Effects of dietary supplementation of monobutyrin and tributyrin on growth, feed efficiency, innate immunity, digestibility and disease resistance of Pacific white shrimp ( Litopenaeus vannamei ) against Vibrio harveyi

Abstract

This study was conducted to evaluate the supplemental effects of esterified monobutyrin (MB) and tributyrin (TB) on growth performance, feed efficiency, digestibility, innate immunity, antioxidant status and disease resistance of Pacific white shrimp, Litopenaeus vannamei. A basal (control) experimental diet was formulated without MB or TB, and four other diets were prepared by supplementing powder forms of MB at 2 and 4 g/kg (0.2% and 0.4%) or TB at 1 and 2 g/kg (0.1% and 0.2%) (designated as MB0.2, MB0.4, TB0.1 and TB0.2, respectively). Quadruplicate groups of shrimps were hand-fed with one of the diets four times daily for 53 days. Shrimp fed MB or TB diets showed significantly higher growth performance, feed utilization, phagocytosis and glutathione peroxidase activity than shrimp fed the control diet. Increased digestibility of dietary protein, lipid and dry matter was found in shrimp fed MB- or TB-supplemented diets. Relative mRNA expression levels of IGF-binding protein and prophenoloxidase gene were significantly increased in shrimp fed MB- or TB-supplemented diets than in shrimp fed the control diet. The results of a challenge test with Vibrio harveyi showed that the disease resistance of shrimp can be significantly enhanced against V. harveyi when they were fed TB0.2 diet. The results of this study indicate that dietary supplementation of 2 g/kg MB or 1–2 g/kg TB can improve growth and feed efficiency, innate immunity, antioxidant activity, digestibility and disease resistance of L. vannamei.