagomorpha, Carnivora and Primates. On the other hand, D and S-type cystatins are mainly retrieved from Primates, and especially the evolution of S-type cystatins seems to be a dynamic process as seen in Pongo abelii genome where several copies of CST1-like gene (cystatin SN) were found. In Rodents, a group of cystatins previously identified as D and S has also evolved. Despite the high divergence of the amino acid sequence, their position in the phylogenetic tree and their genome organization suggests a common origin with those of the Primates. These results suggest that the D and S type cystatins have emerged before the mammalian radiation and were retained only in Primates and Rodents. Although the mechanisms driving the evolution of cystatins are unknown, it seems to be a dynamic process with several gene duplications evolving according to the birth-and-death model of evolution. The factors that led to the appearance of a group of saliva-specific cystatins in Primates and its rapid evolution remain undetermined, but may be associated with an adaptive advantage. PMID:25329717

  20. Historical biogeography of the strepsirhine primates of Madagascar.

    PubMed

    Tattersall, Ian

    2006-01-01

    Lying some 400 km off the coast of southeastern Africa, Madagascar is the world's largest oceanic island. It has been in roughly the same position relative to its parent continent for 120 million years, and as a consequence its mammal fauna is unusual in composition, with a low number of major taxa but a high diversity at lower taxonomic levels. Among Madagascar's native terrestrial mammals, only the orders Primates, Rodentia, Carnivora and Insectivora are represented (plus, until recently, the enigmatic and endemic Bibymalagasia, and Artiodactyla in the form of semiaquatic pygmy hippopotamuses). This reflects the fact that terrestrial mammals are notoriously poor over-water dispersers; yet at the same time the ancestors of all of Madagascar's mammals had to have crossed a wide oceanic barrier to get to the island at various points during the Tertiary. Here I examine the palaeogeographic evidence for potential land bridge or 'stepping-stone' connections with adjacent continents from the Mesozoic through the Cenozoic, and review the fossil records and phylogenies of each of Madagascar's mammalian groups in an attempt to estimate the minimum number of crossings necessary to produce the island's current faunal composition. Probable monophyletic origins for each major group, and thus a smaller rather than a larger number of crossings of the Mozambique Channel, imply that this water barrier has acted as a powerful filter; so powerful that it is unclear whether any crossings would have been possible without some form of subaerial connection, however ephemeral, at least from time to time during the Tertiary. Clarification of how Madagascar's terrestrial mammal fauna may have originated is thus as likely to emerge from the geology of the seafloor surrounding the island as it is to come from the fossil record or from the internal and external relationships of its various components. PMID:17053332

  1. Evidence for rodent-common and species-typical limb and digit use in eating, derived from a comparative analysis of ten rodent species.

    PubMed

    Whishaw, I Q; Sarna, J R; Pellis, S M

    1998-11-01

    Order Rodentia comprises a vast portion of mammalian species (1814 species), which occupy extremely diverse habitats requiring very distinct motor specializations (e.g. burrowing, hopping, climbing, flying and swimming). Although early classification of paw use ability suggests rodents are impoverished relative to primates and make little use of their paws, there have been no systematic investigations of paw use in rodents. The present study was undertaken to describe limb/paw movements in a variety of common rodents. The movements used for handling sunflower seeds and other foods were videorecorded and analyzed in the guinea pig (Cavia porcellus), Mongolian gerbil (Meriones unguiculatus), Syrian hamster (Mesocricetus auratus), laboratory mouse (Mus musculus), laboratory rat (Rattus norvegicus), gray squirrel (Sciurus carolinensis), red squirrel (Tamiasciurus hudsonicus), Richardson's ground squirrel (Spermophilus richardsonni), prairie dog (Cynomus parvidens), and Canadian beaver (Castor americanus). The results suggested five order-common movements of food handling: (1) locating food by sniffing, (2) grasping food by mouth, (3) sitting back on the haunches to eat, (4) grasping the food using an elbow-in movement, and (5) manipulate the food with the digits. Different species displayed species-typical specializations including (1) bilateral grasping with the paws (gerbil), (2) unilateral grasping with a paw (beaver), (3) unilateral holding (ground squirrels), (4) various grip and digit postures (all species), (5) unilateral object removal from the mouth (gerbil), (6) bilateral thumb holding (squirrels), and (7) simultaneous holding/manipulation of two objects (squirrels). Only the guinea pig did not handle food with its paws, suggesting its behavior is regressive. The existence of a core pattern of paw and digit use in rodents suggests that skilled limb and paw movements originate at least with the common ancestors of the rodent, and likely the common ancestor to rodent and primate lineages, while species-typical movements suggest specialization/regression of limb use has occurred in a number of mammalian orders. PMID:9821545

