不同脂肪的降解和吸收规律及其对奶牛瘤胃pH和NH_3-N浓度的影响

Degradability and Absorption Rules of Different Fats and Their Effects on Ruminal pH and NH_3-N Concentration in Holstein Cows

选用3头装有永久性瘤胃瘘管和十二指肠瘘管的荷斯坦奶牛,采用不完全拉丁方设计,分为日粮I(基础日粮+脂肪A400g/d)、日粮Ⅱ(基础日粮+脂肪B400g/d)、日粮Ⅲ(基础日粮+豆油400g/d)和日粮Ⅳ(基础日粮),研究脂肪A、脂肪B、豆油对瘤胃液pH值、NH3-N浓度的影响,并采用尼龙袋法研究了不同脂肪的降解吸收规律。结果表明:脂肪A、脂肪B对瘤胃pH值和NH3-N浓度无显著影响(p>0.05);豆油对瘤胃pH值无显著影响(p>0.05),但提高了瘤胃NH3-N浓度(p<0.05)。脂肪A组、脂肪B组及豆油组瘤胃48h降解率分别为0.68%、4.10%和69.93%。脂肪A组、脂肪B组及豆油组小肠最大吸收率分别为51.4%、43.1%和81.6%。

Three Holstein cows had been fitted with permanent tureen and duodenum cannula were used to study the effect of fatty acid A, fatty acid B and soybean oil in the ruminant environment with a non - complete Latin design. Every fat source was fed at 400g/d to the Holstein cows. The rules of degradability and absorption of different fats were studied using the nylon bag method. The results show that the group of fatty acid A and fatty acid B had no significant effect on the ruminal pH and NH2 - N concentrations （ p 〉 0.05 ） ; soybean oil group increased the ruminal NH3 - N concentrations significant（ p 〈 0.05 ）. After adding fatty acid A, fatty acid B and soybean oil, degradable percentage was 0.68% , 4.10% and 69.93% after 48th hours, respectively; the highest absorption rate of small intestine was 51.4% , 43.1% and 81.6% respectively.