体外法研究不同磷添加水平对奶牛瘤胃内pH和挥发性脂肪酸的影响

Effects of Different Inorganic Phosphorus Adding Levels on pH and Volatile Fatty Acid in Dairy Cows in vitro

采用体外法研究无机磷添加浓度对瘤胃发酵的影响。无机磷在培养液中设0、30、60、90、120、150、200、250、300、350 mg/L 10个水平。体外培养发酵48 h后终止培养,测定培养液的pH、总挥发性脂肪酸(VFA)。结果表明,不同无机磷添加水平对乙酸、丙酸、丁酸和总VFA产量影响显著(P<0.05),无机磷添加水平为200 mg/L时,乙酸、丙酸、丁酸及总VFA产量最高,随后下降。瘤胃培养液pH随无机磷添加水平的增加而显著降低(P<0.05),无机磷添加水平为200 mg/L时达到最小值5.65,随后又上升。在本试验条件下,添加无机磷明显促进瘤胃微生物对饲料养分的发酵,适宜添加水平为200 mg/L。

The effects of rumen fermentation by adding inorganic phosphorus in vitro were studied,Concentration of inorganic phosphorus were 0,30,60,90,120,150,200,250,300 and 350 mg/L.The pH and volatile fatty acid（VFA） of 48 h fermentation in vitro were measured.The results as follows： Acetate,propionate,butyrate acid and total VFA production were significantly effected by the concentration of inorganic phosphorus（P0.05）.Acetate,propionate,butyrate acid and total VFA production were the highest when the concentration of inorganic phosphorus was 200 mg/L.pH was significantly influenced by different inorganic phosphorus levels（P0.05）.pH decreased when inorganic P levels increased（P0.05）and reached its minimum when inorganic phosphorus was 200 mg/L.In this experiment the optimum adding levels of inorganic phosphorus was 200 mg/L.