开食料中粗蛋白质水平对荷斯坦犊牛瘤胃发育的影响  

Effects of Crude Protein Levels in Starters on Rumen Development of Holstein Bull Calves

作　　者：云强[1] 刁其玉[1] 屠焰[1] 周怿[1] 

机构地区：[1]中国农业科学院饲料研究所,北京100081

出　　处：《动物营养学报》2010年第1期57-62,共6页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家科技支撑计划子课题"奶牛营养调控及高效饲养技术研究"(2006BAD04A03-03);所属课题名称"奶业发展重大关键技术研究与示范"

摘　　要：本试验旨在研究开食料中粗蛋白质水平对断奶犊牛瘤胃发酵、微生物酶活性及瘤胃发育的影响。试验选取15头荷斯坦公犊牛,分别饲喂粗蛋白质水平为16.22%、20.21%和24.30%的开食料。开食料采用限饲,试验在犊牛的8～16周龄进行。在犊牛12周龄晨饲3 h后通过瘤胃导管、16周龄晨饲前通过屠宰采集瘤胃液以研究瘤胃发酵、吸收能力和微生物酶活性。16周龄时对犊牛进行屠宰,取瘤胃组织样品以研究瘤胃上皮细胞发育情况。结果表明,高蛋白质组的瘤胃液pH在12周龄时较低,但在16周龄时则较高。高蛋白质组的氨态氮浓度和挥发性脂肪酸浓度要高于其他2组(P>0.05)。中蛋白质组的α-淀粉酶活性要低于其他2组(P>0.05)。蛋白酶和纤维素酶活性随开食料中粗蛋白质水平的升高而升高,同一组16周龄时要高于12周龄(P>0.05)。瘤胃发育结果表明,犊牛在16周龄时,中蛋白质组的瘤胃相对重量在3个组中最低。低蛋白质组的瘤胃乳头长度和黏膜厚度要高于中蛋白质组和高蛋白质组(P>0.05),但是中蛋白质组的瘤胃乳头宽度在3组中最大。由以上结果可知,开食料中粗蛋白质水平对8～16周龄犊牛瘤胃发酵、微生物酶活性和瘤胃发育没有显著影响(P>0.05),但高水平的粗蛋白质有提高瘤胃的发酵能力和微生物酶活性的趋势。This trial was designed to study the effects of crude protein levels in starters on rumcn fermentation, enzymes activity of rumcn microorganisms and rumen development of weaned calves. Fifteen Holstein bull calves were fed starters containing 16.22% （low protein content, group LP）, 20.21% （medium protein content, group MP） and 24.30% （high protein content, group HP） crude protein, respectively. Starters were limited fed to calves from 8 to 16 wk of age. The rumen fluid was taken out by rumen duct at age of 12 wk after feeding 3 h and by euthanized at age of 16 wk before feeding to investigate rumen fermentation, absorbability and enzymes activity. All calves were euthanized at 16 wk of age and rumen tissue was sampled for rumen epithelial development measurements. The results indicated that calves in group HP had low rumen pH at 12 wk but high rumen pH at 16 wk. There were higher ammonia nitrogen concentrations and rumen volatile fatty acid concentrations in calves fed starter with HP than those in calves fed other starters （P〉0.05）. The α-amylase activity was lower in calves that fed MP starter than that fed other starters （P〉0.05）. The protease and cellulases activities tended to be increased as the crude protein content increase in starters and was higher in 16 wk than in 12 wk in the same group（P〉0.05）. The result of rumen development indicated that the rumen relative weight of calves in group MP was the lowest in all calves at 16 wk. The papillae length and rumen mueosa thickness of group LP were higher than that in groups MP and HP （P〉 0.05）. However, the papillae width of the calves fed starter with MP was the greatest. To sum up, There were not significant effects on rumen fermentation, rumen microorganisms enzyme activity and rumen development to calves fed different crude protein levels of starters from 8 to 16 wk（P〉0.05）. But high crude protein level seemed to increase the rumen fermentation ability and microorganisms enzyme activity.

关 键 词：犊牛 开食料 粗蛋白质水平 瘤胃发酵 微生物酶活性 瘤胃发育 

分 类 号：S823[农业科学—畜牧学] S816.4[农业科学—畜牧兽医]