冷季补饲矿物质盐砖对放牧牦牛犊牛体增重、瘤胃发酵和血清矿物元素含量的影响

Effects of Mineral Salt Brick Supplement on Body Weight Gain,Rumen Fermentation and Serum Mineral Element Contents of Grazing Yak Calves in Cold Season

本试验旨在研究冷季补饲矿物质盐砖对放牧牦牛犊牛体增重、瘤胃发酵和血清矿物元素含量的影响。试验选取健康、体重相近的4月龄牦牛犊牛28头,随机分成2组,每组14头(公母各7头)。对照组牦牛犊牛只进行放牧,试验组牦牛犊牛归牧后补饲矿物质盐砖。预试期7 d,正试期90 d。结果表明:试验组牦牛犊牛总增重和平均日增重显著高于对照组(P<0.05);试验组牦牛犊牛瘤胃液氨态氮(第30天、第60天、第90天)、乙酸(第30天、第60天、第90天)、丙酸(第60天、第90天)和总挥发性脂肪酸含量(第60天、第90天)显著高于对照组(P<0.05);试验组血清中磷、铁、铜、锌、锰、钴的含量与对照组相比有不同程度的提高。上述结果表明冷季补饲矿物质盐砖能促进放牧牦牛犊牛的生长,改善瘤胃的发酵功能,提高血清中磷、铁、铜、锌、锰、钴的含量。

This experiment was conducted to study the effects of mineral salt brick supplement on body weight gain,rumen fermentation and serum mineral element contents of grazing yak calves in cold season.Twenty-eight healthy 4-month-old yak calves with similar body weight were selected and randomly divided into 2 groups with 14 yak calves(7 males and 7 females)in each group.The yak calves in control group were only grazed,and those in the test group were fed mineral salt brick after returning to grazing.The pre-feeding period was 7 days,and the experimental period was 90 days.The results showed that the total weight gain of yak calves in the test group was significantly higher than that in the control group(P<0.05);the contents of ammonia nitrogen(days 30,60 and 90),acetic acid(days 30,60 and 90),propionic acid(days 60 and 90)and total volatile fatty acids in rumen fluid of yak calves in the test group were significantly higher than those in the control group(P<0.05);the contents of serum phosphorus(P),iron(Fe),copper(Cu),zinc(Zn),manganese(Mn)and cobalt(Co)in serum were increased in different degrees compared with the control group.It is concluded that supplementary feeding mineral salt brick in cold season can promote the growth of grazing yak calves,improve the rumen fermentation function,and increase the contents of serum P,Fe,Cu,Zn,Mn and Co.