Effect Of Active Peptide CC34 Yeast Culture On Amino Acid Transport Metabolism,Intestinal Development And Antioxidant Capacity In Lambs

To investigate the effects of active peptide CC34 yeast culture on amino acid transport metabolism,intestinal barrier function and antioxidant capacity of lambs.The lambs used in this experiment were divided into three groups according to the principle of one-way complete experimental design,in which 24 male lambs of 24 days of age(small-tailed cold sheep ×northeast fine hair sheep)were divided into three groups,in which the control group(CON)was the normal basal diet without any addition,the yeast culture group was the addition of yeast engineered bacteria without active peptide CC34 in the basal diet,and the active peptide CC34 yeast culture group was the addition of yeast engineered bacteria with active peptide CC34 in the basal diet.The yeast culture group is a base diet supplemented with yeast engineered to contain the active peptide CC34.Three lambs were randomly selected for intestinal and skeletal muscle tissue sampling on day 14 and day 28 of the test period,respectively,with a pre-feeding period of 8 days.Through the determination of amino acid transport carriers in duodenum and skeletal muscle,duodenal barrier function and antioxidant indexes in duodenum and skeletal muscle of lambs,the aim to investigate whether the active peptide CC34 yeast culture could alleviate the effect of weaning stress in lambs and provide some theoretical basis for the development of new feed additives in animal husbandry.The results of the study were as follows.(1)Effect of active peptide CC34 yeast culture on amino acid transport metabolism in the intestine and skeletal muscle of lambs:During the test period,both active peptide CC34 yeast culture group and yeast culture group showed no significant difference on duodenal alkaline amino acid transport carrier SLC3A2 and skeletal muscle acidic amino acid transport carrier AGC1 compared to CON(P>0.05).At day 14 of the test,the active peptide CC34 yeast culture group showed a significant increase(P<0.05)on the duodenal neutral amino acid transporter SLC7A5 and the basic amino acid transporter SLC7A9,but a significant decrease(P<0.05)on the skeletal muscle neutral amino acid transporter LAT1 compared to CON.At day 28 of the experiment,the active peptide CC34 yeast culture group showed a significant increase(P<0.05)on the lamb duodenal neutral amino acid transporter SLC3A1,but a significant decrease(P<0.05)on the skeletal muscle neutral amino acid transporter LAT1 compared to CON.(2)Effect of active peptide CC34 yeast culture on intestinal barrier function in lambs:During the test period,compared with CON,the active peptide CC34 yeast culture group showed a significant reduction in duodenal DLA and DAO in lambs(P<0.05)and was able to increase the expression levels of duodenal tight junction protein ZO-1,Claudin-1 and Occludin genes(P<0.05),decreased the gene expression level of duodenal host defense peptide SMAP-29(P<0.05),also increased the gene expression level of duodenal immune gene TLR-2(P<0.05),decreased the gene expression level of TLR-4(P<0.05),and also decreased the gene expression levels of duodenal cytokines IL-6,IL-10,and TNF-α(P<0.05).(3)Effect of active peptide CC34 yeast culture on the antioxidant capacity of lamb intestine and skeletal muscle:during the experimental period,the active peptide CC34 yeast culture group had a significant increase(P<0.05)on the duodenal T-AOC content,SOD content and GSH-Px content and decreased MDA content(P<0.05)in lambs compared to CON;compared to day 14,the active peptide CC34 yeast culture group significantly increased(P<0.05)the duodenal T-AOC content,SOD content and CAT content and decreased(P<0.05)the MDA content in lambs.During the test period,the active peptide CC34 yeast culture group significantly increased(P<0.05)and decreased(P<0.05)the MDA content of skeletal muscle T-AOC content and SOD content of lambs compared to CON;compared to day 14,the active peptide CC34 yeast culture group significantly increased(P<0.05)and decreased(P<0.05)the MDA content of skeletal muscle T-AOC content and SOD content of lambs.reduced MDA content(P<0.05).In conclusion,the active peptide CC34 yeast culture can improve the abnormal amino acid transport metabolism,enhance the intestinal barrier function and improve the antioxidant capacity of the body in lambs.