Curve fitting analysis for laying rate and total egg number of the third generation of Xinyi Huaixiang chicken C strain

ObjectiveThe present study investigated the change rule of laying rate and egg production of the third generation of Xinyi Huaixiang chicken C strain(light yellow feather circled around the neck),in order to provide scientific reference for improving laying performance of Huaixiang chicken.Method Laying rate and total egg number of the third generation of Xinyi Huaixiang chicken C strain at 19-52 week age were collected.Four models,namely Wood,YangNing,McMillan and cubic equation,were adopted to fitting analysis on laying rate;and Logistic,Von Bertalanffy and Compertz were employed in fitting analysis on total egg number.The parameters and fitting degree(R2) of these models were calculated.ResultR2 of Yang-Ning was the highest(0.988),followed by McMillan(0.976),Wood(0.833) and cubic equation (0.733).R2 of Logistic,Compertz and Von Bertalanffy for total egg number was 0.988,0.995 and 0.998 respectively.In Yang-Ning,the highest laying rate was 73.85%,which was the closest to the observed value(73.66%).In Von Bertalanffy,the maximum egg production was 128.96,which was the closest to the observed value (131.62) compared to the values of Logistic (125.56) and Gompertz (127.88).ConclusionYang-Ning and Von Bertalanffy have the optimum fitting effects on laying rate and total egg number of the third generation of Xinyi Huaixiang chicken C strain,which can be used for prediction of laying rate and egg production of Xinyi Huaixiang chickens.