Effects of cage layer on growth performance,slaughter performance,serum biochemical indexes,antioxidant capacity,and immune function of yellow-feathered broilers

WANG Fang; FENG Jiaqi; ZHU Zhenxin; NAN Shanshan; PANG Xiaotong; ZHANG Fei; NIE Cunxi

doi:10.13557/j.cnki.issn1002-2813.2025.02.010

Abstract：The study aimed to investigate the effects of cage layer on the growth performance,slaughter performance,serum biochemical indexes,antioxidant capacity,and immune function of yellow-feathered broilers.A total of 480 one-day-old fast-growing male yellow-feathered broilers were randomly divided into three groups,with eight replicates per group and 20 broilers per replicate.A three-tier cage rearing system was used,with the lower-layer group(L group),middle-layer group(M group),and upper-layer group(U group).The experimental period lasted for 63 days.The results showed that there were no significant differences in final weight,average daily weight gain,average daily feed intake,and feed-to-weight ratio among the L,M,and U groups at each stage(P＞0.05).The leg muscle percentage in the M and U groups was significantly higher than that in the L group(P＜0.05).Compared with the M group,the thymus index was significantly lower in the L group(P＜0.05),and the bursa of Fabricius index was significantly lower in the U group(P＜0.05).The serum alanine aminotransferase(ALT)activity was significantly higher in the L group(P＜0.05).Compared with the L group,the serum total cholesterol(TC)content was significantly lower in the M and U groups(P＜0.05),while serum urea nitrogen(BUN)was significantly higher(P＜0.05).The total antioxidant capacity(T-AOC)of serum was significantly lower in the L and U groups than in the M group(P＜0.05),and the serum malondialdehyde(MDA)content was significantly lower in the L and M groups than in the U group(P＜0.05).Compared with the L group,the relative expression levels of interleukin-4(IL-4)and interleukin-10(IL-10)were significantly upregulated in the M group(P＜0.05),while they were significantly downregulated in the U group(P＜0.05).The study indicates that under the three-tier cage rearing conditions,the cage layer had certain effects on the slaughter performance,serum biochemical indexes,antioxidant capacity,and immune function of yellow-feathered broilers.The intestinal immune function was affected by regulating the expression level of intestinal immune-related genes,and the antioxidant oxidation and immune function of middle-layer yellow-feathered broilers were the best.