Twenty-six half-sib groups (53 full-sib families) of turbot,Scophthalmus maximus Linnaeus, were obtained by artificial insemination. We measured growth in the offspring (40-50 individuals/family) and subjected the...Twenty-six half-sib groups (53 full-sib families) of turbot,Scophthalmus maximus Linnaeus, were obtained by artificial insemination. We measured growth in the offspring (40-50 individuals/family) and subjected them to a thermal tolerance challenge over a period of 34 d. There was no significant difference in daily mor-tality (range: 0.580%-1.391%) between Days 1-13 during the thermal tolerance challenge. However, daily cumulative mortality increased rapidly between Days 14 and 29, especially on Days 15 and 16 (20.232% and 34.377%, respectively). Mortality was highest on Day 16 (14.145%). We estimated the genetic parameters using the average information restricted maximum likelihood method. We used a likelihood ratio test to evaluate the significance of effects in models with and without identity as an effect, and compared the final log-likelihoods (maximum log L). Lastly, we estimated phenotypic and genetic correlation between the up-per thermal tolerance limit (UTT) and body weight (BW). In this study, the positive phenotypic correlation was low between UTT and BW (0.093±0.029). The genetic correlation between UTT and BW was negative (-0.044±0.239). The heritability for upper thermal tolerance was low (0.087±0.032), which is of approximate-ly moderate heritability. The heritability for body weight was high (0.303±0.074). Our results suggest there is significant potential for improvement in the culture of turbot by selective breeding.展开更多
基金The Special Scientific Research Funds for Central Non-profit Institutes,Yellow Sea Fisheries Research Institutes under contract No.20603022012002the National High Technology Research and Development Program of China(863 Program) under contract No.2012AA10A408-7
文摘Twenty-six half-sib groups (53 full-sib families) of turbot,Scophthalmus maximus Linnaeus, were obtained by artificial insemination. We measured growth in the offspring (40-50 individuals/family) and subjected them to a thermal tolerance challenge over a period of 34 d. There was no significant difference in daily mor-tality (range: 0.580%-1.391%) between Days 1-13 during the thermal tolerance challenge. However, daily cumulative mortality increased rapidly between Days 14 and 29, especially on Days 15 and 16 (20.232% and 34.377%, respectively). Mortality was highest on Day 16 (14.145%). We estimated the genetic parameters using the average information restricted maximum likelihood method. We used a likelihood ratio test to evaluate the significance of effects in models with and without identity as an effect, and compared the final log-likelihoods (maximum log L). Lastly, we estimated phenotypic and genetic correlation between the up-per thermal tolerance limit (UTT) and body weight (BW). In this study, the positive phenotypic correlation was low between UTT and BW (0.093±0.029). The genetic correlation between UTT and BW was negative (-0.044±0.239). The heritability for upper thermal tolerance was low (0.087±0.032), which is of approximate-ly moderate heritability. The heritability for body weight was high (0.303±0.074). Our results suggest there is significant potential for improvement in the culture of turbot by selective breeding.