Effects of Morphological Traits on Body Weight in the F₅ Generation of Cyprinus carpio rubrofuscus Population

Objective  The study was carried out to explore the effects of the morphological traits on body weight for Cyprinus carpio rubrofuscus F₅ generation cultured in paddy fields.

Method  Nine growth traits including total length(X₁), body length(X₂), body height(X₃), head height(X₄), head length(X₅), caudal peduncle height(X₆), caudal peduncle length(X₇), body width(X₈)and body weight(Y)of C. carpio rubrofuscus F₅ generation cultured in paddy fields were measured. The path analysis was used to analyze the data.

Result  The body weight coefficient of variation of F₅ C. carpio rubrofuscus cultured in paddy fields was 9.39%. Stepwise multiple regression analysis results showed that there were two morphological traits of body width(X₈)and body length(X₂)that significantly affected body weight. Direct path coefficient and indirect path coefficient of body width were 0.617 and 0.264, and direct path coefficient and indirect path coefficient of body length were 0.403 and 0.404. The discriminant formula was Y=-231.615+71.416X₈+10.934X₂(R²=0.868).

Conclusion  The C. carpio rubrofuscus F₅ generation was bred with the growth rate and body shape as breeding indicators. The body weight coefficient of variation of F₅ generation was lower than that of control population, and the body shape of the selected offspring was more consistent. Body width and body length were the main morphological traits effecting body weight. The study results will provide basal data for further breeding of C. carpio rubrofuscus cultured in paddy fields.