Effects of Supplementing Low-Molecular-Weight Fish Hydrolysate in High Soybean Meal Diets on Growth, Antioxidant Activity and Non-Specific Immune Response of Pacific White Shrimp (Litopenaeus vannamei)

Özet

Supplemental effects of low-molecular-weight fish hydrolysate (LWFH) was investigated in high soybean meal (HSM)diets fed to Litopenaeus vannamei (0.44 ± 0.03 g) for 48 days. The HSM diet, containing 15% fish meal and 47% soybeanmeal, was supplemented with 0, 5, 10, 15 or 20 g $kg^{-1}$ LWFH (HSM0, HSM5, HSM10, HSM15 and HSM20). LWFHsignificantly (P < 0.05) improved growth and the highest growth was found in HSM15. Feed intake significantly increased at≥ 10 g $kg^{-1}$ LWFH, and the lowest feed conversion ratio was observed in HSM10 group. Shrimp survival significantlyincreased at ≥ 15 g $kg^{-1}$ LWFH compared to HSM0 group. Significantly higher serum peroxidase, acid phosphatase andalkaline phosphatase activities were observed in HSM20 group and total antioxidant capacity increased at ≥ 15 g $kg^{-1}$ LWFH.HSM10 group exhibited significantly higher phenoloxidase activity than HSM0, and superoxide dismutase activity enhancedin HSM5 and HSM10. Intestinal inflammatory genes expression assay showed the significant decrease of activatingtranscription factor 4 expression in HSM15 group compared to HSM0 group, and macrophage migration inhibitory factorexpression decreased significantly at 5-15 g kg-1 LWFH. To conclude, 10-15 g kg-1 LWFH in HSM diet improves growth,antioxidant activity and innate immunity.