Dietary supplementation of black soldier fly (Hermetica illucens) meal modulates gut microbiota, innate immune response and health status of marron (Cherax cainii, Austin 2002) fed poultry-by-product and fishmeal based diets.

Md Javed Foysal,Sanjay Kumar Gupta,Chin-Yen Tay,Ravi Fotedar

doi:10.7717/peerj.6891

Md Javed Foysal, Sanjay Kumar Gupta + Show 2 more

Open Access

https://doi.org/10.7717/peerj.6891

Copy DOI

Journal: PeerJ	Publication Date: May 21, 2019
Citations: 46	License type: CC BY 4.0

Affiliation: Curtin University, University of Western Australia

Abstract

The present study aimed to evaluate the dietary supplementary effects of black soldier fly (Hermetia illucens) (BSF) meal on the bacterial communities in the distal gut, immune response and growth of freshwater crayfish, marron (Cherax cainii) fed poultry-by-product meal (PBM) as an alternative protein source to fish meal (FM). A total of 64 marron were randomly distributed into 16 different tanks with a density of four marron per tank. After acclimation, a 60-days feeding trial was conducted on marron fed isonitrogenouts and isocalorific diets containing protein source from FM, PBM, and a combination of FM + BSF and PBM + BSF. At the end of the trial, weight gain and growth of marron were found independent of any dietary treatment, however, the two diets supplemented with BSF significantly (P < 0.05) enhanced haemolymph osmolality, lysozyme activity, total haemocyte counts, and protein and energy contents in the tail muscle. In addition, the analysis of microbiota and its predicted metabolic pathways via 16s rRNA revealed a significantly (P < 0.05) higher bacterial activity and gene function correlated to biosynthesis of protein, energy and secondary metabolites in PBM + BSF than other dietary groups. Diets FM + BSF and PBM + BSF were seen to be associated with an up-regulation of cytokine genes in the intestinal tissue of marron. Overall, PBM + BSF diet proved to be a superior diet in terms of improved health status, gut microbiota and up-regulated expression of cytokine genes for marron culture.

Highlights

Fish meal (FM) is one of the major sources of dietary protein for cultured aquatic animals, posing an increasing challenge on the reduction of feed cost and wild fish stocks (Tacon & Metian, 2008)
Effects of four different feed on marron health indices No significant (P > 0.05) Weight gain (WG) and growth rate were observed in PBM and two black soldier fly (BSF) supplemented diet (FM + BSF and PBM + BSF) compared to FM (Table 2; Dataset S2)
There was no significant change in the health indices between FM and PBM fed marron in this study, but the BSF supplemented diets resulted in significant (P < 0.05) positive effects on haemolymph osmolality (HO), serum lysozyme, protein and total haemocyte counts (THC), and the impact was more pronounced (P < 0.005) with PBM + BSF diet

Summary

Introduction

Fish meal (FM) is one of the major sources of dietary protein for cultured aquatic animals, posing an increasing challenge on the reduction of feed cost and wild fish stocks (Tacon & Metian, 2008). The black soldier fly (BSF) larvae, another alternative to FM protein source, is gaining increasing popularity for the aquaculture industry (Stamer et al, 2014). The efficacy of BSF as an alternative protein source for warm-water fish has been validated in earlier studies (Stankus, 2013; Stamer et al, 2014; Wang & Shelomi, 2017); limited data are currently available on the suitability of using BSF as alternative protein source and its supplementary effect on other sources of protein, including FM and PBM in aqua-diets (St-Hilaire et al, 2007; Kroeckel et al, 2012)

Objectives

Methods

Results

Conclusion