Effect of Replacement Dietary of Animal Protein with Insect Meal (Hermetia illucens) on Growth Performance, Nutrient Digestibility, Blood Profile, Gas Emission, and Fecal Microbial in Weaned Pigs

This study was conducted to investigate the effects of defatted and hydrolyzed forms of black soldier fly (Hermetia illucens; HI) larvae as fishmeal substitutes in the diet of weaned pigs on growth performance, nutrient digestibility, blood profile, gas emission, and fecal microbial. The 48 4-week-old weaned pigs [(Landrace × Yorkshire) × Duroc] with an initial body weight (BW) of 9.39 ± 1.02 kg were randomly assigned to a completely randomized three dietary treatments. Each treatment had 4 replicate pens, and 3 pigs were assigned to each pen. The three treatments were as follows: 1) a basal diet (CON), 2) a basal diet without a fish meal and substitute with defatted HI powder (T1), and 3) a basal diet without a fish meal and substitute with hydrolyzed HI powder (T2). The experiments progressed in 6 weeks. There were no significant differences (P > 0.05) among the treatment groups in BW, average daily gain, average daily feed intake, and feed efficiency during the entire experimental period (Table 1). At 2 wk, the CON and T1 groups increased (P < 0.05) crude protein (CP) digestibility compared with the T2 group (Table 2). The CON group had greater (P < 0.05) CP digestibility than the T2 group at 6 wk. At 6 wk, the T1 group showed a tendency for greater gross energy (P = 0.095) than the T2 group. The T1 group had greater (P < 0.05) lysine digestibility than the CON group at 2 wk (Table 3). Also, The T1 and T2 groups showed a tendency for greater (P = 0.070) glutamic acid digestibility than the CON group. At 6 wk, the T2 group increased (P < 0.05) lysine, arginine, and methionine digestibility compared with the CON group (Table 4). There were no significant differences (P > 0.05) among the treatment groups in blood profile and gas emission (Table 5 and 6). The T2 group had significantly greater (P < 0.05) lactobacillus counts than the T1 group at 4 wk (Table 7). In conclusion, it was found that the defatted and hydrolyzed forms of HI as a substitute for a fish meal did not negatively affect growth performance, blood profiles, and gas emissions. Also, the defatted and hydrolyzed forms of HI could improve nutrient digestibility and lactobacillus counts, which are beneficial bacteria in the intestine. Therefore, it is considered that the diets of weaned pig containing defatted or hydrolyzed HI has sufficient potential to replace fishmeal, which is an existing animal protein source in the diet.