不同断奶模式对仔猪免疫器官指数和免疫球蛋白含量的影响

Effects of weaning modes on immune organ indexes and immunoglobulin contents of piglets

【目的】研究不同断奶模式对仔猪免疫器官指数以及免疫球蛋白A(IgA)、IgG、IgM含量的影响。【方法】选用27窝“杜×长×大”仔猪,随机分为3个试验组,分别为常规断奶组(C组)、喷洒气味剂组(S组)和先混群后断奶组(M组),每组3个重复,每个重复3窝。C组仔猪28日龄进行常规断奶、混群;S组仔猪28日龄断奶、混群,同时每天向仔猪身上喷洒体积分数2%戊二醛溶液,持续喷洒7 d;M组仔猪21日龄原地混群,28日龄断奶。断奶后第8天称试验猪体质量,解剖采集扁桃体、脾脏、胸腺、下颌淋巴结、腹股淋巴结,称取其质量,计算免疫器官指数;刮取空肠和回肠黏膜,采集血液分离血清,ELISA方法测定肠黏膜和血清中IgA、IgG、IgM和白介素2(IL-2)的含量。【结果】与C组相比,S组免疫器官指数均提高,除脾脏和下颌淋巴结指数差异不显著(P>0.05)外,其他均差异显著(P<0.05);M组免疫器官指数均显著高于C组和S组(P<0.05)。S组回肠黏膜、M组空肠和回肠黏膜中IgA、IgG、IgM含量均较C组显著提高(P<0.05),S组空肠黏膜中IgA、IgG、IgM含量与C组无显著差异(P>0.05),M组空肠和回肠黏膜中IgM含量均较S组显著提高(P<0.05)。S组血清中IgA、IgM含量较C组显著提高(P<0.05),M组血清中IgA、IgM、IgG含量均较C组显著提高(P<0.05),M组IgG含量显著高于S组(P<0.05)。S组回肠黏膜中IL-2含量显著高于C组(P<0.05),M组肠黏膜和血清中IL-2含量均显著高于C组和S组(P<0.05)。【结论】在仔猪体表喷洒体积分数2%戊二醛溶液和先混群后断奶的断奶模式均能减轻仔猪断奶应激,提高免疫器官指数,增强机体免疫应答水平,其中先混群后断奶模式的效果更优。

【Objective】This study investigated the effects of weaning modes on indexes of immune organs and contents of immunoglobulin A(IgA),immunoglobulin G(IgG)and immunoglobulin M(IgM)of piglets.【Method】Twenty-seven litters of“Duroc×Landrace×Large White”piglets were randomly divided into three groups of conventional weaning group(Group C),odorant spraying group(Group S)and mixing before weaning group(Group M).Each group had 3 replications,and each replication had 3 litters.The piglets in Group C were weaned and mixed at the age of 28 days,and the piglets in Group S were weaned and mixed at the age of 28 days.At the same time,glutaraldehyde solution at volume fraction of 2%was sprayed on piglets in Group S every day for 7 days.The piglets in Group M were mixed in situ at the age of 21 days and weaned at the age of 28 days.Seven days after weaning,body mass of pigs was weighed.Tonsils,spleen,thymus,mandibular lymph nodes and inguinal lymph nodes were collected and weighed respectively,and immune organ index was calculated.The mucosa of ileum and jejunum were scraped,and serum was collected and prepared.The contents of immunoglobulin A(IgA),immunoglobulin G(IgG),immunoglobulin M(IgM)and interleukin-2(IL-2)in intestinal mucosa and serum were detected by ELISA assay.【Result】Compared with Group C,the immune organ indexes of Group S increased,and all increases were significant(P<0.05)except spleen and mandibular lymph node indexes(P>0.05).The immune organ indexes of Group M were significantly higher than those of Group C and Group S(P<0.05).Compared with Group C,IgA,IgG and IgM contents in ileum mucosa of Group S as well as ileum mucosa and jejunum mucosa of Group M were significantly increased(P<0.05),but there were no significant differences among IgA,IgG and IgM contents in jejunum mucosa among Group S and Group C(P>0.05).IgM content in jejunum and ileum mucosa in Group M was significantly increased compared with Group S(P<0.05).IgA and IgM contents in serum of Group S were significantly increased compared with Group C(P<0.05),and IgA,IgM and IgG contents in serum of Group M were significantly increased compared with Group C(P<0.05),while there was significant difference in IgG content between Group M and Group S(P<0.05).The IL-2 content in ileum mucosa of Group S was significantly higher than that of Group C(P<0.05),and IL-2 content in intestinal mucosa and serum of Group M was significantly higher than that of Group C and Group S(P<0.05).【Conclusion】Spraying glutaraldehyde solution at volume fraction of 2%on surface of piglets and mixing in situ before weaning mode could reduce weaning stress,improve immune organ index and enhance immune response level of piglets.The mode of mixing in situ before weaning was the best.