Analysis Of The Progress Of Generational Breeding Of Tianfu Blue-shelled Chickens

In recent years,with the continuous improvement of people’s material standard of living,the consumption of egg products has been transformed from quantity growth to quality growth,bule shell eggs and other characteristic eggs are more and more favored by consumers.The breed of blue-shelled chickens is a characteristic local poultry of our country.It is characteristic of producing the egg with green shell color.Bule shell egg is not only unique in color,but has higher nutritional value.Since 2018,the poultry breeding team of Sichuan Agricultural Univer-sity has carried out the breeding work of new varieties with characteristics of Tianfu blue-shelled chickens.Among them,TF-G02 strains have outstanding production traits,such as high bule shell egg rate,high laying rate and long laying peak duration.In order to further guide the generation selection of TF-G02 line of Tianfu blue-shelled chickens,this study analyzed the progress of population selection,growth and development,laying performance,hatching per-formance and egg quality traits in three generations of TF-G02 line,and evaluated the genetic parameters of the main breeding traits in the third generation of TF-G02 line and fitted the growth curve and laying curve.The results provide important reference for exploring the ge-netic potential of TF-G02 series and improving its production performance continuously.The main results of this experiment are as follows:1.The retention number and proportion of TF-G02 strain of Tianfu blue-shelled chickens increased with the increase of generations,and the number and proportion of chickens conform-ing to the breeding target and strain characteristics were gradually increased;Among the related indexes of hatching performance,the healthy chick rate of the third generation reached 98.49%,which was 0.50%higher than that of the first generation.2.The weight of hens of TF-G02 strain of Tianfu blue-shelled chickens increased signifi-cantly during the breeding period,and the weight of 3rd generation hens was 1101.00 g at 17weeks of age,which was 63 g higher than that of 1st generation.At 21 weeks of age,the weight of the 3rd generation hens reached 1328.63 g,which was 74.13 g more than that of the 1st generation.The final retention rate of male hens in the third generation reached 87.99%and88.89%,respectively,which increased by 3.11%and 3.39%compared with the first generation.3.The opening date of the 3rd generation of TF-G02 was 7 days earlier than that of the 1st generation,and the opening weight was 1319.36 g,158.81 g less.The total number of eggs at300 days of age was 116.63,an increase of 16.34.The peak of egg production increased from78.64%to 82.18%in the first generation,and the time of weekly egg production rate above 79%was extended to 5 weeks.The egg weight,eggshell strength and yolk ratio of generation 3 at30 weeks and 300 days of age increased by 2.60 g and 2.24 g,0.67 kg/cm~2 and 0.58 kg/cm~2,2.84%and 3.10%,respectively,compared with generation 1.4.The heritability of growth traits of TF-G02 line of Tianfu blue-shelled chickens ranged from 0.15 to 0.38,and the repeatability ranged from 0.18 to 0.40.The heritability and repeata-bility of laying traits ranged from 0.28 to 0.45,and 0.26 to 0.44.The genetic and phenotypic correlations of growth traits and laying traits were highly consistent.5.Logistic,Gompertz and Von Bertalanffy nonlinear growth curve models were used to fit the 1-21 week growth curves of TF-G02 strain of Tianfu blue-shelled chickens The Gompertz model had the best fitting effect for all the three generations,and the fitting degree was over0.997.The fitted body weight of each week is not much different from the actual measured value,which can be used as the best model for weight breeding.6.Wood model,cell model and Yangning model were used to fit the laying curves of TF-G02 strain at 20 to 43 weeks.The best fitting degree of Yangning model in the three generations was 0.964 to 0.988,and the fitted laying rates at each week were not much different from the measured values.It can be used as the best model for egg production and breeding.In conclusion,after three generations of breeding,TF-G02 strain of Tianfu blue-shelled chickens has achieved remarkable results in population retention,hatching performance,growth performance,laying performance and egg quality,basically achieving the expected re-sults.By estimating the genetic parameters of the main production traits of Tianfu green shell laying hens,the genetic potential of Tianfu blue-shelled chickens was fully explored,which provided an important reference for the subsequent breeding of Tianfu green shell laying hens.In addition,the Gompertz model and Yangning model can be used to fit the growth performance and laying rule,which provides a scientific basis for the optimization of feeding management plan.