Black Soldier Fly (Hermetia illucens) as an Alternative to Marine Ingredients Elicits Superior Growth Performance and Resistance to Vibrio harveyi Infection for Pacific White Shrimp (Litopenaeus vannamei)

Abstract

To assess the feasibility of incorporating insect meal and oil into diets for Pacific white shrimp Litopenaeus Vannamei, a trial was conducted to measure growth and feed performance metrics within balanced iso-nitrogenous and iso-lipid (36% protein and 6% lipid) experimental diets formulated with standard commercially sources ingredients. Incremental levels of BSF larval meal (BSFM, 0.5 to 5%) were used to partially substitute the use of fishmeal (FM) in the diet. In addition, next group of dietS were designed by using incremental levels of BSF larval oil (BSFO (0.5 to 5%) with 0.5% BSFM as a reference to partially and completely replace the use of fish oil (FO) within the diet. Ten dietary treatments were evaluated as four replicates in 40 Hapa ponds assigned randomly. Shrimp of initial mean weight of 0.97 g were fed by hand over 90 days with feed intake based on an FCR of 1.5 and all parameters recorded to determine response. Inclusion of up to 5% of both BSF meal and oil improved performance with respect to growth rate and feed utilization efficiency FCR. Total hemocyte counts and lysozyme activity reflected these trends displaying advantages of BSF diet groups compared to the basal fed group of L. Vannamei. After the growth trial, a disease challenge test was undertaken using an infection model with Vibrio harveyi at a concentration of 105 CFU shrimp-1 under controlled laboratory settings. As such, several indices of health status were recorded that included hemocyte counts, lysozyme activity as well as histopathology of the hepatopancreas that is a prime indicator of the progression of disease and a reflection on health status. Insect meal and oil inclusions increased survival from 40% to 60 - 80% and in accordance, raised the immune response and improved histopathological profiles of hepatopancreas tissues.