This study aimed to estimate the additive and dominance genetic variance in growth and multiple stress-tolerance traits in 7 week and 15 week Litopenaeus vannamei shrimp. Four different animal models were studied by including all or different subsets of the following effects: additive genetic effects (A), additive genetic and common environmental effects (A+C), additive genetic and dominance effects (A+D), and additive, common environmental, and dominance effects (A+D+C). Variance components were estimated using the Average Information Restricted Maximum Likelihood (AIREML) method. In general, estimates of additive genetic variance were inflated under the simple model (A) and decreased remarkably under the more complex models (A+C, A+D, and A+D+C). The genetic parameters of two-stage (7 week and 15 week shrimp) growth and multiple stress-tolerance traits were more suitable for estimation using the A+C model. The additive effects (0.311~0.754) of seven traits in 7 week shrimp were greater than the dominance effects (4.950× 10^-7~0.201), whereas the additive effects of the same seven traits in adult shrimp ranged from 7.712×10^-8 to 0.468 and the dominance effects ranged from 0.074 to 0.577. Except for survival time, carapace length, and carapace width, the additive effects of the other traits were smaller than the corresponding dominance effects. Thus, better genetic improvement of 7 week and 15 week shrimp growth and multiple-stress tolerance can be obtained with selective breeding than with cross-breeding, and better genetic improvement of 7 week shrimp growth traits can be obtained with cross-breeding than with selective breeding. Our study further enriches the database for enhancing growth and stress resistance in L. vannamei and provides reference information for growth improvement and multiple stress-resistance breeding.

中文翻译：

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南美白对虾不同年龄生长和多重胁迫的加性和显性遗传变异的估计

本研究旨在评估 7 周和 15 周凡纳滨对虾生长和多重胁迫耐受性状的加性和显性遗传变异虾。通过包括以下效应的所有或不同子集来研究四种不同的动物模型：加性遗传效应 (A)、加性遗传和共同环境效应 (A+C)、加性遗传和显性效应 (A+D) 以及加性，共同的环境和支配效应 (A+D+C)。使用平均信息限制最大似然法 (AIREML) 方法估计方差分量。一般而言，加性遗传方差的估计值在简单模型 (A) 下被夸大，而在更复杂的模型（A+C、A+D 和 A+D+C）下显着降低。两阶段（7周和15周虾）生长和多重胁迫耐受性状的遗传参数更适合使用A+C模型估计。加性效应 (0.311~0.^-7 ~0.201), 而这7个性状对成年虾的加性效应范围为7.712×10 ^-8 ~ 0.468, 显性效应范围为0.074~0.577。除存活时间、甲壳长度和甲壳宽度外，其他性状的加性效应均小于相应的显性效应。因此，与杂交育种相比，选择育种可以获得更好的7周龄和15周龄虾生长和多重胁迫耐受性的遗传改良，并且杂交育种可以获得比选择育种更好的7周龄虾生长性状的遗传改良。配种。我们的研究进一步丰富了增强南美白对虾生长和抗逆性的数据库为促生长和多重抗逆育种提供参考资料。