Analysis of the Population Characteristics and Influencing Factors of Superovulation Response Traits in Northern Chinese Holstein Cattle
[Objective]In vivo superovulation is one of the key technologies in modern dairy cattle breeding,which is of great significance for genetic improvement of dairy cattle populations.This study was conducted to reveal the phenotypic characteristics and main influencing factors in Chinese Holstein cattle,so as to provide foundation for the genetic analysis of superovulation response traits in dairy cattle.[Method]In this study,1 855 in vivo superovulation records of 1 842 Chinese Holstein cattle from 9 pastures in Ningxia and Inner Mongolia from March 2021 to August 2023 were collected,7 superovulation response traits were statistically analyzed,including total number of oocytes,number and percentage of transferable embryos,number and percentage of unfertilized oocytes,and number and percentage of degenerated embryos.The Mixed model of SAS 9.2 software was used to analyze the influencing factors on each trait,and the Pearson correlation coefficient among 7 superovulation response traits were calculated using a bivariate correlation program of SPSS 21.0 software.[Result]The average number of total oocytes and transferable embryos in Chinese Holstein cattle were 9.49 and 6.01,while the average percentage of transferable embryos was 61.95％.The average number and percentage of unfertilized oocytes were 1.50 and 17.16％,while the average number and percentage of degenerated embryos were 2.29 and 23.34％,respectively.There was varying degrees of phenotypic correlation among 7 superovulation response traits,with correlation coefficients ranging from-0.629 to 0.882.Seasons had significant influence on all traits except for the percentage of transferable embryos(P＜0.05).Hormone types and doses had significant impact on 7 superovulation response traits(P＜0.05).Semen dosage significantly affected the number of transferable embryos,degenerated embryos,and the number and percentage of unfertilized oocytes(P＜0.05).Donor age had a significant impact only on the percentage of transferable embryos and degenerated embryos(P＜0.05).[Conclusion]The phenotype of superovulation response traits in Chinese Holstein cattle was similar to the average level in global cattle.The traits were influenced by various non-genetic factors.The results laid a model foundation for further genetic analysis of superovulation response traits in dairy cattle.
Chinese Holstein cattlesuperovulationpopulation characteristicsPearson correlation
万方数据
维普
