发酵豆粕对低温环境下断奶犊牛生长性能和免疫反应的影响

Effects of fermented soybean meal on growth performance and immune response of weaned calves at low temperature environment

文章旨在研究日粮中不同浓度的发酵豆粕对低温环境断奶犊牛生长性能、血液参数和免疫反应的影响。试验选择平均体重为(39.5±3.3)kg的荷斯坦犊牛39头,随机分为3组,3种试验日粮分别在基础日粮中以0、8%和12%发酵豆粕替代豆粕,试验进行9周,试验牛在59 d时突然断奶,且在试验过程中一直进行圈养处理。结果显示:本试验所用的发酵豆粕粗蛋白质含量较高,瘤胃不可降解蛋白比例较高,小分子肽比例较高。日粮处理与周龄对犊牛平均日增重的影响具有显著交互作用(P<0.05),其中12%发酵豆粕组在试验第2周增重最少,但在第6周增重最多,之后8%发酵豆粕组增重最大。12%发酵豆粕组较其他组显著提高了犊牛的肩高和腰高(P<0.05)。在断奶后1和3 d,对照组犊牛的中性粒细胞、中性粒细胞与淋巴细胞比值和血糖浓度较高,但与12%发酵豆粕组相比,淋巴细胞的比例较低。断奶前2 d和断奶后3 d,8%发酵豆粕组白细胞计数表现最高,而对照组在此期间胰岛素水平显著提高(P<0.05)。综上所述,在试验条件下,日粮添加发酵豆粕提高了犊牛的生长性能,同时通过显著降低促炎介质的浓度降低了断奶应激。

The effects of different concentrations of fermented soybean meal on growth performance,blood parameters and immune response of weaned calves in low temperature were studied.Thirty-nine Holstein calves with an average weight of 39.5±3.3kg were selected and randomly divided into three groups.Soybean meal was replaced with 0,8%and 12%fermented soybean meal in the base diet for 9 weeks.All the calves were suddenly weaned at 59 d,but were kept alone in cages until the end of the experiment.The results showed that the content of crude protein in fermented soybean meal was higher,the proportion of non-degradable protein in rumen was higher,and the proportion of small molecular peptide was higher.There was a significant interaction between diet and week age on the average daily weight gain of calves(P<0.05),among which the 12%fermented soybean meal group gained the least weight in the second week of the experiment,but gained the most in the sixth week,and then gained the most in the 8%fermented soybean meal group.The 12%fermented soybean meal group significantly increased the shoulder height and waist height of calves compared with other groups(P<0.05).At 1 and 3 d after weaning,the neutrophils,neutrophils to lymphocyte ratio and blood glucose concentration of control calves were higher,but the percentage of lymphocyte was lower than that of the 12%fermented soybean meal group.At 2 d before and 3 d after weaning,the white blood cell count of 8%fermented soybean meal group was the highest,while insulin level in the control group was significantly increased during this period(P<0.05).In summary,the addition of fermented soybean meal to the diet improved the growth performance of calves under experimental conditions and reduced weaning stress by significantly reducing the concentration of pro-inflammatory mediators.