Ileal digestibility of amino acids in defatted black soldier fly larva meal and adult black soldier fly fed to pigs

Abstract

The objective was to determine crude protein (CP) and amino acids (AA) digestibility of fish meal, defatted black soldier fly (BSF;Hermetia illucens) larva meal, and adult BSF fed to pigs. Eight castrated male pigs with a body weight of 72.6 kg (standard deviation = 10.4) surgically fitted with T-cannulas in the distal ileum were individually housed in pens that were equipped with a feeder and a nipple drinker. The pigs were allotted to a replicated 4×5 incomplete Latin square design with 4 diets and 5 periods to obtain 9 replicates. Three experimental diets were prepared to contain fish meal (686 g/kg CP and 75 g/kg ether extract), defatted BSF larva meal (595 g/kg CP and 76 g/kg ether extract), and adult BSF (590 g/kg CP and 268 g/kg ether extract) as the sole source of AA. Additionally, a nitrogen-free diet based on corn starch and sucrose was formulated to determine the basal endogenous losses of CP and AA. All diets contained 5 g/kg chromium oxide as an indigestible marker. Each period consisted of 4 days of adaptation and 2 days of ileal digesta collection. The coefficient of standardised ileal digestibility (CSID) of CP in defatted BSF larva meal was lower (0.738 vs 0.883;P<0.05) than that in fish meal but was higher (P<0.05) than that in adult BSF (0.561). The CSID of all indispensable AA except for methionine and phenylalanine in defatted BSF larva meal was lower (P<0.05) than that in fish meal. The CSID of all AA except for proline in defatted BSF larva meal was higher (P<0.05) than that in adult BSF. Overall, AA in defatted BSF larva meal were less digestible than those in fish meal when fed to growing pigs but were more digestible than those in adult BSF.