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

    PubMed

    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. PMID:24838257

  3. A First Generation Comparative Chromosome Map between Guinea Pig (Cavia porcellus) and Humans.

    PubMed

    Romanenko, Svetlana A; Perelman, Polina L; Trifonov, Vladimir A; Serdyukova, Natalia A; Li, Tangliang; Fu, Beiyuan; O'Brien, Patricia C M; Ng, Bee L; Nie, Wenhui; Liehr, Thomas; Stanyon, Roscoe; Graphodatsky, Alexander S; Yang, Fengtang

    2015-01-01

    The domesticated guinea pig, Cavia porcellus (Hystricomorpha, Rodentia), is an important laboratory species and a model for a number of human diseases. Nevertheless, genomic tools for this species are lacking; even its karyotype is poorly characterized. The guinea pig belongs to Hystricomorpha, a widespread and important group of rodents; so far the chromosomes of guinea pigs have not been compared with that of other hystricomorph species or with any other mammals. We generated full sets of chromosome-specific painting probes for the guinea pig by flow sorting and microdissection, and for the first time, mapped the chromosomal homologies between guinea pig and human by reciprocal chromosome painting. Our data demonstrate that the guinea pig karyotype has undergone extensive rearrangements: 78 synteny-conserved human autosomal segments were delimited in the guinea pig genome. The high rate of genome evolution in the guinea pig may explain why the HSA7/16 and HSA16/19 associations presumed ancestral for eutherians and the three syntenic associations (HSA1/10, 3/19, and 9/11) considered ancestral for rodents were not found in C. porcellus. The comparative chromosome map presented here is a starting point for further development of physical and genetic maps of the guinea pig as well as an aid for genome assembly assignment to specific chromosomes. Furthermore, the comparative mapping will allow a transfer of gene map data from other species. The probes developed here provide a genomic toolkit, which will make the guinea pig a key species to unravel the evolutionary biology of the Hystricomorph rodents. PMID:26010445

  4. Nuclear organization and morphology of cholinergic, putative catecholaminergic and serotonergic neurons in the brain of the Cape porcupine (Hystrix africaeaustralis): increased brain size does not lead to increased organizational complexity.

    PubMed

    Limacher, Aude'marie; Bhagwandin, Adhil; Fuxe, Kjell; Manger, Paul R

    2008-09-01

    The distribution, morphology and nuclear organization of the cholinergic, putative catecholaminergic and serotonergic systems within the brain of the Cape porcupine (Hystrix africaeaustralis) were identified following immunohistochemistry for choline acetyltransferase, tyrosine hydroxylase and serotonin. The aim of the present study was to investigate possible differences in the complement of nuclear subdivisions of these systems in the Cape porcupine in comparison with previous studies of these systems in other rodents. The Cape porcupine is the largest rodent in which these systems have been examined and has an adult body mass of 10-24kg and an average brain mass of approximately 37g, around 15 times larger than the laboratory rat. The Cape porcupines were taken from the wild and while these differences, especially that of mass, may lead to the prediction of a significant difference in the nuclear organization or number within these systems, all the nuclei observed in all three systems in the laboratory rat and in other rodents had direct homologues in the brain of the Cape porcupine. Moreover, there were no additional nuclei in the brain of the Cape porcupine that are not found in the laboratory rat or other rodents studied and vice versa. It is noted that the medial septal nucleus of the Cape porcupine appeared qualitatively to have a reduced number of neurons in comparison to the laboratory rat and other rodents. The locus coeruleus of the laboratory rat differs in location to that observed for the Cape porcupine and several other rodent species. The Cape porcupine is distantly related to the laboratory rat, but still a member of the order Rodentia; thus, changes in the organization of these systems appears to demonstrate a form of constraint related to the phylogenetic level of the order. PMID:18472246

