Enriching Eggs Naturally: The Nutritional Power of Black Soldier Fly Whole Dry Larvae

The current investigation examined the effect of inclusion of Black soldier fly (Hermetia illucens; BSF) dry larvae in hens' diet on egg quality and hen performance. A total of 260 brown egg-laying hens (RIR × RIW) were divided into four groups (65 hens/group; 5 pens/group) and fed with control and experimental diets (inclusion rates 3%, 6%, 9%). Although the four-week feeding period did not influence production parameters, yolk color responded positively to the test diets, showing a linear increase with the percentage of BSF inclusion rate (p < 0.001). This was reaffirmed by the increased levels of yolk carotenoids (astaxanthin and β-carotene) and α-tocopherol, with notable differences in 6% and 9% BSF-fed groups (p ≤ 0.003). Lipids are an important factor in carotenoid absorption and assimilation, and the combination of fat content and carotenoids in BSF suggests the potential of this system for egg enrichment. Along with the increased antioxidant levels, a novel finding is the positive correlation between BSF inclusion rates and hens' egg yolk levels of C:15 and C:17 fatty acids, key players in the core mechanisms of cell health and longevity. Altogether, the results provide evidence of the potential of BSF for enrichment of eggs with carotenoids and vitamins with strong antioxidant activity, which would have a positive effect on human health.