非乳源性蛋白对奶牛犊牛早期断奶体重和前胃发育的影响

Effects of Non-milk Protein on Body Weight and Forestomach Development of Dairy Calves at Early-weaning Stage

为中国荷斯坦牛犊牛早期断奶的人工培育、公犊牛的肉牛资源化利用提供参考,选择品种来源一致、出生时间不超过3d的中国荷斯坦公犊30头,分别采用40%、55%和70%的非乳源性蛋白替代代乳料中乳源性蛋白,以改性植物蛋白、改性淀粉分别为早期断奶代乳料的蛋白质和能量的主要来源,实现全乳哺喂量仅98.96kg,3周龄早期断奶,研究非乳源性蛋白不同比例对乳用犊牛早期断奶体重和前胃发育的影响。结果表明:70%非乳源性蛋白替代组的犊牛,4周龄时瘤胃pH已达到成年牛的中性微酸水平,并维持相对稳定,为瘤胃微生物区系的发育提供了稳定的瘤胃环境;8周龄时体重为80.13kg,平均日增重为651g,前胃重量、容积和瘤胃纤毛虫数量接近正常成年牛的水平,均与40%、55%非乳源性蛋白替代组的效果相当。说明,中国荷斯坦牛犊牛早期断奶代乳料中70%的非乳源性蛋白替代可取得良好的增重效果,能有效促进前胃的提早发育和瘤胃pH环境的提早形成,从而促进瘤胃微生物区系的提早建立。

30Chinese Holstein bull calves within 3dold from the same source were fed with 40%,55% and 70% non-milk protein instead of milk protein to study effects of non-milk protein with different proportion on body weight and forestomach development of dairy calves at early-weaning stage and to provide a reference for artificial breeding of Chinese Holstein calves at early-weaning stage and beef resource utilization of bull calves.The rumen pH of calves with 4 weeks old fed with 70% non-milk protein reaches the neutral and slight acidic level of adult cattle and maintains the relatively stable,which provides a stable rumen environment for development of rumen microflora.The body weight of a calf with8 weeks old is up to 80.13 kg with 651 g of average daily gain,and the forestomach weight,forestomach volume and rumen ciliate number are similar to the levels of normal adult cattle.There is no difference in body weight and rumen development among 40%,55%and 70% non-milk protein groups,which indicates that 70% non-milk protein can effectively increase body weight and promote early development of forestomach and rumen pH environment of calves at early-weaning stage to help establishment of rumen microflora early.