Work

Genetic Parameter Estimation of Body Weight and VpAHPND Resistance in Two Strains of Penaeus vannamei

Year: 2025

Type: article

Abstract: Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus (VpAHPND) has severely hindered the development of the Pacific white shrimp (Penaeus vannamei) farming industry. Breeding strains resistant to VpAHPND, while also considering the growth performance, will enable farmers to achieve greater economic benefits. This study evaluated the genetic parameters of growth and VpAHPND resistance in the MK and GK strains of P. vannamei and examined the influence of genotyped female parents on the estimates of these traits under a single-parent nested mating design. VpAHPND resistance was assessed using a quantitative oral feeding method, with survival time post-infection (ST) and family survival rate at half-lethal time (SS50) as resistance indicators, and body weight at the time of death (Bw) as a measure of growth. A total of 32 families were produced in the MK strain and 44 families in the GK strain. Using the "Yellow Sea Chip No.1" with 10.0 K SNPs, 54 female parents from both strains were genotyped. In the MK strain, heritability estimates ranged from 0.428 to 0.459 for Bw and from 0.299 to 0.489 for ST and SS50. In the GK strain, heritability estimates ranged from 0.719 to 0.721 for Bw and from 0.424 to 0.512 for ST and SS50. Genetic correlations between Bw and ST ranged from 0.601 to 0.622, and between Bw and SS50 from 0.742 to 0.744 in the MK strain; in the GK strain, correlations from 0.742 to 0.744 for Bw and ST, and from 0.785 to 0.906 for Bw and SS50. The genetic correlation between ST and SS50 in both strains was not significantly different from 1 (P>0.05). Predictive accuracies for Bw, ST, and SS50 using ssGBLUP were comparable to those obtained from pBLUP in the MK strain. In the GK strain, predictive accuracies for Bw, ST, and SS50 were improved by 0.20%, 0.32%, and 0.38%, respectively, with ssGBLUP compared to pBLUP. These results suggest that both growth and VpAHPND resistance have significant breeding potential, with a positive genetic correlation between the two traits, supporting the feasibility of multi-trait selection. However, the accuracy of genetic estimates based solely on female parent genotyping was limited, indicating that future breeding program under a single-parent nested mating design should include more genotyped progeny to improve genetic accuracy.

Source: Animals

DOI: 10.3390/ani15091266