Study On Comprehensive Selection Index In Sanhe Cattle

Based on the breeding production and marketing system of Inner Mongolia Sanhe cattle, Bio-economic model was employed to estimate the economic values of traits in breeding goal, animal model was employed to estimate the genetic parameters, and based on the comprehensive selection index, the comprehensive selection index was established by using the economic values of traits in breeding goal and the genetic parameter. The results in this study were as follows:1. Bio-economic model was constructed to evaluate the economic values of Milk yield, Fat percentage, Protein percentage, Weaning weight, Yearling weight, Mature cow weight, Dressing Percentage, Age at first calving, Calving Interval, Calving ease was:RMB 1.96,37.52,51.44,4.41, 5.02,-5.23,72.94,-3.25,4.27,65.95.respectively. Sensitivity analysis indicated that the prices of the milk and beef were positive to economic value of Birth weight, Weaning weight, Yearling weight, Mature cow weight, Dressing Percentage, were independent to economic value of function trait, the price of feed was negative to economic value of Milk yield, Fat percentage, Protein percentage, Birth weight, Weaning weight, Yearling weight, Mature cow weight, were independent to economic value of Dressing Percentage.2. Animal model was used to evaluate the genetic parameters of breeding objectives.The genetic parameters of Milk yield, Fat percentage, Protein percentage were 0.37,0.46,0.62 respectively, and there were medium and high heritability. The genetic parameters of Birth weight, Weaning weight, Yearling weight, Mature cow weight, Dressing Percentage were0.31,0.24,0.34,0.32,0.39 respectively, and there were medium and high heritability. The genetic parameters of Age at first calving, Calving Interval, Calving ease were0.06,0.03,0.13 respectively, and there were Low heritability.3.CSI was established by using the economic values of traits and genetic parameters of the traits. CSI= 2.42MY+3.76FP+3.25PP-1.65BW+1.76WW+1.45YW-2.02MCW+3.46DP-2.34 AFC-5.03CI+4.69CE; And the accuracy of selection index was 65.14%, which could accurately eavaluate comprehensive breeding value.