Genetic gain in dairy cattle populations is increased using sexed semen in commercial herds.

摘要: Using stochastic simulation, the effect of using sexed semen to cow dams (CD) in a dairy cattle breeding scheme, with or without use multiple ovulation and embryo transfer (MOET) bull (BD), on annual genetic gain at population level was examined. Three levels were combined three MOET: no semen, best CD all heifers, MOET, MOET BD randomly 20% BD. In total, nine scenarios compared. The simulated monitored for 30 years included 450 herds 100 cows each. Each year 50 young bulls (YB), 10 active sires 215 selected linear unbiased prediction estimated values by truncation selection across population, YB tested within population. Use alone gave positive increase 2.1% when used 2.7% but only latter statistically significant. increased caused larger contribution from together 1.8-2.5% compared schemes Performing enables offspring high Mendelian deviations, which gain. decreased lag between 12-14% 6% heifers. decrease is intensity dams.