The oil extracted from black soldier fly (Hermetia illucens) larvae has recently emerged as a sustainable and innovative feed ingredient. Conventional fats are often included in the diets of dairy cows, but some of them are associated with negative environmental impact, such as those derived from oil palm cultivation. The aim of this study was to characterize the effects of replacing palm oil by black soldier fly oil on the lipid metabolism in the rumen of cows, which is a key aspect determining the digestion and subsequent utilization of lipids for milk fat production. Surprisingly, we observed a decrease in total fat content in the ruminal fluid of cows fed the black soldier fly oil, which was associated with an extensive disappearance of lauric acid (the most abundant fatty acid in the insect oil). The study of lipids that represent biomarkers of ruminal microbiota suggest possible changes in this microbial community, which may derive, at least in part, from the antimicrobial effect of lauric acid. Overall, our results suggest that H. illucens oil can be used in dairy cow diets without detrimental effects on ruminal lipid metabolism, as we observed only minimal changes in metabolic pathways compared to the use of palm oil, thus supporting its potential use as a sustainable feed ingredient.

Read the full article in the Journal of Animal Science.