酪啡肽及其酪蛋白水解肽对早期断奶仔猪分泌型免疫球蛋白A和细胞因子水平的影响

Effects of β-Casomorphin-7 or Casein Peptides on Cytokines and Secretory-Immunoglobulinal A in 21 days’ Weaning Piglets

本文旨在研究酪啡肽及其酪蛋白水解肽对早期断奶仔猪分泌型免疫球蛋白A(SIgA)和细胞因子水平的影响。24头仔公猪随机分为对照组(正常哺乳28d断奶)、试验Ⅰ组(添加β-酪啡肽-7)和试验Ⅱ组(添加酪蛋白酶解物)。试验组于21d断奶,再连续添加酪蛋白胃蛋白酶解液或β-酪啡肽-710d,每天2次(共20mL),至32d,3组动物各随机取6头同时剖杀,取血、胃食糜和空肠食糜。观察其血清IL-2、TNF-α和胃肠内容物中SIgA的含量变化。结果表明:添加酪蛋白水解液组仔猪血清中IL-2的水平比对照组高75.9%,差异极显著(P<0.01);试验Ⅰ组血清中IL-2水平比对照组高35.7%,差异显著(P<0.05)。血清中TNF-α水平试验组略低于对照组。在对照组、试验Ⅰ和Ⅱ组仔猪的空肠食糜中均检测到SIgA,平均含量分别为(6.48±0.85)ng/g、(6.30±0.85)ng/g和(8.71±0.54)ng/g。与对照组相比,试验Ⅱ组差异极显著(P<0.05);胃食糜中未检测到SIgA。提示乳源活性肽对早期断奶仔猪细胞免疫和黏膜免疫活性具有一定的促进作用。

Twenty-four healthy male-piglets were randomly divided into two experimental groups （β-CM-7 group and casein hydrolysate peptides group） and a control group （given normal milk）. The piglets of experiment groups, weaning in 21 days, were successively fed with casein hydrolysate peptides or β-CM-7（2 times every day, 10 mL every time）. After 10 days,six piglets randomly selected from every group were killed and collected their serum and stomach and jejunum digesta. SIgA in stomach and jejunum digesta as well as IL-2 and TNF-α in serum were detected by radioimmunoassay. The results showed the level of IL-2 in serum was increased in experiment group Ⅰ and Ⅱ. Compared with the control, casein hydrolysate peptides group was more than 75% and rose significantly （P〈0.01）. β-CM-7 group was more than 40.7% （（P〈0.05）. There was a little lower in serum TNF-α of two Experiment groups than that of the control. SIgA can be detected from jejunum digesta of three groups. Their average concentration were （6.48 ± 0.32） ng/g jejunum digesta （Control group）, （6.30 ± 0.85）ng/g jejunum digesta （β-CM-7 group） and （8.71±0.54）ng/g jejunum digesta （casein hydrolysate peptides group）, respectively. Casein hydrolysate peptides group rose significantly （P〈0.05） compared with the control. We can not find SIgA in stomach digesta for all three groups. This experiment demonstrated that feeding the β-CMs to the weaning piglets could enhance their mucosal and cellular immunity.