This work investigated the impact of partially substituting soybean meal protein with defatted black soldier fly larvae (DBSFL) meal protein on performance parameters, carcass traits, meat chemical composition, cecal microflora, and economic efficiency in growing Muscovy ducks. Five dietary treatments were established, consisting of a basal control and four replacement levels in which DBSFL meal protein replaced SBM protein at 20%, 40%, 60%, and 80%. These treatments utilized 100 one-week-old ducklings, randomly distributed across four replicates of five birds each. The experimental duration was extended for 56 days. The 20% and 40% substitutions significantly improved performance parameters (p<0.05). Carcass traits and abdominal fat percentage also increased notably (p<0.05) in the DBSFL meal groups. The proximate composition of the meat showed no significant differences, except for crude protein, which increased significantly. The concentrations of meat cholesterol and triglycerides were significantly reduced (p<0.05) in the treated groups. The addition of DBSFL meal significantly (p<0.05) decreased harmful bacteria such as E. coli and Salmonella, while also notably (p<0.05) boosting beneficial bacteria in the ducks' cecum. The monetary value of the diets improved with the addition of the DBSFL meal. Substituting soybean meal protein with DBSFL meal protein, especially at 20%, enhances performance, meat nutritional quality, carcass traits, and gut microbiota, confirming DBSFL meal as a viable alternative protein supplement.

This study evaluated the effects of dietary lignan supplementation on the performance, antioxidant status, immune response, and meat composition of Japanese quails (Coturnix coturnix japonica). A total of 105 one-day-old unsexed Japanese quails were randomly assigned one of five treatment groups, each with 3 replicates of 7 chicks. The groups consisted of a control group that fed a basal diet (BD), an antibiotic group (0.05% bacitracin methylene salicylate in BD), and three lignan-supplemented groups (50, 100, and 150 mg lignans/kg diet, designated L50, L100, and L150, respectively). Dietary lignans had no significant effect on growth performance parameters, including body weight, weight gain, or feed conversion ratio. However, the L100 group exhibited significant reductions in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), creatinine, and uric acid (P<0.05) compared to other groups. Furthermore, lignan supplementation significantly lowered serum cholesterol and total lipids (P<0.05), without affecting triglycerides or glucose. In the L100 group, a significant increase in antioxidant markers, including glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and total superoxide dismutase (T-SOD), was observed, alongside a significant reduction in malondialdehyde (MDA) levels (P<0.05). Regarding inflammatory cytokines, both the L100 and L150 groups showed significantly reduced levels of interleukin-1 (IL-1β) and TNF (P<0.05), while lower levels of interleukin-6 (IL-6) and interleukin-12 (IL-12) were observed in Anti group followed by L100 group (P<0.05). Lower levels of triglyceride, cholesterol and malondialdehyde (TBARS) in meat were observed in L150 group (P<0.05). In conclusion, the addition of lignans in the diet of Japanese quails did not affect the quail performance, while level of 100 lignans mg/kg diet improved the biochemical, antioxidant system, and immune activities.