日粮添加豆油和胡麻油对肉牛瘤胃发酵及主要微生物数量的影响

 【目的】评价日粮添加植物油对瘤胃发酵和瘤胃微生物区系的影响。【方法】采用3×3拉丁方设计，用3头装有永久性瘤胃瘘管的杂交肉牛研究不添加油脂（对照组）、添加4％豆油（豆油组）或4％胡麻油（胡麻油组）对瘤胃pH值、NH3-N浓度、VFA以及瘤胃细菌和原虫的影响。3组日粮精粗比均为35﹕65，每期试验为21d，共3期。【结果】添加油脂对瘤胃内pH值没有影响(P＞0.05)；对照组和胡麻油组瘤胃NH3-N浓度显著高于豆油组(P＜0.05)；与对照组相比，豆油组和胡麻油组显著降低了瘤胃乙酸、丙酸、丁酸、总挥发性酸浓度以及总细菌、蛋白分解菌、纤维分解菌及原虫的数量(P＜0.05)，但对乙酸与丙酸比例以及淀粉分解菌数量两个指标组间无显著差异(P＞0.05)。对照组、豆油组和胡麻油组纤维分解菌和原虫的数量依次分别为6.79×108、5.71×108、5.92×108；10.67×104、7.11×104、9.56×104 CFU•ml-1；两个加油组显著降低了瘤胃纤维分解菌和原虫数(P＜0.05)。【结论】日粮添加4％豆油和胡麻油对瘤胃发酵及主要微生物都有一定的抑制效应，但二者抑制效应大小无显著差异。

Effects of Soybean Oil and Linseed Oil Supplementation on the Rumen Fermentation and Main Rumen Microflora of Cattle

Abstract: Three rumen-fistulated hybrid yellow cattle were randomly assigned according to a 3×3 Latin square design to investigate effects of supplementation oil in concentrates on pH, NH3-N, VFA and rumen microflora. The dietary treatments were 65% rough and 35% concentrate-based, containing 0 (control), 4% soybeam oil (soybean oil treatment) and 4% linseed oil (linseed oil treatment) of DMI, respectively. The experiment was conducted for three periods, each period lasting 21 days. The results indicated that ruminal pH value was not significantly affected by supplementing oil (P＞0.05). NH3-N concentrates in control and linseed oil treatment were significantly higher than soybean oil treatment (P<0.05). Compared with control group, acetate, propionate, butyrate and total VFA concentration, total viable bacteria, proteolytic bacteria, cellulytic bacteria and protozoa in soybean oil and linseed oil treatments were dramatically lower than the control group. However, there were not significant differences on acetate to propionate ratio and amylolytic bacteria by supplementing oil.