Growth, nonspecific immunity, intestinal flora, hepatopancreas, and intestinal histological results for Litopenaeus vannamei fed with diets supplement with different animal by-products

Abstract

This study was conducted to evaluate the effects of animal by-products on growth, digestive enzymes, disease resistance, hepatopancreas, and intestinal histological outcomes in Litopenaeus vannamei. Shrimp (initial weight [g] = 0.29 ± 0.01) were fed with four types of diets for 8 weeks: control diet supplemented with 8% fish meal (FM) and three diets containing 3% FM supplemented with 5% hydrolyzed porcine mucosa (HPM), yellow mealworm meal (YMM), or enzymatic chicken liver powder (ECLM). Results showed that HPM significantly increased the weight gain and specific growth rates of shrimp (P < 0.05), and no significant differences were found among the YMM, ECLM, and control groups (P > 0.05). Muscle crude protein content significantly increased in the HPM and ECLM groups and significantly decreased in the YMM group (P < 0.05). Intestinal protease and amylase activities significantly increased in the YMM and ECLM groups (P < 0.05), and lipase activity significantly increased in the ECLM group (P < 0.05). Alkaline phosphatase activity significantly decreased in the HPM and YMM groups and significantly increased in the ECLM group (P < 0.05). Lysozyme activity significantly increased in all substitution groups, and catalase activity significantly increased in the YMM and ECLM groups (P < 0.05). Positive effects were observed in the histological results of the hepatopancreas and intestines of the YMM and ECLM groups. The results of intestinal flora analysis showed that animal by-products increased the abundance of beneficial bacteria (Sungkyunkwania) and decreased the abundance of pathogenic bacteria (Tenacibaculum), suggesting that supplementation with 5% HPM, YMM, and ECLM positively affects the growth performance of L. vannamei.