乳牛代谢病的研究 Ⅱ.不同营养水平对乳牛脂代谢的影响

Study on Metabolic Diseases in Cows Ⅱ. The Influence of Dietary Nutrition Levels on Lipid Metabolism in Cows

12头成年泌乳牛随机分3组,分别喂以高、中、低含量的精料;8头16月龄母牛随机分成2组,一组主要以青干草为粗料,另一组主要以棉籽壳为粗料。试验期为15个月,每3个月采血一次,测定血清甘油三酯、胆固醇、磷脂和全血酮体及乳脂等。结果表明,高精料组牛较其它二组成年牛肥胖。TG、PL、Chol显著高于其它二组。棉籽壳组较青干草组明显肥胖,第一胎时的产乳量和乳脂率低于后者,两组问TG、Chol、PL和Ketones无显著差异。棉籽壳组有2头牛在试验期间发生了真胃左方变位。

Tewlve black and white cows were randomly divided into three groups and fed with high-, medium- or low-concentrate diets respectively. Eight 16-month-old heifers were randomly divided into two groups and one group was fed with hay as roughage and the other with cotton seed hulls. The experiment lasted 15 months. Blood was taken from Jugular Vein of each cow or calf every 3 months. Serum TG, Chol, PL, whole blood Ketones and milk fat were determined. Cows fed with high concentrate diets were fatter than those fed moderate or low concentrate and serum TG, PL and Chol concentrations of the cows fed with high concentrate diets were significantly higher than that of other. Heifers fed with cotton seed hulls were fatter than those fed with green grass and hay. Milk production and milk fat levels of the former were significantly lower than that of the latter. But no differences have been found in serum TG, Chol, PL and Ketones between both exprimental groups. Two heifers fed cotton seed hulls sulffered from left displacement of the abomasum.