丙酸镁对西门塔尔牛瘤胃液pH和氨态氮浓度的影响

Effects of supplemental magnesium propionate on ruminal pH and ammonia concentration in Simmental steer

选用4头3.5岁、体况良好(500±20)kg的中国西门塔尔牛阉牛,采用4×4拉丁方设计,研究日粮添加丙酸镁(100g/d)、丙酸(87g/d)和氧化镁(24g/d)对西门塔尔牛瘤胃液pH和氨态氮(NH3-N)浓度的影响。结果表明:日粮添加丙酸镁、丙酸和氧化镁后,0h各组间pH差异不显著(P>0.05),3h、6h丙酸镁和丙酸组pH较对照组和氧化镁组显著降低(P<0.05),9h丙酸镁组pH与其他三组差异不显著(P>0.05),丙酸镁组和丙酸组pH平均值较对照组和氧化镁组显著降低(P<0.05);0h和9h各组间瘤胃液NH3-N浓度差异不显著(P>0.05),3h和6h丙酸镁组瘤胃液NH3-N浓度显著低于其他组(P<0.05),丙酸镁组瘤胃液NH3-N浓度平均值显著低于其他组(P<0.05)。本试验条件下,日粮中添加丙酸镁可降低西门塔尔牛瘤胃液pH和NH3-N浓度。

Four Simmental steers with average body weight （500±20）kg,aged 3.5,cannulated at the rumen,were used in a 4×4 Latin square design to evaluate the effects of supplemental magnesium propionate（MgP, 100 g/d） ,propionic acid （PA,87 g/d）and magnesium oxide （MgO,24 g/d）on ruminal pH and ammonia concentration.The results showed that there was no significant difference on ruminal pH at 0 h when steers supplemented with MgP,PA and MgO （P 〉 0.05）. Ruminal pH of MgP and PA groups were lower than that of control and MgO group at 3 h and 6 h significantly （P 〈 0.05） ,but MgP group had no difference compared with other three groups at 9 h （P 〉 0.05）.The average ruminal pH of MgP and PA group were lower than that of control and MgO group significantly （P 〈 0.05 ）.There was no difference of ruminal ammonia concentration in all groups at 0 h and 9 h（P 〉 0.05）.Ruminal ammonia concentration of MgP group at 3 h and 6 h was lower than that of other groups significantly （P 〈 0.05）.The average ruminal ammonia concentration of MgP group was significant lower than that in other three groups （P 〈 0.05）.It can be concluded that magnesium propionate could decrease the ruminal pH and ammonia concentration in Simmental steer.