葡萄籽精油对体外瘤胃发酵和甲烷生成的影响

通过体外培养法研究发酵底物精粗比7∶3条件下,添加100,150和250μL/L葡萄籽精油对瘤胃发酵和甲烷产量的影响。采用气相色谱仪测定甲烷产量,培养24 h后,测定挥发性脂肪酸、pH、氨态氮浓度和原虫数。结果发现,添加葡萄籽精油100μL/L和150μL/L与对照组相比提高累计产气量、发酵液pH值(P<0.05)、乙酸摩尔比例,降低甲烷浓度(P<0.01)、丙酸、丁酸、戊酸和支链挥发性脂肪酸摩尔比例。葡萄籽精油添加量为150μL/L降低氨态氮浓度及瘤胃原虫数,添加100μL/L葡萄籽精油提高总挥发性脂肪酸。试验表明,适宜添加量的葡萄籽精油可以改变瘤胃发酵模式,增加丙酸乙酸比例,抑制甲烷生成。

Effects of grape seed oil addition on rumen fermentation and methanogenesis in vitro

A diet of 7 concentrate: 3 forage was used as substrate in vitro,treatments were consisted of control group(0) versus three levels of grape essential oils(100,150,250 μL/L),3 repeats in each group.In vitro gas production(GP) was recorded and methane production was determined 3,6,9,12 and 24 h after incubation.Ammonia nitrogen,volatile fatty acids(VFAs),protozoa and pH were measured after 24 h incubation.The results showed that the gas production,pH and acetate proportion were increased by supplementations of 100 and 150 μL/L grape seed oils(P<0.05),where the methane production(P<0.01),molar proportion of propionate,butyrate,valerate and BCVFA decreased.In addition,ammonia nitrogen and protozoa were decreased by supplementation of 150 μL/L grape seed oils,while,total volatile fatty acid increased by 100 μL/L grape seed oils.In conclusion,addition of grape seed oils at a proper level could change the fermentation pattern,increase the propionate acetate ratio and inhibit methanogenesis.