Quality Characteristics of Black Soldier Flies Produced by Different Substrates

The impact of diets containing Hermetia illucens meal on the growth, intestinal health, and microbiota of gilthead seabream (Sparus aurata)

The present study investigated the effect of replacing fishmeal (FM) with insect meal of Hermetia illucens (HI) in the diet of Sparus aurata farmed inshore on growth, gut health, and microbiota composition. Two isolipidic (18% as fed) and isoproteic (42% as fed) diets were tested at the farm scale: a control diet without HI meal and an experimental diet with 11% HI meal replacing FM. At the end of the 25-week feeding trial, final body weight, specific growth rate, feed conversion rate, and hepatosomatic index were not affected by the diet. Gross morphology of the gastrointestinal tract and the liver was unchanged and showed no obvious signs of inflammation. High-throughput sequencing of 16S rRNA gene amplicons (MiSeq platform, Illumina) used to characterize the gut microbial community profile showed that Proteobacteria, Fusobacteria, and Firmicutes were the dominant phyla of the gut microbiota of gilthead seabream, regardless of diet. Dietary inclusion of HI meal altered the gut microbiota by significantly decreasing the abundance of Cetobacterium and increasing the relative abundance of the Oceanobacillus and Paenibacillus genera. Our results clearly indicate that the inclusion of HI meal as an alternative animal protein source positively affects the gut microbiota of seabream by increasing the abundance of beneficial genera, thereby improving gut health and maintaining growth performance of S. aurata from coastal farms.

A metanalysis to evaluate the effects of substrate sources on the nutritional performance of black soldier fly larvae: implications for sustainable poultry feed

This meta-analysis presents an evaluation of substrate sources and their impact on the growth performance of black soldier fly (BSF) larva. The database, compiled from Google Scholar, PubMed, and Science Direct, focuses on data concerning substrate sources, environmental conditions, and the performance parameters of BSF. Seven types of substrates were analyzed, including Feed Waste, Manure, Fruits, Mix, Animal Source, Fermentation Residue, and Food Waste. The Feed Waste group demonstrated the highest DM content, while the highest CP content was found in the Animal Source group. Higher CP and DM content were found in larva meal from Fermentation Residues and Feed Waste diets, respectively. Higher survival rates were observed in BSF larvae fed on Feed Waste, Fermentation Residues, Food Waste, Fruits, Mix, and Manure substrates compared to Vegetable and Animal Source substrates. Fresh larval weight was lower when Manure was used as a feed substrate than in the Animal Source, Feed Waste, and Vegetable substrates. The prepupal Wet Weight was highest in BSF larvae fed on Animal Source, surpassing those fed on Fermentation Residue, Manure, and Vegetable substrates. Substrate CP content exhibited a positive relationship with fresh larva weight, prepupal wet weight, dry larval weight; larval length, mortality until prepupal, protein conversion, feed conversion ratio, food consumption, substrate reduction rate bioconversion ratio, waste reduction index, and efficiency conversion of digested feed in BSF larva. In conclusion, our findings underline that the source and composition of substrates are correlated to the nutritional composition and conversion efficiency of BSF larva meal.