日粮营养水平对肉用育成母牛生长发育、血清生化指标及肠道菌群的影响

on growth and development,serum biochemical indices and intestinal flora of growing cows

试验旨在研究不同能量蛋白质水平的日粮对育成期母牛的生长发育、血清生化指标及肠道菌群的影响。选取24头10月龄左右,平均体重为275.54 kg的西门塔尔育成期母牛,随机分为3组,每组8个重复,每个重复1头牛。对照组(CON组)日粮的代谢能(ME)为9.96 MJ/kg,粗蛋白(CP)为11.7%;高能量组(ENE组)日粮的ME为10.93 MJ/kg,CP为11.7%;高蛋白质组(PRO组)日粮的ME为9.96 MJ/kg,CP为12.9%。预试期15 d,正式试验期60 d。结果表明,不同日粮营养水平对母牛的干物质采食量(DMI)、平均日增重(ADG)无显著影响(P>0.05)。PRO组母牛的胸围显著高于ENE组(P<0.05),PRO组和CON组母牛的十字部高显著高于ENE组(P<0.05)。PRO组和ENE组母牛血清尿素氮含量显著低于CON组(P<0.05),PRO组母牛总胆固醇含量和谷丙转氨酶活性显著低于CON组(P<0.05)。拟杆菌门(Bacteroidetes)和厚壁菌门(Firmicutes)在3组中丰度均最高,3组中属水平上丰度排名前三的是瘤球菌科UCG-005(UCG-005)、理研菌科_RC9肠道群(Rikenellaceae_RC9_gut_group)、未知属f型_UCG_010(norank_f_UCG-010)。研究表明,提高育成母牛日粮中蛋白质水平比提高能量水平对育成期肉用母牛的生长、营养代谢以及吸收具有更好的作用。

The experiment was to study the effect of different energy and protein levels on growth and development,serum biochemical indices and intestinal flora of growing cows.Twenty-four Simmental 10-month-old cows with an average body weight of 275.54 kg were randomly divided into three groups,with eight replicates in each group and one cow in each replicate.The ME and CP of control group(CON group)diet was 9.96 MJ/kg,11.7%,ME and CP of high-energy group(ENE group)diet was 10.93 MJ/kg,11.7%,ME and CP of high protein group(PRO group)diet was 9.96 MJ/kg,12.9%.The pre-trial period lasted for 15 d,and the experimental period lasted for 60 d.The results showed that different dietary nutrient levels had no significant effect on DMI,ADG of cows(P>0.05).The chest girth of cows in PRO group was significantly higher than that in ENE group(P<0.05),and the cross height in PRO group and CON group was significantly higher than that in ENE group(P<0.05).The serum urea nitrogen content in PRO group and ENE group was significantly lower than that in CON group(P<0.05),and the total cholesterol content and glutamic-pyrulol transaminase activity in PRO group were significantly lower than those in CON group(P<0.05).Bacteroidetes and Firmicutes were the most abundant in three groups.The top three genera in the three groups were UCG-005(UCG-005),Rikenellaceae_RC9_gut_group(Rikenellaceae_RC9_gut_group)and the unknown genus f-type UCG_010(norank_f_UCG-010).The experiment indicates that increasing dietary protein level has better effect on growth,nutrient metabolism and absorption of beef cows during growing period than increasing energy level.