Based on 440 skulls recently collected from two areas of the wild ass population in Mongolia, the time course of tooth eruption and replacement was investigated. The dentition pattern allows identification of age up to five years. We also conclude that annual lines in the tooth cementum can be used to determine the age in years for wild asses older than five years after longitudinal tooth sections were made with a lowspeed precision saw. The first upper incisor proved to be most suitable for age determination, although the starting time of cement deposition is different between the labial and lingual sides of the tooth. The accurate age of the wild ass can be determined from the number of annual lines and the time before the first formation of the cementum at the respective side of the tooth.
Aim Snow leopards are distributed across the mountains of 12 countries spread across 1.8 million km2 in Central and South Asia. Previous efforts to map snow leopard distributions have relied on expert opinions and modelling of presence‐only data. Expert opinion is subjective and its reliability is difficult to assess, while analyses of presence‐only data have tended to ignore the imperfect detectability of this elusive species. The study was conducted to prepare the first ever probabilistic distribution map of snow leopards across Mongolia addressing the challenge of imperfect detection. Location We conducted sign‐based occupancy surveys across 1,017 grid‐cells covering 406,800 km2 of Mongolia's potential snow leopard range. Methods Using a candidate model set of 31 ecologically meaningful models that used six site and seven sampling covariates, we estimate the probability of sites being used by snow leopards across the entire country. Results Occupancy probability increased with greater terrain ruggedness, with lower values of vegetation indices, with less forest cover, and were highest at intermediate altitudes. Detection probability was higher for segments walked on foot, and for those in more rugged terrain. Our results showed broad agreement with maps developed using expert opinion and presence‐only data but also highlighted important differences, for example in northern areas of Mongolia deemed largely unfavourable by previous expert opinion and presence‐only analyses. Main conclusions This study reports the first national‐level occupancy survey of snow leopards in Mongolia and highlights methodological opportunities that can be taken to scale and support national‐level conservation planning. Our assessments indicated that <12% of its entire land mass, and 42% of the potential snow leopard habitat in Mongolia has a high (>0.5) probability of being used by snow leopards. We emphasize the utility of occupancy modelling, which jointly models detection and site use, in achieving these goals.
Background In addition to the broad dissemination of pathogenic extended-spectrum beta-lactamase (ESBL)-producing Escherichia (E.) coli in human and veterinary medicine and the community, their occurrence in wildlife and the environment is a growing concern. Wild birds in particular often carry clinically relevant ESBL-producing E. coli. Objectives We analyzed ESBL-producing and non-ESBL-producing E. coli obtained from wild birds in Mongolia to identify phylogenetic and functional characteristics that would explain the predominance of a particular E. coli clonal lineage in this area. Methods We investigated ESBL-producing E. coli using whole-genome sequencing and phylogenetics to describe the population structure, resistance and virulence features and performed phenotypic experiments like biofilm formation and adhesion to epithelial cells. We compared the phenotypic characteristics to non-ESBL-producing E. coli from the same background (Mongolian wild birds) and genomic results to publicly available genomes. Results and Conclusion We found ESBL-producing E. coli sequence type (ST) 1159 among wild birds in Mongolia. This clonal lineage carried virulence features typical for extra-intestinal pathogenic or enterotoxigenic E. coli. Comparative functional experiments suggested no burden of resistance in the ST1159 isolates, which is despite their carriage of ESBL-plasmids. Wild birds will likely disseminate these antibiotic-resistant pathogens further during migration.
The Asiatic wild ass (Equus hemionus) is a globally endangered large mammal threatened by competition with livestock, poaching as well as habitat fragmentation and loss. Because of these environmental stresses it can be assumed that the species suff ers from lower developmental stability and that barrier eff ects could cause genetic isolation. To gain more insight into the population genetics of the Asiatic wild ass, a series of 440 skulls found in two Gobi regions of Mongolia were examined. The epigenetic variability and epigenetic distance between the samples as well as their fl uctuating asymmetry were studied by using 62 non-metric skull characters to test and evaluate possible genetic depletion, genetic isolation and the general infl uences during ontogenesis. The high epigenetic variability, I ev = 0.39 did not diff er between the two regions indicating no evidence of genetic depression. The very low, but signifi cant epigenetic divergence of MMD = 0.05 between the Dzungarian Gobi and the Southern Gobi suggests restricted connectivity. The moderate degree of fl uctuating asymmetry (FA = 0.11 -0.15) found gives no signs of reduced developmental stability. Thus, our results suggest that Asiatic wild ass from Mongolia are from genetically viable populations. Lkhagvasuren, D., Batsaikhan, N., Samiya, R., Schafberg, R., Stubbe, A., Stubbe, M. & Ansorge, H. 2015. Morphological approach to genetic variability of the Asiatic wild ass (Equus hemionus) using non-metric skull characters. Mong. J. Biol. Sci., 13(1-2): 3-12.
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