Gut microbiota of rainbow trout fed Hermetia illucens

Hermetia illucens (Diptera: Stratiomydae; H) larvae are commonly studied as aquafeed ingredient. Different dietary formulations are reported to have different effects on fish gut microbiota. The previous studies reported contradictory results regarding the effect of insect-based diets on the microbiota of salmonids and the effect of dietary full-fat insects on fish microbiota has not been addressed up to now.The aim of this study was to elucidate the effect of a diet containing full-fat H larvae meal on the gut microbiota of rainbow trout (Oncorhynchus mykiss) in comparison to a control diet containing fishmeal. Microbial DNA from pyloric caeca mucosa, pyloric intestine content, mid intestine mucosa and mid intestine content from five fish samples per diet was extracted and subjected to denaturing gradient gel electrophoresis and high-throughput sequencing (MiSeq, Illumina).