RESUMO
Since the second Indochina war, habitat destruction and overhunting has resulted in fragmentation of the remaining populations of Bos javanicus and B. gaurus. Nowadays, both species are in serious danger, especially the gaur. In Vietnam, where these species have become almost impossible to capture in the wild, non-invasive investigations are the only feasible approach to obtain data on populations. However, non-invasive derived DNA, especially in tropical areas, is usually characterized by low concentrations, poor quality and/or contamination from alien DNA. To assist in tropical conservation management, baseline information is provided here on assessing the reliability of species identification, molecular sexing and microsatellite genotyping using fecal DNA from B. gaurus and B. javanicus. For species identification using bovine fecal samples, cytochrome b fragment between positions 867 and 1140 was found to contain species diagnostic sites, which distinguishes the four species encountered in the region: B. gaurus, B. indicus, B. javanicus and B. taurus. For sex determination, primers were initially tested on DNA obtained from blood. Then, these primers were successfully used on DNA derived from fecal material. Finally, we also evaluate the feasibility of non-invasive microsatellite genotyping on fecal samples collected in Vietnamese nature reserves. The results presented here improve on current molecular methods based on fecal material obtained from tropical areas.
