Heritability and genetic correlation of survival in turbot(Scophthalmus maximus)

We analyzed the survival data of the offspring from 21 sires and 42 dams of turbot.The results show that the cumulative survival rates for turbot from 2 to 18 months range from 17.5% to 28.5%;main mortality occurred during months 2-5;and the highest survival rates of families were 97.9%,98.8%,99.4%,99.7% during months 2-5,5-6,6-8,8-11,and 11-18,respectively,and 99.5%,being 53.5%,23.8%,19.5%,14.9%,and 13.2% higher,respectively,than the mean values in each period.In all periods,the estimated heritabilities for survival were very low without significant difference from zero(P>0.05)(values ranged from 0.06 to 0.12),indicating low additive genetic effects.The genetic correlations of survival among families in different periods were all positive,but low in magnitude(values range from 0.03 to 0.31).Genetic correlations between long-term survival and other periods' survival had negative values(-0.06 and-0.15) and three positive values(0.16,0.12 and 0.14).Genetic correlations between survival and weight were all positive,except for survival at months 2-5 and weight at 18 months,which was not significantly negative(-0.18).

We analyzed the survival data of the offspring from 21 sires and 42 dams of turbot. The results show that the cumulative survival rates for turbot from 2 to 18 months range from 17.5% to 28.5% main mortality occurred during months 2-5; and the highest survival rates of families were 97.9%, 98.8%, 99.4%, 99.7% during months 2-5, 5-6, 6-8, 8-11, and ll-18, respectively, and 99.5%, being 53.5%, 23.8%, 19.5%, 14.9%, and 13.2% higher, respectively, than the mean values in each period. In all periods, the estimated heritabilities for survival were very low without significant difference from zero （P〉0.05） （values ranged from 0.06 to 0.12）, indicating low additive genetic effects. The genetic correlations of survival among families in different periods were all positive, but low in magnitude （values range from 0.03 to 0.31）. Genetic correlations between long-term survival and other periods＇ survival had negative values （-0.06 and -0.15） and three positive values （0.16, 0.12 and 0.14）. Genetic correlations between survival and weight were all positive, except for survival at months 2-5 and weight at 18 months, which was not significantly negative （-0.18）.