甜菜碱对奶牛采食量、泌乳性能和血液指标的影响

Effects of betaine supplementation on feed intake, lactation performance and blood parameters in dairy cows

选用20头体重(597±11.8)kg、泌乳天数(88±4.5)d、日产奶(26.3±0.5)kg的经产奶牛,随机分为4组,采用4×4拉丁方设计,研究甜菜碱(0、50、100和150g/d)对泌乳早期奶牛采食量、泌乳性能和血液指标的影响。结果表明:日粮添加甜菜碱对奶牛的采食量、乳蛋白率、乳糖率和血糖浓度无显著影响,100g/d组和150g/d组鲜奶产量显著高于对照组和50g/d组(P<0.05);100g/d组和150g/d组4%乳脂校正乳、能量校正乳和乳脂产量显著高于对照组(P<0.05);100g/d组乳脂率显著高于对照组(P<0.05);100g/d组和150g/d组血浆游离脂肪酸和β-羟丁酸浓度显著低于对照组(P<0.05)。根据以上结果推断,甜菜碱的适宜添加水平为100g/d。

Twenty muhiparous Holstein dairy cows （597±11.8） kg of BW, （88±4.5） days in milk and average daily milk production of （26.3±0.5） kg/cow） were used in a replicated 4 ×4 Latin square experiment to evaluate the effects of betaine supplementation （0, 50, 100 and 150 g/d） on feed intake, lactation performance and blood parameters in dairy cows. The results showed that average feed intake, milk protein percentage, milk lactose percentage and blood glucose concentration were not affected significantly by betaine supplementation （P〉0.05）. Milk yield, 4% fat-corrected milk yield, energy- corrected milk yield and milk fat yield of the 100 g/d and 150 g/d betaine supplementation treatments were higher than those of the control （P〈0.05）. Milk fat percentage of the 300 g/d treatment was higher than control （P〈0.05）. Cows receiving 100 g/d and 150 g/d betaine had a lower plasma NEFA and β- hydroxybutyrate than those of the contol （P 〈0.05）. Results of the present study indicated that the optimum dose of betaine supplementation was 100 g/d.