307 Use of defatted black soldier fly larvae meal (BSFLM) as an alternative and functional ingredient in canine nutrition

Abstract Black soldier fly (Hermetia illucens) larvae meal (BSFLM) is an alternative, sustainable, and nutrient-rich ingredient for pet foods. However, limited information is available on optimal inclusion levels and its functional properties. The objective of the study was to evaluate the effects of incremental levels of BSFLM (15% or 30%) as a partial or full substitute for chicken by-product meal (CM) in extruded diets. Three complete and balanced diets were formulated and extruded: Control, 15% BSFLM, and 30% BSFLM. The effects of the diets on nutrient digestibility, fecal metabolites and microbiota, and serum oxidative stress and inflammatory biomarkers in adult dogs were examined. A complete randomized design was used with adult Beagles (n = 10/treatment). The experimental period lasted 70 d, consisting of a 14-d adaptation to the control diet followed by 56-d test period. Data were analyzed using SAS Proc Mixed 9.4 with P ≤ 0.05 significance. All diets were well-accepted by the dogs; food intake and fecal output were not affected (P > 0.05) by treatment. Apparent total tract digestibility (ATTD) of dry matter, crude protein, and fat did not differ among treatments, whereas ATTD of organic matter (81.2%) and total dietary fiber (18.9%) was less (P < 0.05) for dogs fed 30% BSFLM in contrast with the Control group (83.2% and 30.3%, respectively). Fecal concentrations of total short-chain fatty acids and total phenols were less (P < 0.05) for dogs fed 30% BSFLM relative to dogs fed Control. No treatment effect was observed for serum biomarkers of oxidative stress and inflammation. Fecal microbial diversity differed between Control and 30% BSFLM groups. Overall, extruded diets containing 15% or 30% were well-digested by dogs as demonstrated by similar ATTD coefficients compared with Control. Intrinsic presence of chitin in BSFLM, and other insect-derived ingredients, can behave like insoluble dietary fiber in a food matrix, which would explain the decreased ATTD for organic matter and total dietary fiber, as well as less fecal concentration of total short-chain fatty acids. The inclusion of 30% BSFLM may have decreased protein hindgut fermentation due to less fecal concentration of total phenols. Altogether, the inclusion of 15% BSFLM resulted in similar physiological responses in comparison with dogs fed the Control diet. Greater inclusion levels of BSFLM may impact ATTD, however, it also has the potential to modulate fecal metabolites and microbiota, without negatively affecting fecal microbial richness.