复合多肽制剂对肉鸡免疫功能的影响

Effects of Compound Polypeptide on the Immune Function in Broilers

旨在探索复合多肽制剂对于肉鸡免疫功能的影响。选取1日龄肉鸡120羽,随机分为4组(每组3个重复),于6日龄和13日龄,分别采用喷雾的方式添加0.05 mL/只(低剂量)、0.1 mL/只(中剂量)、0.15 mL/只(高剂量)的复合多肽制剂,空白对照采用生理盐水喷雾。于7、14、21、28、35、42日龄用HA/HI方法检测肉鸡新城疫病毒(NDV)抗体滴度。21、42日龄测定肉鸡免疫器官指数。采用ELISA测定7、14、21日龄肉鸡血清中细胞因子含量。复合多肽制剂能显著提高肉鸡新城疫病毒抗体水平(P<0.05),其中14日龄低剂量组和21、28日龄低剂量组和中剂量组新城疫病毒抗体滴度显著升高(P<0.05),但其对肉鸡免疫器官指数无显著影响(P>0.05)。复合多肽制剂能影响肉鸡血清细胞因子的表达水平,7日龄各试验组肉鸡血清中IL-4含量显著升高且与给药剂量正相关(P<0.05),7、14日龄试验鸡血清中IL-6含量显著降低(P<0.05),14、21日龄各剂量组IL-10含量显著下降(P<0.01)。结果表明,复合多肽制剂对肉鸡的免疫功能均具有一定的调节作用,低剂量复合多肽制剂上调新城疫病毒抗体水平效果最好。

This study was conducted to investigate the effects of compound polypeptide on immune function of broilers.A total of 120 one-day-old broilers were randomly divided into 4 groups with 3 replicates per group.At 6 and 13 days,low dose,middle dose and high dose were added with 0.05,0.1 and 0.15 mL compound polypeptide per broiler,respectively.Blank control was sprayed with saline solution.Antibody titers of Newcastle disease virus(NDV)were detected at 7,14,21,28,35 and 42 d.Broiler immune organ indexes were measured at 21 and 42 d.The contents of cytokines in serum of broilers aged 7,14 and 21 d were determined by ELISA.The results showed that indoor spraying compound polypeptide could significantly increase the level of NDV antibody in broilers,and the titers of NDV antibody in low-dose group at 14 d and that in low-dose and middle-dose group at 21 and 28 d were significantly higher than that in control group,but had no effect on immune organ indexes.Compound polypeptide could affect the expression of cytokines in serum of broilers,among which,IL-4 in the serum of broilers in experimental groups was significantly increased at 7 d compared with control group in a dose-dependent manner,and the concent of IL-6 was significantly decreased at 7 and 14 d compared with control group.IL-10 contents in each dose group at 14 and 21 d were significantly decreased.These results showed that the indoor spraying compound peptide had effect on immune function of broilers,and low-dose compound peptide had the most obvious effect on the level of NDV antibody.