Comparison of unique Dong Tao chickens from Vietnam and Thailand: genetic background and differences for resource management

Abstract

Background Rare Dong Tao (DT) chickens are a unique and highly productive poultry breed introduced from Vietnam to Thailand ~ 30 years ago. It has a very peculiar appearance, including enormously enlarged feet with reddish scales, and considered local and culturally significant to both countries. Their adaptability and distinct genetic traits have attracted global interest, underscoring their potential for breeding programs and a need for their thorough genetic makeup assessment. Objective To assess the genetic diversity and differentiation within the Dong Tao chicken breed, comparing two populations introduced in Thailand with a native population in Vietnam. Methods Three Dong Tao chicken populations from Thailand and Vietnam—along with 54 other indigenous, local chicken, and red junglefowl populations from Thailand, were analyzed using 28 microsatellite markers. Result High genetic variability and low inbreeding levels were observed in these populations, indicating their effective management despite historical bottlenecks. Genetic similarities between DT-U and DT-HY and indigenous breeds, as well as the closer alignment of DT-L with red junglefowl, highlighted existing introgression and adaptation processes. Two markers, MCW0098 and MCW0216, showed a variation pattern due to potential impact of directional selection, possibly driven by environmental adaptation pressures. These findings emphasize the importance of DT chickens as genetic resources for breeding programs that focus on climate resilience and productivity enhancement. Conclusion Dong Tao chicken shared genetic similarities with indigenous and local chicken breeds, and red junglefowl, with potential influence of directional selection driven by environmental adaptation pressures