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.