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

    PubMed

    de Thoisy, B; Michel, J C; Vogel, I; Vié, J C

    2000-10-01

    Blood smears of 1,353 free-ranging mammals (35 species) and 112 reptiles (31 species) from French Guiana were examined for hemoparasites. Parasites from 3 major groups were recorded: Apicomplexa (including hemogregarines, piroplasms, and Plasmodium spp.), Trypanosomatidae, and Filaroidea. Fifty percent of the individuals (86% of the species) were infected by parasites from at least 1 group. Hemogregarines, identified as Hepatozoon sp., infected numerous snakes with high prevalences (30-100%); infection is reported for the first time in 5 host genera of snakes: Clelia, Oxybelis, Pseustes, Rhinobotryum, and Bothriopsis. Infections were also observed in 4 marsupial species and 1 rodent. Hepatozoon spp. recorded in Didelphis albiventris (Marsupialia) and Coendou prehensilis (Rodentia) may be new species. Plasmodium sp. were observed in 2 snake species, Dipsas indica (Colubridae) and Bothrops atrox (Viperidae). Plasmodium brasilianum was recorded in all 5 primate species examined. Piroplasms were observed in all mammal orders except primates. Large terrestrial rodents were the main hosts of members of the Babesidae; 42% of Myoprocta acouchy, 36% of Dasyprocta agouti, and 44% of Agouti paca were infected. Trypanosomes were common in mammals and were recorded in 70% of the examined genera. Trypanosoma cruzi-like infections were reported in 21 mammal species, including sloths, rodents, carnivores, and primates. Microfilariae were also widespread, with higher prevalences in sloths, anteaters, and porcupines (>40% of the individuals infected) and in tamarins (95% infected). This survey highlights some potential anthropozoonotic risks due to the recent further evidence of Plasmodium brasilianum and P. malariae as a single species and to the increased diversity of hosts for Trypanosoma cruzi. PMID:11128476

  6. Faster speciation and reduced extinction in the tropics contribute to the Mammalian latitudinal diversity gradient.

    PubMed

    Rolland, Jonathan; Condamine, Fabien L; Jiguet, Frederic; Morlon, Hélène

    2014-01-01

    The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals) peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas) reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha), high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha), or both (Chiroptera and Rodentia). Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the "out of the tropics" hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern. PMID:24492316

  7. Dengue infection in neotropical forest mammals.

    PubMed

    de Thoisy, Benoît; Lacoste, Vincent; Germain, Adeline; Muñoz-Jordán, Jorge; Colón, Candimar; Mauffrey, Jean-François; Delaval, Marguerite; Catzeflis, François; Kazanji, Mirdad; Matheus, Séverine; Dussart, Philippe; Morvan, Jacques; Setién, Alvaro Aguilar; Deparis, Xavier; Lavergne, Anne

    2009-04-01

    In South America, dengue is the arbovirus-transmitted disease with the highest incidence. Unlike other arboviruses, wild mammals have no confirmed role in the cycle of dengue in the neotropics, although serological studies have suggested a possible secondary amplification cycle involving mammals other than nonhuman primates. In French Guiana, where all four serotypes (DENV-1, DENV-2, DENV-3, DENV-4) are present, the disease is endemic with outbreak events. To determine whether wild mammals can be infected by DENV, rodents, marsupials, and bats were captured over several periods, from 2001 to 2007, at two sites. The first location is a secondary forest surrounded by an urban area where dengue is endemic. The second location is a forest edge site where the disease has not yet emerged. A total of 10,000 trap-nights were performed and 616 mammals were captured. RNAs representing the four DENV serotypes were detected at both sites by reverse-transcriptase polymerase chain reaction in the livers and/or sera of 92 mammals belonging to 14 out of 32 species distributed among all the orders investigated: Rodentia (33 positive/146 tested), Marsupialia (40/318), and Chiroptera (19/152). Sequence analyses of a portion of the capsid and premembrane junction revealed that mammal strains of DENV-1, DENV-2, DENV-3, and DENV-4 had only 92.6%, 89%, 95%, and 95.8% identity, respectively, with strains circulating in the human population during the same periods. Regarding DENV-2, strains related (99% identity) to those responsible for an epidemic event in humans in French Guiana concurrent to the capture sessions were also evidenced, suggesting that wild mammals in edge habitats can be infected by circulating human strains. Our results demonstrate, for the first time, that neotropical wild mammals can be infected with dengue virus. The question of whether mammals maintain DENV in enzootic cycles and can play a role in its reemergence in human populations remains to be answered. PMID:18945183

  8. Dung beetles (Coleoptera: Scarabaeidae) attracted to dung of the largest herbivorous rodent on earth: a comparison with human feces.

