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

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.

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.

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.