Vol. 7, Issue 2, Part A (2025)

The present study was conducted to investigate the effect of ashwagandha (Withania somnifera) root powder on immunological parameters and disease resistance to Vibrio parahaemolyticus in Penaeus vannamei (Boone, 1931). The active metabolites withanolides containing ashwagandha root powder (ARP) formulated with a 35% protein level as a different dietary concentrations viz. T₀ (Control, 0%), T₁ (2.5%), T₂ (5%) and T₃ (7.5%). Penaeus vannamei post-larvae (average weight 0.012g) were selected with a density of 20 no. in each of the 16 treatment tank and distributed in completely randomized design. The ARP feed diets in P. vannamei exhibited significantly higher values in WG, SGR (%), and PER, and significantly lower values in FCR in the treatment T₃ feed diet as compared to the control diet (0% ARP), with a significant level of p<0.05. The disease challenge test of Vibrio parahaemolyticus (0.1 ml injection) randomly selected shrimps in each tank and exhibited higher SR (%) in treatment T₃, with a significance level of p<0.05. The ARP supplemented in feed diet significantly increased the immunomodulatory levels such as Prophenoloxidase activity (PPO), Respiratory burst of superoxide anion production (NBT assay), and the total haemocyte count in haemolymph in treatment T₃ feed diet with a significance level of p<0.05. Thus, at the end of the result, the supplemented 7.5% of ARP in shrimp feed diet was interpreted without any adverse effects on growth performance and immune responses of L. vannamei.