Evaluation of genetic parameters for growth and comprehensive stress tolerance traits of Litopenaeus vannamei

To enrich the growth and stress resistance database of Litopenaeus vannamei, and to provide scientific references for the genetic improvement of its growth and comprehensive stress tolerance. We took five L. vannamei populations with different genetic backgrounds as parents, among which "Xinghai 1" (GS-01-007-2017) was the core population and the other four populations were introduced from Thailand and the United States. Eighty full-sib families had been obtained through mating and 38 families finally retained. We then used multi-trait animal model and ASReml 4 software to estimate the variance components and genetic parameters of growth and comprehensive stress tolerance of L. vannamei at 105 age old under the combined stress of high salt (35), low pH (6±0.1), and high ammonia nitrogen (70 mg·L⁻¹). The results show that the heritability of growth traits was high (0.37±0.09)−(0.51±0.10), and the heritability of comprehensive stress tolerance traits was medium (0.21±0.06). The results show that it is feasible to improve the growth traits and comprehensive stress tolerance traits by breeding. The genetic correlation of growth traits (Including body mass, body length, head breastplate length, and full length of the abdomen) was generally high, ranging from (0.54±0.13)−(0.99±0.01) (P<0.01). The extremely significant correlation between growth traits shows that any growth trait could be replaced by other growth traits for indirect selection. The genetic correlation between growth traits and comprehensive stress tolerance traits was low to medium positive correlation (0.11±0.23)−(0.39±0.19), indicating that the comprehensive stress tolerance traits can also be indirectly improved when breeding with growth traits as the main selection target.