后备牛蛋白质营养需要研究进展

为培育优质泌乳奶牛,研究不同生理阶段后备牛日粮的最佳蛋白质水平。采用生长比较试验、消化代谢试验和屠宰试验研究蛋白质水平对后备牛的影响。结果表明,①0～2月龄哺乳期犊牛,代乳粉中粗蛋白水平22%为宜;②3～4月龄断奶犊牛,开食料中粗蛋白水平20%最佳;③8～10月龄后备母牛,在日粮消化能为13.17MJ/kg时,粗蛋白水平约12%,蛋白能量比为37.9:1(g/Mcal),可满足ADG为0.9kg/d时的生长需要。结论,蛋白水平对后备奶牛的生长发育非常重要。

A Review: Development for the requirement of young cattle to crude protein level in diets

To cultivate high-quality dairy cows, the best protein level in diets for different physiological stages of young cattle was studied. Comparison experiment, metabolism trial and slaughter test were used in the program. ①The results showed that 0 to 2 month old calves, 22% of crude protein level in milk replacer was appropriate; ②3～4 months old weaned calves, 20% crude protein level in starter ration was the best; ③8～10 months old heifer, 12% CP level, DE level 13.17 MJ/kg and the CP to DE ratio 37.9: 1 (g/Mcal) in the diet could meet the requirement of daily gain about 0.9 kg. Conclusions, CP levels had a great effect on growth and development of different physiological stages of young cattle.