低蛋白精料补充料对奶牛生产性能和繁殖性能的影响

Effects of Low Protein Concentrate Supplenment on Productive and Reproductive Performance in Dairy Cows

适宜的奶牛日粮蛋白质营养水平和来源是保证泌乳奶牛生产性能发挥的重要条件,蛋白含量过高会导致养殖成本增大和生态环境污染。选用体况良好、产奶量(28 kg/d)和泌乳天数均接近的泌乳奶牛30头,平均分成2组,用精料补充料、带穗青贮、苜蓿和全株燕麦配制而成的奶牛全混合日粮(营养水平达到NY/T 34—2004)进行饲喂。采用单因素对比试验设计,精料补充料蛋白质含量设17.5%(低水平,试验组)和19.0%(高水平,对照组) 2个处理,试验期4个月,每天上料2次,奶牛自由采食、自由饮水,研究了低蛋白精料补充料对泌乳奶牛生产性能、繁殖性能和经济效益的影响。结果表明:与高蛋白精料补充料相比,采用低蛋白精料补充料对泌乳奶牛的生产性能和繁殖性能影响均不显著,但可明显降低奶牛子宫炎的发病率,并降低奶牛的饲养成本。对于产奶量在28 kg/d左右的泌乳奶牛,日粮提供的精料补充料蛋白质含量达到17.5%即可满足其营养需要。

The suitable dietary protein level and sources are important factors to ensure productive performance of lactating dairy cows. High protein will lead to the increase of breeding cost and pollution of ecological environment. Thirty health lactating cows with similar milk yield and days of lactation were selected and randomly divided into two equal number groups. The TMR was made up of concentrate supplement,silage with ear,alfalfa and whole-plant oat. The single factor contrast experiment design was used. The protein content of concentrate supplement was 17.5%(low level,test group) and 19.0%(high level,control group),respectively.Cows were fed twice a day for four months,and feed and water were provided ad libitum. The effects of low protein concentrate supplenment on productive performance,reproductive performance and economic benefits of dairy cows were studied. The results showed that low protein concentrate supplenment had no significant influence on productive performance and reproductive performance of dairy cows,but the metritis of dairy cows significantly decreased,and the feeding cost declined. The low protein concentrate supplenment level of 17.5%diets could meet the nutritional needs of lactating dairy cows with milk production of 28 kg/d.