    PubMed

    Puker, Anderson; Correa, César M A; Korasaki, Vanesca; Ferreira, Kleyton R; Oliveira, Naiara G

    2013-12-01

    The capybara, Hydrochoerus hydrochaeris (L.) (Rodentia: Caviidae), is the largest herbivorous rodent on Earth and abundant in the Neotropical region, which can provide a stable food source of dung for dung beetle communities (Coleoptera: Scarabaeidae: Scarabaeinae). However, the use of capybara dung by dung beetles is poorly known. Here, we present data on the structure of the dung beetle community attracted to capybara dung and compare with the community attracted to human feces. Dung beetles were captured with pitfall traps baited with fresh capybara dung and human feces in pastures with exotic grass (Brachiaria spp.), patches of Brazilian savanna (Cerrado), and points of degraded riparian vegetation along the Aquidauana river in Anastácio and Aquidauana, Mato Grosso do Sul, Brazil. In traps baited with human feces, 13,809 individuals of 31 species were captured, and in those baited with capybara dung 1,027 individuals belonging to 26 species were captured. The average number of individuals and species captured by the traps baited with human feces was greater than for capybara dung in all habitats studied. Composition of the communities attracted to human feces and capybara dung formed distinct groups in all habitats. Despite the smaller number of species and individuals captured in capybara dung when compared with human feces, capybara dung was attractive to dung beetles. In Brazil, the legalization of hunting these rodents has been debated, which would potentially affect the community and consequently the ecological functions performed by dung beetles that use the feces of these animals as a resource. In addition, the knowledge of the communities associated with capybaras may be important in predicting the consequences of future management of their populations. PMID:24468553

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

    PubMed Central

    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

  10. Preliminary inventory of mammals from Yurubí National Park, Yaracuy, Venezuela with some comments on their natural history.

    PubMed

    García, Franger J; Delgado-Jaramillo, Mariana; Machado, Marjorie; Aular, Luis

    2012-03-01

    In Venezuela, mammals represent an important group of wildlife with high anthropogenic pressures that threaten their permanence. Focused on the need to generate baseline information that allows us to contribute to document and conserve the richness of local wildlife, we conducted a mammalogical inventory in Yurubí National Park, located in Yaracuy State in Venezuela. We carried out fieldworks in three selected vegetation types: an evergreen forest at 197m, a semi-deciduous forest ranging between 100-230m, and a cloud forest at 1 446m. We used Victor, Sherman, Havahart and pitfall traps for the capture of small non-volant mammals and mist nets for bats. In addition, we carried out interviews with local residents and direct-indirect observations for medium-large sized mammals. At least 79 species inhabit the area, representing 28% of the species recorded for the North side of the country. Chiroptera (39 spp.), Carnivora (13 spp.) and Rodentia (9 spp.) were the orders with the highest richness, as expected for the Neotropics. The evergreen forest had the greatest species richness (n=68), with a sampling effort of 128 net-hours, 32 bucket-days, 16 hours of observations, and three persons interviewed, followed by cloud forest (n=45) with 324 net-hours, 790 traps-night, 77 bucket-days, 10 hours of observations, and one person interviewed. The lowest richness value was in the semi-deciduous forest (n=41), with 591 traps-night, 15 net-hours, 10 hours of observations and three persons interviewed. Data and observations obtained in this inventory (e.g., endemism, species known as "surrogate species" threatened in Venezuela) give an important role at the Yurubí National Park in the maintenance and conservation of local ecosystems and wildlife, threatened by human pressures in the Cordillera de la Costa. PMID:22458239

