Comparison of Estimated Genetic Connectedness among Three Herds of Chinese Holstein Cattle

摘要

Estimating genetic connectedness among herds is important for the accuracy of dairy cattle genetic evaluation.When selecting between animals raised in different herds,the accuracy of their genetic evaluations can be influenced by the degree of connectedness among these herds.In this study,two methods were used to measure genetic connectedness,CR(genetic connectedness rating)and GLt(total number of direct genetic links between group),among herds from Beijing,Shanghai,and Tianjin.Genetic connectedness between the herds from Beijing and Tianjin was 23.95%,between Beijing and Shanghai was 17.10%,and between Shanghai and Tianjin it was 14.28%.Genetic connectedness between herds from Beijing and Tianjin was the highest and that between Shanghai and Tianjin was the lowest.The correlation coefficient for the two methods was 0.808.Some suggestions for improved genetic evaluation of dairy cattle were also discussed.