Regression method-derived digestible and metabolizable energy concentrations of partially defatted black soldier fly larvae meal for broiler chickens and pigs

Abstract

The energy value of partially defatted black soldier fly larvae meal (pBSFLM) was determined in 2 experiments with broiler chickens and growing pigs. Experiment (Exp.) 1 was conducted to evaluate the ileal digestible energy (IDE), metabolizable energy (ME), and nitrogen-corrected ME (MEn) of pBSFLM with broiler chickens, and Exp. 2 was conducted to evaluate the digestible energy (DE) and ME of pBSFLM in growing pigs. The index method using titanium dioxide was used in Exp. 1 whereas, the total collection method was used in Exp. 2, the pig study. Three experimental diets were prepared in each of the 2 studies: a corn-soybean meal basal diet (BD) and 2 test diets containing pBSFLM at either 100 or 200 g/kg to replace the energy-contributing ingredients in the BD. Eight replicate cages of broiler chickens at 16-d-old (6 birds per cage) in Exp. 1 or 8 barrows with a mean body weight of 20 kg in Exp. 2 were assigned to each diet. A linear increase (P < 0.05) was observed in the IDE concentration of the experimental diets in Exp. 1. With increasing dietary pBSFLM, linear and quadratic increases (P < 0.05) were observed in the MEn and ME concentrations in the diets, respectively. The inclusion of pBSFLM increased ME from 13.4 to 14.5 MJ/kg DM for 0 to 200 g/kg replacement of BD. When fed to broiler chickens, the regression-derived IDE, ME, and MEn concentrations in pBSFLM were 18.9, 19.8, and 17.7 MJ/kg DM, respectively. In Exp. 2, there was a linear decrease in DM digestibility and a linear increase in dietary DE concentration (P < 0.05) of experimental diets with increasing substitution of BD with pBSFLM. The metabolizability of dietary gross energy linearly decreased (P < 0.05) but the ME concentration quadratically increased (P < 0.05) as the replacement of BD with pBSFLM in the experimental diet increased from 0 to 200 g/kg. In pigs, the regression-derived DE and ME estimates were 21.0 and 19.7 MJ/kg, respectively. The results from this study showed that pBSFLM is a potential feed ingredient for inclusion in the diet formulation for broiler chickens and pigs.