The Genetic Parameter Estimation For Meat And Wool Traits In LiangShan Semi-wool Sheep

After revising pedigree by microsatellite DNA markers, the breeding data from 2000 to 2005 of nuclear breeding farm's Liangshan semi-wool sheep was used for this study. Analyzed the effect of year, birth season and sex on birth weight (BW, n=1761), weaning weight (WW, n=1578), weaning daily gain (WDG, n=1422), weaning staple length (WSL, n=909),18-month weight (18W, n=585), 18-month staple length (18SL, n=600),18-month fleece weight (18FW, n=586) and 18-month fiber diameter (18FD, n=599) by using LSMEAN; estimated the variances (covariances) and genetic parameters for these three traits by using MTDFREML.The results of LSMEAN show: year, birth season and sex significantly influence BW, WW and WDG; year, birth season significantly influence WSL, but sex has little effect on WSL; year and sex sighificantly influence BW, 18W, 18SL, 18FW, 18FD. The coefficients of variation about BW, WW, WDG, WSL,18W and 18FW are 17.06, 24.52,33.40,34.27,18.43and 16.10, higher coefficients indicate a great potential to improve for the three traits.According to the results of MTDFREML: The estimates of heritability about BW, WW, WDG, WSL, 18W,18SL,18FW and 18FD are 0.18,0.34,0.27,0.38,0.20,0.26,0.32 and 0.25, respectively.The genetic parameters of four late traits for LiangShan semi-wool Sheep were reported for the first time.Relate genetic correlation coefficients are 0.38, 0.30, -0.35, 0.70, -0.29, 0.29, -0.13, 0.15, -0.13, 0.52, 0.15, 0.14, 0.25, -0.68, 0.28, -0.58, -0.33, -0.31, -0.24, 0.83, 0.62, -0.12, 0.31, 0.42, -0.41, 0.26, 0.75, 0.47 and 0.52.Taking into account the corresponding antagonistic effect, to achieve better results choice, in the building of the early selection of index options, should deal with birth weight and weaning staple length given a higher weight, weaning weight and weaning daily gain a lower weight.