Effects of Yeast Peptides on Growth Performance of Meat Rabbits,and Serum Cytokines and Liver Antioxidant Capacity of Lipopolysaccharide-Stressed Meat Rabbits
The purpose of this study was to investigate the effects of yeast peptide on the growth performance of meat rabbits and serum cytokines and liver antioxidant capacity of lipopolysaccharide-stressed meat rabbits.The trial was divided into two phases.Phase 1:a total of 160 healthy 35-day-old weaned Hyla line rabbits were selected with an initial body weight of(0.96±0.06)kg,and randomly divided into 4 groups(half male and half female),with 8 replicates per group and 5 rabbits per replicate.Rabbits in control group(CON group)and lipopolysaccharide group(LPS group)fed a basal diet,and those in yeast peptide group(YP group)and yeast peptide remission group(L-YP group)fed the basal diet supplemented with 100 mg/kg yeast peptide.The feeding experiment lasted for 35 days,including 7 days of pre-trial period and 28 days of experimental pe-riod.Data such as body weight and feed intake were recorded and growth performance indexes of meat rabbits during the phase 1 were calculated.Phase 2:at the end of phase 1,rabbits in the LPS group and L-YP group were intramuscularily injected with 200 μg/kg BW LPS,and rabbits in the CON group and YP group were in-jected with the same amount of normal saline.The samples were collected 4 h after injection with LPS or nor-mal saline,and serum cytokine content,liver antioxidant indexes and mRNA relative expression levels of an-tioxidant genes were measured.The results showed as follows:1)adding yeast peptide significantly increased the average daily gain and significantly decreased the feed to gain ratio of meat rabbits(P＜0.05),but had no significant effects on the average daily feed intake,diarrhea rate and mortality rate(P＞0.05).2)The contents of serum interleukin-6(IL-6),interleukin-8(IL-8)and reactive oxygen species(ROS)were significantly de-creased by adding yeast peptide(P＜0.05);lipopolysaccharide stress significantly increased the contents of ser-um tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,IL-8,transforming growth factor-β(TGF-β)and ROS of meat rabbits(P＜0.05);serum TNF-α,IL-6,IL-10 and TGF-β contents had signifi-cant interactions between yeast peptide and lipopolysaccharide(P＜0.05).Under lipopolysaccharide stress,adding yeast peptide significantly decreased the serum TNF-α and IL-6 contents of lipopolysaccharide-stressed meat rabbits(P＜0.05).3)Adding yeast peptide significantly increased the liver superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)activities and total antioxidant capacity(T-AOC)of meat rabbits(P＜0.05),and significantly decreased the liver malondialdehyde(MDA)content(P＜0.05);lipopolysac-charide stress significantly decreased the liver T-AOC and GSH-Px activity(P＜0.05);SOD activity and SOD mRNA relative expression level in liver had a significant interaction between yeast peptide and lipopolysaccha-ride(P＜0.05).Under lipopolysaccharide stress,adding yeast peptide significantly increased the liver SOD ac-tivity and SOD mRNA relative expression level of lipopolysaccharide-stressed meat rabbits(P＜0.05).In sum-mary,adding 100 mg/kg yeast peptide to the diet can improve the growth performance of meat rabbits,and ef-fectively relieve the immune stress response of meat rabbits induced by lipopolysaccharide by reducing the level of inflammation and improving the antioxidant capacity.[Chinese Journal of Animal Nutrition,2024,36(8):5308-5318]
万方数据
维普
