Estimation Of Genetic Parameter And Genetic Trends For Growth Traits And Reproductive Traits In Subo Merino Sheep

Fine-wool sheep breeding objective in China in general to focus on improve the quality and production of wool and that of fine wool sheep in our country and wool traits genetic evaluation was more,but the fine wool sheep growth traits and reproduction traits genetic parameter estimation was less,this study based on Subo Merino sheep production performance record and breeding lambing record data,for the first time Subo Merino sheep growth traits and reproductive traits for genetic evaluation,application balance to provide theoretical basis for breeding,the breeding of the next step for the group work and provide theoretical guidance and scientific basis for breeding programmes,accelerate the process of genetic improvement of domestic ultra-fine wool sheep.The research results in this paper were as follows:(1)SAS software was used to analyze the factors affecting the growth and reproductive traits of Subo Merino sheep,results show that the ewe age had an extremely significant effect on BW(Birth Weight)and BWPS(Yearling Body Weight Pre-shearing)(P<0.01),had no significant effect on ADG(Average Daily Gain)and BWPO(Yearling Body Weight Post-shearing)(P > 0.05);The birth type had an extremely significant effect on the BW(P <0.01),had a significant effect on BWPO(P < 0.05),had no significant effect on BWPS and ADG(P < 0.05);The flock had an extremely significant effect on growth traits and reproductive traits(P < 0.01);The birth year had an extremely significant effect on growth traits and reproductive traits(P < 0.01);The birth month had an extremely significant effect on BWPS,ADG,BWPO(P < 0.01),had no significant effect on BW(P < 0.05).(2)DMU software was used to estimate the genetic parameters of 4 growth traits and 8reproductive traits of Subo Merino sheep by AIREML method.The heritability of growth traits of Subo Merino sheep ranged from 0.03 to 0.33,belonged to low to high heritability traits.The heritability of reproductive traits ranged from 0.02 to 0.22,belonged to low to medium heritability traits;BWPS and ADG were highly positive genetic correlation,NLB with GL and TLWB were highly genetic correlated,growth traits with GL and TLWB were highly positive genetic correlation.(3)DMU software and CFC software were used to analyze the genetic trend of each trait and the inbreeding coefficient of Subo Merino sheep,the results showed that BW showed a trend of first increase,then decrease and then increase with the increase of birth year,while BWPS,ADG and BWPO showed a trend of decline before 2016,and showed a trend of sharp increase from 2016 to now.The reproductive traits of GL1,NLB1,LMWLB1 and TLWB1 first increased and then decreased,and then increased from2015 to 2017.GL showed a trend of steady rise;LMWLB showed a trend of decreasing first and then increasing.However,TNLB and TLWB showed a trend of first increase and then decrease.In 2011,the average inbreeding coefficient of the highest Subo Merino sheep population was 0.000076.The ID Number ranked breeding value of each trait was 53103,83091,53623,14272,93371,23562,43529,23549,63294,15610,43822,26510.In conclusion,this study analyzed the effect factors of growth and reproductive traits of Subo Merino sheep,estimated the genetic parameters of growth and reproductive traits,and analyzed the genetic trend of each trait,which provided a theoretical basis for improving the growth and reproductive performance of Subo Merino sheep and applying balanced breeding in the later stage.