  11. Threat Diversity Will Erode Mammalian Phylogenetic Diversity in the Near Future

    PubMed Central

    Jono, Clémentine M. A.; Pavoine, Sandrine

    2012-01-01

    To reduce the accelerating rate of phylogenetic diversity loss, many studies have searched for mechanisms that could explain why certain species are at risk, whereas others are not. In particular, it has been demonstrated that species might be affected by both extrinsic threat factors as well as intrinsic biological traits that could render a species more sensitive to extinction; here, we focus on extrinsic factors. Recently, the International Union for Conservation of Nature developed a new classification of threat types, including climate change, urbanization, pollution, agriculture and aquaculture, and harvesting/hunting. We have used this new classification to analyze two main factors that could explain the expected future loss of mammalian phylogenetic diversity: 1. differences in the type of threats that affect mammals and 2. differences in the number of major threats that accumulate for a single species. Our results showed that Cetartiodactyla, Diprotodontia, Monotremata, Perissodactyla, Primates, and Proboscidea could lose a high proportion of their current phylogenetic diversity in the coming decades. In contrast, Chiroptera, Didelphimorphia, and Rodentia could lose less phylogenetic diversity than expected if extinctions were random. Some mammalian clades, including Marsupiala, Chiroptera, and a subclade of Primates, are affected by particular threat types, most likely due solely to their geographic locations and associations with particular habitats. However, regardless of the geography, habitat, and taxon considered, it is not the threat type, but the threat diversity that determines the extinction risk for species and clades. Thus, some mammals might be randomly located in areas subjected to a large diversity of threats; they might also accumulate detrimental traits that render them sensitive to different threats, which is a characteristic that could be associated with large body size. Any action reducing threat diversity is expected to have a significant impact on future mammalian phylogeny. PMID:23029443

  12. Chagas disease: control, elimination and eradication. Is it possible?

    PubMed

    Coura, José Rodrigues

    2013-12-01

    From an epidemiological point of view, Chagas disease and its reservoirs and vectors can present the following characteristics: (i) enzooty, maintained by wild animals and vectors, with broad occurrence from southern United States of America (USA) to southern Argentina and Chile (42ºN 49ºS), (ii) anthropozoonosis, when man invades the wild ecotope and becomes infected with Trypanosoma cruzi from wild animals or vectors or when the vectors and wild animals, especially marsupials, invade the human domicile and infect man, (iii) zoonosis-amphixenosis and exchanged infection between animals and humans by domestic vectors in endemic areas and (iv) zooanthroponosis, infection that is transmitted from man to animals, by means of domestic vectors, which is the rarest situation in areas endemic for Chagas disease. The characteristics of Chagas disease as an enzooty of wild animals and as an anthropozoonosis are seen most frequently in the Brazilian Amazon and in the Pan-Amazon region as a whole, where there are 33 species of six genera of wild animals: Marsupialia, Chiroptera, Rodentia, Edentata (Xenarthra), Carnivora and Primata and 27 species of triatomines, most of which infected with T. cruzi . These conditions place the resident populations of this area or its visitors - tourists, hunters, fishermen and especially the people whose livelihood involves plant extraction - at risk of being affected by Chagas disease. On the other hand, there has been an exponential increase in the acute cases of Chagas disease in that region through oral transmission of T. cruzi , causing outbreaks of the disease. In four seroepidemiological surveys that were carried out in areas of the microregion of the Negro River, state of Amazonas, in 1991, 1993, 1997 and 2010, we found large numbers of people who were serologically positive for T. cruzi infection. The majority of them and/or their relatives worked in piassava extraction and had come into contact with and were stung by wild triatomines in that area. Finally, a characteristic that is greatly in evidence currently is the migration of people with Chagas disease from endemic areas of Latin America to non-endemic countries. This has created a new dilemma for these countries: the risk of transmission through blood transfusion and the onus of controlling donors and treating migrants with the disease. As an enzooty of wild animals and vectors, and as an anthropozoonosis, Chagas disease cannot be eradicated, but it must be controlled by transmission elimination to man. PMID:24402148

  13. Mitogenomic relationships of placental mammals and molecular estimates of their divergences.

    PubMed

    Arnason, Ulfur; Adegoke, Joseph A; Gullberg, Anette; Harley, Eric H; Janke, Axel; Kullberg, Morgan

