Differentiation of Meat Samples from Domestic Horses (Equus caballus) and Asiatic Wild Asses (Equus hemionus) Using a Species-Specific Restriction Site in the Mitochondrial Cytochrome b Region.

Recent studies suggest that Asiatic wild asses (Equus hemionus) are being increasingly poached in a commercial fashion. Part of the meat is believed to reach the meat markets in the capital Ulaanbaatar. To test this hypothesis, we collected 500 meat samples between February and May 2006. To differentiate between domestic horse (Equus caballus) and wild ass meat, we developed a restriction fragment length polymorphism (RFLP) assay based on the polymerase chain reaction (PCR). We amplified and sequenced a cytochrome b fragment (335 bp) and carried out a multialignment of the generated sequences for the domestic horse, the Asiatic wild ass, the domestic donkey (Equus asinus) and the Przewalski's horse (Equus ferus przewalskii). We detected a species-specific restriction site (AatII) for the Asiatic wild ass, resulting in a specific restriction fragment length polymorphism (RFLP) band pattern. This RFLP assay represents a rapid and cost-effective method to detect wild ass meat. All of the 500 meat samples we collected and analysed within this pilot project proved to be domestic horsemeat as declared by the sales people. Thus, either the assumption that wild ass meat is sold as "cheap horse meat" is wrong, or we picked the wrong markets, products or season.