Effect of Periplaneta americana Residue Feed on Immunity, Antioxidant Capacity, and Transcriptome in Chickens: A Study on Sanhuang Chickens

This study investigated the effects of Periplaneta americana residue (PAR) on the immune function, antioxidant capacity, and transcriptome of Sanhuang chickens. Six hundred 30-day-old Sanhuang chickens were divided into six groups with diets of varying PAR replacement of soybean meal from 0 to 100% in increments of 20%. Samples were taken on day 100. The results indicated that PAR did not significantly affect growth performance (p > 0.05). PAR significantly elevated the levels of IL-1β, IL-2, TNF-α, IgA, IgG, and IgM in both the serum and spleen (p < 0.05). Moreover, it markedly increased the GSH-Px, T-AOC, SOD, and CAT levels in the serum and liver (p < 0.05) and reached optimal levels of immune factors and antioxidant indicators at diet 2. Transcriptomic analysis revealed that substituting PAR for soybean meal downregulated genes associated with immune diseases and infectious disease pathways. Substituting soybean meal with PAR enhanced the resistance of Sanhuang chickens to pathogenic factors and oxidative stress, with no impact on growth performance. The optimal improvement was observed with diet 2.