    2008-09-15

    Molecular analyses of the relationships of placental mammals have shown a progressive congruence between mitogenomic and nuclear phylogenies. Some inconsistencies have nevertheless persisted, notably with respect to basal divergences. The current study has aimed to extend the representation of groups, whose position in the placental tree has been difficult to establish in mitogenomic studies. Both ML (maximum likelihood) and Bayesian analyses identified four basal monophyletic groups, Afroplacentalia (=Afrotheria: Hyracoidea, Proboscidea, Sirenia, Tenrecidea, Tubulidentata, Macroscelidea, Chrysochloridea), Xenarthra, Archontoglires (Primates, Dermoptera, Scandentia, Lagomorpha, Rodentia) and Laurasiaplacentalia (Lipotyphla, Chiroptera, Pholidota, Carnivora, Perissodactyla, Artiodactyla, Cetacea). All analyses joined Archontoglires and Laurasiaplacentalia on a common branch (Boreoplacentalia), but the relationship between Afroplacentalia, Xenarthra and Boreoplacentalia was not conclusively resolved. The phylogenomic hypothesis with a sister group relationship between Notoplacentalia (Afroplacentalia/Xenarthra) and Boreoplacentalia served as the basis for estimating the times of placental divergences using paleontologically well-supported mammalian calibration points. These estimates placed the basal placental divergence between Boreoplacentalia and Notoplacentalia at approximately 102 MYA (million years ago). The current estimates of ordinal placental divergences are congruent with recent estimates based on nuclear data, but inconsistent with paleontological notions that have placed the origin of essentially all placental orders within an interval of 5-10 MY in the early Tertiary. Among less deep divergences the estimates placed the split between Gorilla and Pan/Homo at approximately 11.5 MYA and that between Pan and Homo at approximately 8 MYA. As a consequence of these estimates, which are in accord with recent progress in primate paleontology, the earliest divergences among recent humans become placed approximately 270,000 years ago, i.e. approximately 100,000 years earlier than the traditional age of "Mitochondrial Eve". Comparison between the two new mt genomes of Hylomys suillus (short-tailed gymnure) patently demonstrates the inconsistency that may exist between taxonomic designations and molecular difference, as the distance between these two supposedly conspecific genomes exceeds that of the three elephantid genera Elephas, Mammuthus and Loxodonta. In accordance with the progressive use of the term Placentalia for extant orders and extinct taxa falling within this group we forward new proposals for the names of some superordinal clades of placental mammals. PMID:18590805

  14. Evolution of Spatially Coexpressed Families of Type-2 Vomeronasal Receptors in Rodents

    PubMed Central

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

    2015-01-01

    The vomeronasal organ (VNO) is an olfactory structure for the detection of pheromones. VNO neurons express three groups of unrelated G-protein-coupled receptors. Type-2 vomeronasal receptors (V2Rs) are specifically localized in the basal neurons of the VNO and are believed to sense protein pheromones eliciting specific reproductive behaviors. In murine species, V2Rs are organized into four families. Family-ABD V2Rs are expressed monogenically and coexpress with family-C V2Rs of either subfamily C1 (V2RC1) or subfamily C2 (V2RC2), according to a coordinate temporal diagram. Neurons expressing the phylogenetically ancient V2RC1 coexpress family-BD V2Rs or a specific group of subfamily-A V2Rs (V2RA8-10), whereas a second neuronal subset (V2RC2-positive) coexpresses a recently expanded group of five subfamily-A V2Rs (V2RA1-5) along with vomeronasal-specific Major Histocompatibility Complex molecules (H2-Mv). Through database mining and Sanger sequencing, we have analyzed the onset, diversification, and expansion of the V2R-families throughout the phylogeny of Rodentia. Our results suggest that the separation of V2RC1 and V2RC2 occurred in a Cricetidae ancestor in coincidence with the evolution of the H2-Mv genes; this phylogenetic event did not correspond with the origin of the coexpressing V2RA1-5 genes, which dates back to an ancestral myomorphan lineage. Interestingly, the evolution of receptors within the V2RA1-5 group may be implicated in the origin and diversification of some of the V2R putative cognate ligands, the exocrine secreting peptides. The establishment of V2RC2, which probably reflects the complex expansion and diversification of family-A V2Rs, generated receptors that have probably acquired a more subtle functional specificity. PMID:25539725

  15. Highly Diverse Morbillivirus-Related Paramyxoviruses in Wild Fauna of the Southwestern Indian Ocean Islands: Evidence of Exchange between Introduced and Endemic Small Mammals

    PubMed Central

    Mélade, Julien; Dietrich, Muriel; Ramasindrazana, Beza; Soarimalala, Voahangy; Lagadec, Erwan; le Minter, Gildas; Tortosa, Pablo; Heraud, Jean-Michel; de Lamballerie, Xavier; Goodman, Steven M.; Dellagi, Koussay

