5 | CONCLUSION
The present study demonstrated the abundant mtDNA diversity existing in HGDs, as indicated by the presence of 11 haplotypes. In summary, our results showed that the mtDNA D-loop region of HGDs had a high genetic diversity, we confirmed that Chinese donkey originated from the African wild ass after domestication, as reported in previous research, and we could clearly exclude the Asian wild ass as an ancestor of the HGD. The study has provided an empirical basis for the elucidation of the genetic structure of the maternal ancestor of Huaibei grey donkeys.