酵母培养物对断奶犊牛生长性能及瘤胃发酵的影响

Effect of yeast culture on growth performance and rumen fermentation of weaned calves

试验旨在研究断奶后犊牛日粮补充酵母培养物(YC)对犊牛采食、生长和瘤胃发酵的影响。将24头3月龄健康荷斯坦犊牛按体重和日龄随机分配至3个处理组,每组8头。对照组饲喂基础日粮,不添加YC(CON),2个处理组分别按日粮干物质1%(YC1)和2%(YC2)比例添加YC。试验期为60 d。结果显示,犊牛日粮添加YC显著增加了犊牛干物质采食量(DMI)和平均日增重(ADG)以及饲料效率(P<0.05);犊牛血液生化指标各处理间差异不显著(P>0.05),但YC处理显著增加了犊牛血浆中BHBA浓度(P<0.05);对于免疫指标IgG、IgA和IgM,各处理组间差异不显著(P>0.05);犊牛日粮添加YC处理对瘤胃pH值、瘤胃液中乙酸和丁酸含量没有显著影响(P>0.05),但显著增加了丙酸和总挥发酸浓度(P<0.05);对于消化酶活性,淀粉酶在不同处理组间差异不显著(P>0.05),但YC处理显著增加了羧甲基纤维素酶活性(P<0.05);此外,YC处理显著增加了瘤胃液中MCP浓度。结果表明,三月龄犊牛日粮补充酵母培养物增加了犊牛干物质采食量和平均日增重,提高了饲料效率,同时增加了瘤胃液中纤维素酶活性和挥发酸浓度,稳定了瘤胃内环境。综上所述,补充酵母培养物对断奶后犊牛生长和健康具有积极作用。

The study was to investigate the effect of yeast culture(YC)supplementation on the feeding,growth and rumen fermentation of weaned calves.24 three-month-old healthy Holstein calves were randomly assigned into three groups.Each treatment group was consisted of eight calves.The control group was fed with basic diet without YC(CON),and YC was added to treatment groups in the ratio of 1%(Y C 1)and 2%(YC2)of dry matter.The calves were free to diets and water for 60 d.The results showed that YC significantly increased the DMI,ADG and feed efficiency of calves(P<0.05).There was no significant difference among the treatments for blood biochemical indexes of calves(P>0.05),but YC significantly increased the concentration of BHBA in the plasma(P<0.05).For IgG,IgA and IgM,there was no significant difference among the treatment groups(P>0.05);YC supplementation significantly increased the concentration of BHBA in the plasma of calves(P<0.05).There was no significant effect on rumen pH value,acetic acid and butyric acid in rumen fluid(P>0.05),but the concentration of propionic acid and total volatile fatty acids increased significantly(P<0.05).For digestive enzyme activity,there was no significant difference among the three treatment groups(P>0.05),but YC treatment significantly increased carboxymethylcellulose activity(P<0.05).In addition,YC treatment significantly increased MCP concentration in rumen fluid.The results showed that supplementation with YC to three-month-old calves increased the dry matter intake and average daily gain of calves,increased feed efficiency,cellulase activity and volatile fatty acids concentration in rumen fluid,and stabilized rumen internal environment.Supplementation with YC has a positive effect on the growth and health of calves.