    2014-01-01

    ABSTRACT The Paramyxoviridae form an increasingly diverse viral family, infecting a wide variety of different hosts. In recent years, they have been linked to disease emergence in many different animal populations and in humans. Bats and rodents have been identified as major animal populations capable of harboring paramyxoviruses, and host shifting between these animals is likely to be an important driving factor in the underlying evolutionary processes that eventually lead to disease emergence. Here, we have studied paramyxovirus circulation within populations of endemic and introduced wild small mammals of the southwestern Indian Ocean region and belonging to four taxonomic orders: Rodentia, Afrosoricida, Soricomorpha, and Chiroptera. We report elevated infection levels as well as widespread paramyxovirus dispersal and frequent host exchange of a newly emerging genus of the Paramyxoviridae, currently referred to as the unclassified morbillivirus-related viruses (UMRVs). In contrast to other genera of the Paramyxoviridae, where bats have been shown to be a key host species, we show that rodents (and, in particular, Rattus rattus) are significant spreaders of UMRVs. We predict that the ecological particularities of the southwestern Indian Ocean, where small mammal species often live in densely packed, multispecies communities, in combination with the increasing invasion of R. rattus and perturbations of endemic animal communities by active anthropological development, will have a major influence on the dynamics of UMRV infection. IMPORTANCE Identification of the infectious agents that circulate within wild animal reservoirs is essential for several reasons: (i) infectious disease outbreaks often originate from wild fauna; (ii) anthropological expansion increases the risk of contact between human and animal populations and, as a result, the risk of disease emergence; (iii) evaluation of pathogen reservoirs helps in elaborating preventive measures to limit the risk of disease emergence. Many paramyxoviruses for which bats and rodents serve as major reservoirs have demonstrated their potential to cause disease in humans and animals. In the context of the biodiversity hot spot of southwestern Indian Ocean islands and their rich endemic fauna, we show that highly diverse UMRVs exchange between various endemic animal species, and their dissemination likely is facilitated by the introduced Rattus rattus. Hence, many members of the Paramyxoviridae appear well adapted for the study of the viral phylodynamics that may be associated with disease emergence. PMID:24829336

  16. The diversity of class II transposable elements in mammalian genomes has arisen from ancestral phylogenetic splits during ancient waves of proliferation through the genome.

    PubMed

    Hellen, Elizabeth H B; Brookfield, John F Y

    2013-01-01

    DNA transposons make up 3% of the human genome, approximately the same percentage as genes. However, because of their inactivity, they are often ignored in favor of the more abundant, active, retroelements. Despite this relative ignominy, there are a number of interesting questions to be asked of these transposon families. One particular question relates to the timing of proliferation and inactivation of elements in a family. Does an ongoing process of turnover occur, or is the process more akin to a life cycle for the family, with elements proliferating rapidly before deactivation at a later date? We answer this question by tracing back to the most recent common ancestor (MRCA) of each modern transposon family, using two different methods. The first method identifies the MRCA of the species in which a family of transposon fossils can still be found, which we assume will have existed soon after the true origin date of the transposon family. The second method uses molecular dating techniques to predict the age of the MRCA element from which all elements found in a modern genome are descended. Independent data from five pairs of species are used in the molecular dating analysis: human-chimpanzee, human-orangutan, dog-panda, dog-cat, and cow-pig. Orthologous pairs of elements from host species pairs are included, and the divergence dates of these species are used to constrain the analysis. We discover that, in general, the times to element common ancestry for a given family are the same for the different species pairs, suggesting that there has been no order-specific process of turnover. Furthermore, for most families, the ages of the common ancestor of the host species and of that of the elements are similar, suggesting a life cycle model for the proliferation of transposons. Where these two ages differ, in families found only in Primates and Rodentia, for example, we find that the host species date is later than that of the common ancestor of the elements, implying that there may be large deletions of elements from host species, examples of which were found in their ancestors. PMID:22923465

  17. Hantaan virus surveillance targeting small mammals at nightmare range, a high elevation military training area, Gyeonggi Province, Republic of Korea.

