DIFFERENTIAL EFFECTS OF MORPHOMETRIC TRAITS ON BODY MASS AMONG JUVENILE LARGE YELLOW CROAKERS(LARIMICHTHYS CROCEA)WITH DIFFERENT GROWTH PERFORMANCES
This study investigates the differences in body size and morphometric trait combinations between fast-growing and common-growing juvenile subgroups within the same cohort of large yellow croakers Larimichthys crocea,thereby unraveling the internal mechanisms behind their differing weight gain patterns.This research is pivotal for guiding the discovery and selective breeding of fast-growing traits in juvenile large yellow croakers.Conducted in the Xihu Port area of Xiangshan,3 000 juvenile large yellow croakers from the same cohort were randomly sampled after three months of cultivation in floating net cages and subsequently weighed.Based on body mass,a fast-growing subgroup(FG,top 5％in weight,ranging from 3.01 to 4.81 g)and a common-growing subgroup(CG,median occurrence,weight range from 1.61 to 2.33 g)were identified.Thirty individuals from each subgroup were randomly selected,and measurements were taken for body weight(BW),body length(X1),preanal length(X2),lateral line length(X3),caudal peduncle height(X4),interventral fin distance(X5),head length(X6),and head width(X7).A series of multivariate analysis methods including principal component analysis,discriminant analysis,path analysis,and partial regression analysis were employed to quantitatively assess the impact of morphometric traits on the body mass of FG and CG subgroups.The results revealed that:(1)all biological trait measurements were significantly higher in FG than in CG(P＜0.05),with the greatest coefficient of variation observed for caudal peduncle height(X4),at 30.07％for FG and 26.70％for CG;(2)two principal components with eigenvalues greater than 1 were identified,with PC1 mainly influenced by Xi,X2,and X3,and PC2 solely by X4,together explaining 83.285％of the variance.X1 was selected as the key discriminant variable,achieving a combined discrimination accuracy of 91.67％for both subgroups;(3)through path analysis,the direct effects on BW were ranked as X5＞X2＞X3 for FG,and X1＞X6＞X4＞X7 for CG,with indirect effects ranked as X2＞X3＞X5 and X7＞X6＞X1＞X4,respectively.The summed determination coefficients and multiple correlation indices were both 0.848 and 0.888;(4)partial regression analysis produced multivariate linear regression equations for estimating BW in FG and CG subgroups.These findings offer valuable insights for the identification of fast-growing genetic traits and the scientific cultivation of juvenile large yellow croakers.
large yellow croaker Larimichthys croceafast-growing subgroupcommon-growing subgroupbody massmorphometric traitsmultivariate analysis
万方数据
维普
