Influence of black soldier fly meal on gut function

Due to its sustainability benefits and significant nutritional value, black soldier fly meal is receiving more attention as a feed ingredient for pigs, poultry and aquaculture species. However, as a team at the University of Turin and the Institute of Science of Food Production in Italy has recently demonstrated, black soldier fly meal (BSFM) can also provide positive gut benefits in weaned pigs.

Team members recently published their study, entitled ’Effects of dietary Hermetia illucens meal inclusion on cecal microbiota and small intestinal mucin dynamics and infiltration with immune cells of weaned piglets’ in the Journal of Animal Science and Biotechnology.

Gut function

It’s already well known that feed ingredients can affect intestinal microbiota, with these microbes in turn, note the study scientists, “exerting a significant influence on gut and systemic health,” as well as “nutrient processing and energy harvesting.” The researchers also note that gut microbiota and the products they produce are capable of influencing the synthesis and secretion of mucins. Mucins are the glycoproteins that coat the gut, protecting it from digestive enzymes and more, but also playing a large role in the digestion and absorption of nutrients.

Because of these facts, the team therefore investigated the effect of dietary BSFM on both gut microbiota and mucins, considering them both “to be fundamental in finding effective strategies for the improvement of pig intestinal health and feed efficiency, especially when a novel feed ingredient is tested.”

The scientists add that because piglets “especially in the postweaning period, are under great environmental pressure, thus causing a decline in their immune function, and in turn development of gut inflammation, histological analysis of the gut may also provide useful information about the health status of the intestinal barrier.”

The trial included 48 weaned piglets randomly allotted to three diets, a control diet and those with the inclusion of either 5% or 10% BSFM.

Results positive

The gut of the piglets fed BSFM diets had greater neutral mucin percentage compared to piglets fed the control diet. The scientists note that a predominance of these mucins “is considered indicative of an increased intestinal maturity to facilitate the breakdown of complex carbohydrates.” They add that since several pig pathogens (for example Salmonella typhimurium and Lawsonia intracellularis) mainly colonise the mucosa of the ileum, mucin production may be particularly useful as protective strategy against disease.

Overall, the scientists concluded that inclusion of BSFM in the diet positively influenced the microbiota at the start of the large intestine as well as small intestinal mucin dynamics of the piglets “in terms of selection of potentially-beneficial bacteria and preservation of mature mucin secretory architecture, without determining the development of gut inflammation. These findings further confirm the suitability of including insect meal in swine diets.”

The team calls for further research to confirm the findings of this study and to address some of the study limitations; both the gut sampling and the analysis methods may have caused the loss of most non-tissue mucins.