The First Ancient DNA Evidence of Zebu Husbandry in Thailand During the Prehistoric Through the Historic Periods

In Southeast Asia (SEA), Bos indicus (zebu) refers to the traditional cattle, whereas Bos taurus (taurine) refers to exotic breeds imported from foreign countries. Notably, a previous study reported that all Thai cattle dating to 3500–1700 years before present (YBP) belonged to the taurine lineage. This suggests that zebu may have been introduced into Thailand at a later date, subsequently replacing the taurine population. In the present study, we analysed 26 cattle remains from nine archaeological sites across Thailand dated to between 3400 and 600 YBP. Taxonomic classification of the specimens was determined using partial D-loop sequences. DNA from four cattle remains obtained from two archaeological sites (Khao Khuram, dated to 1700–1500 YBP, and Sukhothai Historical Park, dated to 850–650 YBP) was successfully amplified and sequenced. Both phylogenetic and haplotype network analyses showed that these remains were grouped in the same haplotype as modern zebu cattle from India, China, and Cambodia. The results suggest that ancient Thai cattle belonged to the zebu lineage and that zebu cattle were introduced into Thailand from India at least 1700 years ago. Furthermore, genetic relationships suggest two potential routes of introduction into Thailand and other SEA countries via overland and maritime routes.