Effects of BSFL on growing-finishing pigs in growth performance, nutrient digestibility, blood profiles, and gas emission

This study was conducted to analyze the effects of replacing fishmeal in the diet of growing-finishing pigs with black soldier fly larvae (<italic>Hermetia illucens</italic> L., BSFL) on growth performance, nutrient digestibility, blood profiles, and gas emissions, and to determine whether BSFL can be effectively applied as an alternative protein source. A total of 36 10-week-old crossbred growing pigs [(Landrace × Yorkshire) × Duroc] with initial body weight (BW) 34.82 ± 0.43 kg were used in this study. Each treatment had 6 replicate pens, and 2 pigs were assigned to each pen. The three treatments were as follows: a basal diet containing 1% fishmeal (FM); a basal diet without fishmeal and included with 1% BSFL powder (BSFL1); a basal diet without fishmeal and included with 2% BSFL powder (BSFL2). There were no significant differences among treatment groups in BW, average daily gain, average daily feed intake, and feed efficiency during the entire experimental period. The BSFL2 group in weeks 6 and 9 showed significantly higher (<italic>p</italic> &lt; 0.05) crude protein (CP) digestibility than the FM group. In all indispensable amino acids except arginine, the BSFL1 and BSFL2 groups showed significantly higher (<italic>p</italic> &lt; 0.05) digestibility than the FM group at week 6. The BSFL2 group showed significantly higher (<italic>p</italic> &lt; 0.05) digestibility of threonine, valine, isoleucine, leucine, lysine, arginine, and methionine than the BSFL1 group. In the dispensable amino acids, the BSFL2 group showed significantly higher (<italic>p</italic> &lt; 0.05) digestibility of proline, glycine, alanine, tyrosine, and cystine than the FM and BSFL1 groups. In all indispensable amino acids, the BSFL1 and BSFL2 groups showed significantly higher (<italic>p</italic> &lt; 0.05) digestibility than the FM group at week 9. There were no significant differences among treatment groups in blood profiles and gas emissions during the entire experimental period. Therefore, it is thought that BSFL can be used to replace fishmeal in diets for growing-finishing pigs, and when 2% of BSFL is included, it is thought to be an appropriate amount to include in diets for growing-finishing pigs, as it has the effect of improving the digestibility of CP and amino acids.