![]() ![]() The inbreeding coefficients were also estimated based on two datasets as well. In addition, when using LD-based pruning dataset (233,788 SNPs), we found that heterozygosity values were slightly reduced in Diqing, Zhaotong, and Dengchuan cattle, but were slightly increased in Dianzhong, Wenshan, and Dehong humped cattle. Interestingly, there existed a declining trend of genomic diversity for these native breeds from Northeastern Yunnan to Western Yunnan ( Table 2, Figure 2). Similarly, using a dataset of 233,788 SNPs, the lowest Ho (0.295) was found in Dehong humped cattle, while the highest Ho (0.360) was detected in Zhaotong cattle. Using a dataset of 604,630 SNPs, the average Ho ranged from 0.257 in Dehong humped cattle (Western Yunnan) to 0.366 in Zhaotong cattle (Northeastern Yunnan). Here we used two different datasets to assess the effect of ascertainment biases on diversity indexes of each breed. However, information on genomic diversity and admixture patterns among six Chinese indigenous cattle breeds in Yunnan is still very limited. Previous studies on Yunnan native cattle breeds focused mainly on mitochondrial diversity, origins, introgression and phylogeographic structure. As a result, it is urgent to understand their genomic background before loss or extinction. For instance, Dengchuan cattle are already on the brink of extinction, due to crossbreeding with exotic commercial breeds such as Holstein, Simmental and Shorthorn cattle. The number of some pure native breeds has been decreased from ten thousand head in the 20th century to several hundred head in present day. In recent years, the implementation of artificial insemination, together with global climate change and frequent outbreaks of emerging animal diseases, has increased the risk of loss of Yunnan native cattle breeds. ![]() ![]() In addition, these indigenous breeds exhibit excellent characteristics such as tolerance to rough feeding, good adaptability under adverse climatic conditions, and resistance to some animal diseases and parasites. It should be emphasized that Dengchuan cattle is the only one local dairy cattle breed in China with high rate of milk production. These breeds provide not only useful products such as cowhide, meat and milk to local farmers and communities, but also are used as the main means of transportation in remote villages. Article Sharing (Author Self-Archiving) PolicyĪccording to China National Commission of Animal Genetic Resources, there are six indigenous cattle breeds (Diqing, Zhaotong, Dengchuan, Dianzhong, Wenshan, and Dehong humped cattle) in Yunnan, Southwestern China.Nonruminant Nutrition and Feed Processing.Poultry and Laboratory Animal Nutrition.Ruminant Nutrition and Forage Utilization. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |