【摘要】 为了探讨溶菌酶对围产期(产前第21天到产后第21天,表示为-21st~21st d,下同)奶牛免疫抑制的缓解作用及其相关机制,选择18头围产期奶牛,分为3组,每组6头,Ⅰ组:每头奶牛每日饲喂基础日粮+2g溶菌酶,Ⅱ组:每头奶牛每日饲喂基础日粮+4g溶菌酶,Ⅲ组作为对照组,只饲喂基础日粮,试验期为45d。应用ELISA双抗体夹心法检测试验牛血清中C3、C4及IFN-γ、TNF-α、IL-6的质量浓度。结果显示,Ⅰ、Ⅱ组奶牛在-10th~7th d阶段,血清中C3、C4的质量浓度明显高于对照组(P<0.05)。Ⅱ组血清中IFN-γ、TNF-α和IL-6的质量浓度均低于对照组,即IL-6的质量浓度从-14th到21st d与对照组存在极显著差异(P<0.01),TNF-α的质量浓度从0到21st d与对照组差异均极显著(P<0.01),IFN-γ的质量浓度虽然与对照组差异不显著(P>0.05),但其含量也明显低于对照组;而Ⅰ组IFN-γ、TNF-α和IL-6的质量浓度与对照组均差异不显著(P>0.05)。结果表明,溶菌酶对围产期奶牛的免疫抑制有缓解作用,且Ⅱ组的缓解作用明显优于Ⅰ组,这可能与溶菌酶能增加血清中C3、C4的质量浓度和降低IFN-γ、TNF-α和IL-6的质量浓度有关。更多还原

【Abstract】 In order to assess the effects of lysozyme on immune injury of the transition cows,and to analyze the mechanism of impared immune function in perpartum period,18perinatal cows were divided into three groups(6cows per group).The 2g and 4g lysozyme were added to each perinatal cow basal diets of GroupⅠand GroupⅡ,respectively,and GroupⅢis a control group.A trial period was 45d.The contents of complement 3(C3),complement 4(C4),interferon-γ(IFN-γ),tumour necrosis factor-α(TNF-α),and interleukin-6(IL-6)in serum were detected by double-antibody sandwich ELISA.In result,during the period of-10th d to 7th d,the contents of C3and C4in serum in GroupⅠand GroupⅡ were significantly higher than that in the control group(P<0.05).The contents of IFN-γ,TNF-α,and IL-6in serum in GroupⅡ were lower than that in the control group.Compared with the control group,from-14th d to 21st d,IL-6 content was significantly different(P<0.01),and the content of TNF-αfrom 0dto 21st d was significantly different too.The content of IFN-γhad no significantly different from that in the control group(P>0.05), but its content was lower than that in the control group.However,the contents of IFN-γ,TNF-α,and IL-6 in serum in GroupⅠ were not significantly different(P>0.05)from that in the control group.The results showed that lysozyme might play a crucial role in an immunosuppressive state.Besides,in terms of immunosuppression,the relieve effect of feeding 4g lysozyme per transition cow per day was obviously more superior than that of GroupⅠfed with 2g lysozyme.The effect of lysozyme for transition cow might be associated with the increasing of the C3and C4contents in serum and down-regulation of the cytokines IFN-γ, TNF-αand IL-6.更多还原