Analysis Of The Main Trait Effect And Establishment Of Breeding Model For Xuefeng Black-Bone Chicken

The purpose of this experiment is to study the breeding methods of xuefeng black-bone chicken and the best breeding model under current conditions.The breeding information of xuefeng black-bone chicken is that the white-feather xuefeng black-bone chicken has 5457measurement records for 4 generations from 0 to 3 generations,including 1365 roosters and4092 hens;the yellow-feather xuefeng black-bone chicken has 4490 measurement records for4 generations from 0 to 2 generations,including 1008 roosters and 3482 hens.The measurement records include body weight,body size,black degree,primary egg weight,age at first egg and egg production.Based on the breeding data of the two strains xuefeng black-bone chicken,We can get the fundamental experiment date.The fundamental experiment date including phenotypic correlation analysis and regression analysis,estimation of genetic parameters and calculation of breeding values.Finally,based on the data obtained,a calculation model of the comprehensive selection index was developed.The results of the test are as follows:（1）The body weight of male white-feather xuefenguefeng black-bone chicken was significantly correlated with other growth and development indexes（P<0.01）,but it was negatively correlated with breast width（P<0.01,r=-0.130）.And the highest correlation was body weight and shank length（r=0.565）among all indicators.The body weight of female white-feather xuefenguefeng black-bone chicken was significantly correlated with other growth and development indexes（P<0.01）,and the highest correlation was between body weight and shank circumference（r=0.694）,and body weight was also highly correlated with shank length（r=0.527）.The body weight of male yellow-feather xuefenguefeng black-bone chicken was significant positive correlations with other growth and development indexes（P<0.01）,and the highest correlation was body weight and shank length（r=0.559）.Among all indexes,the highest correlation was fossil bone length and body slope length（r=0.621）.The body weight of fmale yellow-feather xuefenguefeng black-bone chicken was positive correlation with breast width（P<0.05）,and significant correlation with other indexes（P<0.01）,the highest correlation was body weight and shank length（r=0.496）.There was significant negative correlation between the egg production and age at first egg（P<0.01,r=-0.346,r=-0.359）of the two strains xuefeng black-bone chicken.（2）The regression equations of body weight,shank circumference and shank length of two of strains xuefeng black-bone chicken were y=-0.582x₁+0.005x₂-1.106（white-feather）and与y=-0.437x₁+0.006x₂-0.840（yellow-feather）,y represents body weight,x₁represents shank circumference,and x₂ represents shank length.The regression equations of age at first egg and the number of eggs laid of 280 days were y=-0.009x²+2.569x+342.380（white feather）and y=-0.008x²+2.438x+338.380（yellow feather）,y represents egg production,x represents age at first egg.The fitting effect of other equations was not ideal.（3）The heritability of white-feather xuefeng black-born chicken was body weight（0.330）,day old weight（0.226）,fossil bone length（0.516）,body slope length（0.180）,shank circumference（0.180）,shank length（0.173）,breast width（0.308）,breast angle（0.131）,and black degree（0.168）,primary egg weight（0.199）,pin bone spacing（0.149）,age at first egg（0.144）,the egg production of 280day（0.114）;The heritability of yellow-feather xuefeng black-born chicken was body weight（0.277）,day old weight（0.171）,fossil bone length（0.519）,body slope length（0.151）,shank circumference（0.144）,shank length（0.134）,breast width（0.146）,breast angle（0.143）,and black degree（0.425）,primary egg weight（0.151）,pin bone spacing（0.364）,age at first egg（0.250）,egg production of 280day（0.209）.（4）We set up three breeding model of xuefeng black-born chicken:Model 1:I₁=0.348EBV₁^*+0.362EBV₂^*+0.177EBV₃^*+0.182EBV₄^*-0.069EBV₅^*I₂=0.348EBV₁^*+0.263EBV₂^*+0.534EBV₃^*+0.169EBV₄^*-0.314EBV₅^*Model 2:I₁=0.539EBV₁^*+0.275EBV₂^*+0.186EBV₃^*I₂=0.304EBV₁^*+0.229EBV₂^*+0.467EBV₃^*Model 3:I₁=0.743EBV₁^*+0.257EBV₂^*I₂=0.569EBV₁^*+.0431EBV₂^*I₁represents the breeding index of White-feather xuefeng black-bone chicken,I ₂represents the breeding index of yellow-feather xuefeng black-bone chicken,EBV₁^*、EBV₂^*、EBV₃^*、EBV₄^*、EBV₅^*respectively represents standardized EBV of body weight、egg production of 280day、black degree、shank length、age at first egg.