    PubMed

    Klein, Terry A; Kim, Heung-Chul; Chong, Sung-Tae; Kim, Jeong-Ah; Lee, Sook-Young; Kim, Won-Keun; Nunn, Peter V; Song, Jin-Won

    2015-01-01

    Rodent-borne disease surveillance was conducted at Nightmare Range (NM-R), near the demilitarized zone in northeast Gyeonggi Province, Republic of Korea, to identify hemorrhagic fever with renal syndrome (HFRS) risks for a mountainous high-elevation (500 m) military training site. Monthly surveys were conducted from January 2008-December 2009. A total of 1,720 small mammals were captured belonging to the Orders Rodentia [Families, Sciuridae (1 species) and Muridae (7 species)] and Soricomorpha [Family, Soricidae (1species)]. Apodemus agrarius, the primary reservoir for Hantaan virus (HTNV), accounted for 89.9% (1,546) of all small mammals captured, followed by Myodes regulus (4.0%), Crocidura lasiura (3.9%), Micromys minutus (1.4%), Mus musculus (0.3%), Microtus fortis (0.2%), Apodemus peninsulae (0.2%), Tamias sibiricus (0.1%), and Rattus norvegicus (<0.1%). Three species were antibody-positive (Ab+) for hantaviruses: A. agrarius (8.2%), M. minutus (4.2%), and C. lasiura (1.5%). HTNV specific RNA was detected in 93/127 Ab+ A. agrarius, while Imjin virus specific RNA was detected in 1/1 Ab+ C. lasiura. Overall, hantavirus Ab+ rates for A. agrarius increased with weight (age) and were significantly higher among males (10.9%) than females (5.1%) (P<0.0001). High A. agrarius gravid rates during the fall (August-September) were associated with peak numbers of HFRS cases in Korea that followed high gravid rates. From 79 RT-PCR positive A. agrarius, 12 HTNV RNA samples were sequenced and compared phylogenetically based on a 320 nt sequence from the GC glycoprotein-encoding M segment. These results demonstrate that the HTNV isolates from NM-R are distinctly separated from HTNV isolated from the People's Republic of China. These studies provide for improved disease risk assessments that identify military activities, rodent HTNV rates, and other factors associated with the transmission of hantaviruses during field training exercises. PMID:25874643

  18. Evolution of alanine:glyoxylate aminotransferase 1 peroxisomal and mitochondrial targeting. A survey of its subcellular distribution in the livers of various representatives of the classes Mammalia, Aves and Amphibia.

    PubMed

    Danpure, C J; Fryer, P; Jennings, P R; Allsop, J; Griffiths, S; Cunningham, A

    1994-08-01

    As part of a wider study on the molecular evolution of alanine:glyoxylate aminotransferase 1 (AGT1) intracellular compartmentalization, we have determined the subcellular distribution of immunoreactive AGT1, using postembedding protein A-gold immunoelectron microscopy, in the livers of various members of the classes Mammalia, Aves, and Amphibia. As far as organellar distribution is concerned, three categories could be distinguished. In members of the first category (type I), all, or nearly all, of the immunoreactive AGT1 was concentrated within the peroxisomes. In the second category (type II), AGT1 was found more evenly distributed in both peroxisomes and mitochondria. In the third category (type III), AGT1 was localized mainly within the mitochondria with much lower, but widely variable, amounts in the peroxisomes. Type I animals include the human, two great apes (gorilla, orangutan), two Old World monkeys (anubis baboon, Japanese macaque), a New World monkey (white-faced Saki monkey), a lago, morph (European rabbit), a bat (Seba's short-tailed fruit bat), two caviomorph rodents (guinea pig, orange-rumped agouti), and two Australian marsupials (koala, Bennett's wallaby). Type II animals include two New World monkeys (common marmoset, cotton-top tamarin), three prosimians (brown lemur, fat-tailed dwarf lemur, pygmy slow loris), five rodents (a hybrid crested porcupine, Colombian ground squirrel, laboratory rat, laboratory mouse, golden hamster), an American marsupial (grey short-tailed opossum), and a bird (raven). Type III animals include the large tree shrew, three insectivores (common Eurasian mole, European hedgehog, house shrew), four carnivores (domestic cat, ocelot, domestic dog, polecat ferret), and an amphibian (common frog). In addition to these categories, some animals (e.g. guinea pig, common frog) possessed significant amounts of cytosolic AGT1. Whereas the subcellular distribution of AGT1 in some orders (e.g. Insectivora and Carnivora) did not appear to vary markedly between the different members, in other orders (e.g. Primates, Rodentia and Marsupialia) it fluctuated widely between the different species. Phylogenetic analysis indicates that the subcellular distribution of AGT1 has changed radically on numerous occasions during the evolution of mammals. The new observations presented in this paper are compatible with our previous demonstration of a relationship between AGT1 subcellular distribution and either present or putative ancestral dietary habit, and our previous suggestion that the molecular evolution of the AGT gene has been markedly influenced by dietary selection pressure. PMID:7813517