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Wild Ruminants (wild + ruminant)
Selected AbstractsAntimicrobial-resistant faecal Escherichia coli in wild mammals in central Europe: multiresistant Escherichia coli producing extended-spectrum beta-lactamases in wild boarsJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2010I. Literak Abstract Aims:, To determine the presence of antibiotic-resistant faecal Escherichia coli in populations of wild mammals in the Czech Republic and Slovakia. Methods and Results:, Rectal swabs or faeces collected during 2006,2008 from wild mammals were spread on MacConkey agar and MacConkey agar containing 2 mg l,1 of cefotaxime. From plates with positive growth, one isolate was recovered and identified as E. coli. Susceptibility to 12 antibiotics was tested using the disk diffusion method. Resistance genes, class 1 and 2 integrons and gene cassettes were detected in resistant isolates by polymerase chain reaction (PCR). Extended-spectrum beta-lactamases (ESBL) were further characterized by DNA sequencing, macrorestriction profiling and determination of plasmid sizes. Plasmid DNA was subjected to EcoRV digestion, transferability by conjugation and incompatibility grouping by multiplex PCR. The prevalence of resistant isolates was 2% in small terrestrial mammals (rodents and insectivores, nE. coli = 242), 12% in wild ruminants and foxes (nE. coli = 42), while no resistant isolates were detected in brown bears (nE. coli = 16). In wild boars (Sus scrofa) (nE. coli = 290), the prevalence of resistant isolates was 6%. Class 1 and 2 integrons with various gene cassettes were recorded in resistant isolates. From wild boars, five (2%, nrectal smears = 293) multiresistant isolates producing ESBL were recovered: one isolate with blaCTX-M-1 + blaTEM-1, three with blaCTX-M-1 and one with blaTEM-52b. The blaCTX-M-1 genes were carried on approx. 90 kb IncI1 conjugative plasmids. Conclusions:, Antibiotic-resistant E. coli occured in populations of wild mammals in various prevalences. Significance and Impact of the Study:, Wild mammals are reservoirs of antibiotic-resistant E. coli including ESBL-producing strains which were found in wild boars. [source] Humoral immunity in natural infection by tick-borne encephalitis virusJOURNAL OF MEDICAL VIROLOGY, Issue 4 2009Giulietta Venturi Abstract Tick-borne encephalitis (TBE) virus is one of the most important flaviviruses associated with neurological disease in Europe. Cross-reactive antibodies elicited by different flaviviruses can make difficult the interpretation of ELISA and hemagglutination-inhibition (HI) tests for the diagnosis of TBE. Neutralization tests, which are more specific, are not in common use because they are difficult to perform and standardize. A plaque reduction neutralization test (PRNT), optimized previously in vaccinated children, was evaluated in sera from acute cases of TBE, collected for diagnostic purposes, and from healthy human population and wild ruminants, collected for serosurvey purposes. The PRNT results were compared with the results of ELISA and HI tests. In acute TBE disease, most sera were positive for IgM antibodies by ELISA and with high HI antibody titers; neutralizing antibodies were detected in 71.4% of patients, at a very low titer (1:10 NT50) in almost all cases. Seroprevalences of 8% and 6.5% for anti-TBE ELISA antibodies were found in healthy subjects and wild ruminants, respectively. Among anti-TBE positive healthy subjects, a very low 1:10 NT50 titer was detected in 17.4% of cases, while NT80 titers ranging from 1:10 to 1:80 were detected in 65.2% of cases. Among wild ruminants, 90.9% of ELISA and HI positive samples showed a positive, ,1:10 NT80 titer. In conclusion, neutralization assays can be useful for the diagnosis and serosurveys of TBE. J. Med. Virol. 81:665,671, 2009 © 2009 Wiley-Liss, Inc. [source] The intraruminal papillation gradient in wild ruminants of different feeding types: Implications for rumen physiologyJOURNAL OF MORPHOLOGY, Issue 8 2009Marcus Clauss Abstract Browsing and grazing ruminants are thought to differ in the degree their rumen contents are stratified,which may be due to different characteristics of their respective forages, to particular adaptations of the animals, or both. However, this stratification is difficult to measure in live animals. The papillation of the rumen has been suggested as an anatomical proxy for stratification,with even papillation indicating homogenous contents, and uneven papillation (with few and small dorsal and ventral papillae, and prominent papillae in the atrium ruminis) stratified contents. Using the surface enlargement factor (SEF, indicating how basal mucosa