Quantitative genetics of disease resistance in different groups of Penaeus semisulcatus from preliminary controlled challenge test with Vibrio parahaemolyticus the aetiological agent of acute hepatopancreatic necrosis disease (AHPND)

Acute hepatopancreatic necrosis disease (AHPND) has caused losses to shrimp farmers worldwide owing to Vibrio parahaemolyticus (VPAHPND). Selective breeding for disease resistance of shrimp was used as an alternative strategy for disease control. Five subsamples of shrimp from 20 full-sib families were subjected to a cohabitation challenge test. Juveniles of P. semisulcatus (mean weight 2.5 +/- 0.17 g) were tested for survival after challenge with VPAHPND. Mortality in the challenge test was recorded daily, and the experiment was terminated after 96 days when the mortality ceased. Moderate heritabilities were estimated in resistance to VPAHPND based on a linear model (LM) and threshold model (TM). This indicates that disease resistance is a heritable trait, and a challenge test may serve as a basis for selection for resistance to VPAHPND in P. semisulcatus. However, further investigation is needed to confirm and quantify the additive genetic variation for resistance to VPAHPND in P. semisulcatus.