Feeding black soldier fly larvae (Hermetia illucens) reared on organic rest streams alters gut characteristics of Atlantic salmon (Salmo salar)

• Published in: Journal of Insects as Food and Feed
• Main Authors: Leeper, A., Benhaïm, D., Smárason, B., Knobloch, S., Ómarsson, K. L., Bonnafoux, T., Pipan, M., Koppe, W., Björnsdóttir, R., Øverland, M.
• Other Authors: Aquaculture and Fish Biology, School of Business and Science
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Chitin; Insects; Microbiome; Processing; Salmonids; Lax; Fiskeldi; Fiskafóður; Food Science; Insect Science; Atlantic salmon; Salmo salar
• Online Access: https://hdl.handle.net/20.500.11815/3704; https://doi.org/10.3920/JIFF2021.0105

Funding Information: The authors of this study would like to acknowledge funding from EITfood project number 18157 for Metamorphosis. Thank you to the scientific support of the analytical labs at Matís, Clara Jégousse, and NMBU Aquaculture research group for valuable feedback. Thank you also to IATA EITfood Metamorphosis project partners. Publisher Copyright: © 2022 Wageningen Academic Publishers The Atlantic salmon (Salmo salar) aquaculture industry is growing, and with it, the need to source and optimise sustainable ingredients for aquafeeds. Black soldier fly (BSF) larvae (Hermetia illucens) have received increasing research attention since they are a good source of protein that can efficiently convert a wide range of low-value organic material into valuable resources. This study investigated the impact of three differently processed BSF meals, an untreated BSF diet (BSFC+), a dechitinated BSF diet (BSFC-) and a fermented BSF diet (BSFC+P+) at a 10% inclusion level replacing fish meal in a fish meal control (FM) and a marine and soy protein concentrate based control diet (SPC). Growth performance, gut microbiome and gut histology of salmon fry was assessed. The inclusion and processing methods of BSF showed no adverse impacts on either growth performance or gut histology. However, the gut microbiome of fish was significantly altered by both the protein source and the processing method of the BSF larvae. Fish fed BSFC+, had an increased diversity and evenness of the community compared with conventional protein sources alone, and compared with the other BSF processing methods. However, control diets had a greater presence of lactic acid bacteria and genera associated with faster growing hosts. Fish fed BSF had a high relative abundance of the genus, Exiguobacterium, a chitin-degrading bacterium and in BSFC+P+ fed fish this bacterium completely dominated the community, indicating the presence of dysbiosis. Future studies should determine, why Exiguobacterium has dominated the community for the BSFC+P+ diet, ...