surface is increased by papillae) of over 55 ruminant species, we demonstrate that differences between the SEFdorsal or SEFventral and the SEFatrium are significantly related to the percentage of grass in the natural diet. The more a species is adapted to grass, the more distinct this difference, with extreme grazers having unpapillated dorsal and ventral mucosa. The relative SEFdorsal as anatomical proxy for stratification, and the difference in particle and fluid retention in the rumen as physiological proxy for stratification, are highly correlated in species (n = 9) for which both kind of data are available. The results support the concept that the stratification of rumen contents varies among ruminants, with more homogenous contents in the more browsing and more stratified contents in the more grazing species. J. Morphol., 2009. © 2009 Wiley-Liss, Inc. [source] Diet composition, rumen papillation and maintenance of carcass mass in female Norwegian reindeer (Rangifer tarandus tarandus) in winterJOURNAL OF ZOOLOGY, Issue 1 2000S. D. Mathiesen Abstract The uptake of volatile fatty acids (VFAs) from bacterial fermentation of forage in the rumen is enhanced by the presence of papillae which greatly increase the surface area of the mucosa of the rumen. The degree of papillation, expressed as the surface enlargement factor (SEF), seems to be closely related to the level of microbial activity and the rate of production of VFAs in the rumen. In several species of wild ruminants the SEF decreases markedly in winter, apparently in response to a decrease in the quality and availability of forage and also, presumably, in the level of ruminal microbial activity. Contrary to expectation, however, no reduction in the rate of production of VFAs in winter has been detected in semi-domesticated reindeer at natural pasture in northern Norway. We investigated the body mass, the composition and quality of the diet and the morphology of rumen papillae in adult female reindeer free-living at natural pasture. Animals were slaughtered in matched aged groups of nine on four occasions: in autumn (September) and winter (November, February and March). The composition and quality of the diet was determined by morphological and chemical analysis of plant fragments recovered from the rumen. The carcass mass of the animals did not differ significantly between collections. The animals ate vascular plants and lichens from 37 different genera. The composition of the diet varied little between months except for the inclusion of a substantial proportion (25.8% of fragments) of lichens in March. The mean density of rumen papillae increased from 55.6 papillae/cm2 in September to 75.7 papillae/cm2 in March (P < 0.001). All other parameters, including the length and perimeter of the papillae and the SEF of the rumen, were lower in March compared with September. However, the mean SEF increased from 8.8 in February to 10.6 in March (P < 0.05), indicating increased ruminal fermentation in late winter. We propose that the increase in the SEF in March might be associated with the increase in the proportion of lichens in the diet. Lichens are highly digestible in reindeer but do not score highly in conventional analyses of diet quality owing to the unusual chemical structure of the structural carbohydrates of which they are composed. [source] Species identification of Hypoderma affecting domestic and wild ruminants by morphological and molecular characterizationMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2003D. Otranto Abstract., Cuticular structures and the sequence of the cytochrome oxidase I gene were compared for Hypoderma bovis (Linnaeus), Hypoderma lineatum (De Villers), Hypoderma actaeon Brauer, Hypoderma diana Brauer and Hypoderma tarandi (Linnaeus) (Diptera, Oestridae). Third-stage larvae of each species were examined by scanning electron microscopy revealing differences among species in the pattern and morphology of spines on the cephalic and thoracic segments, by spine patterns on the tenth abdominal segment, and by morphology of the spiracular plates. The morphological approach was supported by the molecular characterization of the most variable region of the cytochrome oxidase I (COI) gene of these species, which was amplified by polymerase chain reaction and analysed. Amplicons were digested with the unique restriction enzyme, BfaI, providing diagnostic profiles able to simultaneously differentiate all Hypoderma species examined. These findings confirm the utility of morphological characters for differentiating the most common Hypoderma larvae and reconfirm the power of the COI gene for studying insect identification and systematics. [source] | ||||||||||