热应激牛初乳对新生犊牛血清免疫指标的影响研究

Effect of the heat stress bovine colostrums on immune index in newboth calves serum

新生犊牛通过初乳获得被动免疫,但是关于热应激对新生犊牛被动免疫的影响程度尚不清楚。本试验旨在研究热应激牛初乳对新生犊牛被动免疫是否有显著影响,并与非热应激生产条件下进行比较。试验动物为对应于采食热应激和非热应激母牛初乳的新生犊牛各4头,在其采食母牛初乳后的不同时间内采血用于免疫指标分析。结果表明:热应激奶牛哺乳犊牛血清中各成分含量在144h内均低于非热应激奶牛哺乳犊牛血清中相对应成分,其中IgG、T3、T(472h内)变化差异显著(P<0.05),INS和IGF-Ⅰ变化差异不显著(P>0.05),热应激在一定程度上影响新生犊牛被动免疫,有关机理有待于进一步研究。

The passive immunization of newboth calves was obtained by colostrums, but the influencing degree of the effect the heat stress on passive immunization of newboth calves is dimness. The main object is study the effect the heat stress on passive immunization of newboth calves, and compare with the unheated stress. The 4 newboth calves that eat the colostrums in the heat stress and unheated stress were selected, and the immune components in different time in 4 newboth calves serum were analyzed. The results are as follows： the content of the immune components in 144 h in calves serum in heat stress are lower that in unheated stress, the difference of IgG, T3, T4 was significant（P〈0.05）, but the different of INS, IGF-Ⅰ were not significant（P〉0.0 5）. The conclusion is： compared with the unheated stress, the content of IgG, T3, T4, INS and IGF-Ⅰ in calves serum in heat stress is reduced（P〈0.05）, the difference of IgG, T3,T4 was significant（P〈0.05）, but INS and IGF-Ⅰ were not significant（P〉0.05）. The passive immunization of newboth calves is affected by the heat stress; but the mechanism will be studied further.