Apparent metabolizable energy of black soldier fly larval meal and its effects on nutrient utilization in broiler diets.

BACKGROUND: Black soldier fly larvae (BSFL) are a promising alternative protein source for use in animal feeds. This study aimed to measure the apparent metabolizable energy (AME) and nitrogen-corrected apparent metabolizable energy (AMEn) of defatted (161 g kg-1 ether extract) and full-fat (438 g kg-1 ether extract) BSFL, and evaluated the effects of their dietary inclusion on nutrient utilization in broilers. RESULTS: A total of 108 28-day-old Shengze 901 male broilers were randomly assigned to the control group (CON; basal diet), the defatted BSFL group (DF; defatted BSFL replacing 150 g kg⁻¹ of the basal diet), and the full-fat BSFL group (FF; full-fat BSFL replacing 150 g kg⁻¹ of the basal diet), with 6 cages of 6 birds each. The AME and AMEn (dry matter basis) of defatted BSFL were 9.11 and 8.58 MJ kg-1, whereas those of full-fat BSFL were 18.93 and 17.43 MJ kg-1, respectively. Both BSFL diets increased crude fiber digestibility and decreased ash digestibility (P < 0.05). The DF group had lower dry matter, crude protein, and gross energy digestibility than FF and CON groups (P < 0.05), and the FF group had higher crude protein digestibility than both other groups (P < 0.05). The DF group exhibited higher nitrogen excretion, lower nitrogen retention, and elevated uric acid, whereas the FF group showed the opposite. CONCLUSION: This study determined the AME and AMEn of defatted and full-fat BSFL. The FF group showed higher nitrogen utilization, highlighting the advantage of full-fat BSFL as a protein and energy source for broilers, whereas the higher nitrogen excretion of the DF group suggests cautious inclusion of defatted BSFL. © 2026 Society of Chemical Industry.