Four multiparous dairy cows were used in a 4 × 4 Latin square to examine how starch level and oil mixture impact dry matter (DM) intake and digestibility, milk yield and composition, rumen fermentation, ruminal methane (CH₄) emissions, and microbial diversity. Experimental treatments comprised high (HS) or low (LS) levels of starch containing 0 or 30 g of a mixture of sunflower and fish oils (2:1 w/w) per kg diet DM (LSO and HSO, respectively). Intake of DM did not differ between cows fed LS and HS diets while oil supplementation reduced DM intake. Dietary treatments did not affect milk and energy corrected milk yields. There was a tendency to have a lower milk fat concentration due to HSO compared with other treatments. Both high starch level and oil supplementation increased digestibility of gross energy. Cows receiving HS diets had higher levels of total rumen VFA while acetate was lower than LS without any differences in rumen pH, or ruminal CH₄ emissions. Although dietary oil supplementation had no impact on rumen fermentation, decreased CH₄ emissions (g/day and g/kg milk) were observed with a concomitant increase in Anoplodinium-Diplodinium sp. and Epidinium sp. but a decrease in Christensenellaceae, Ruminococcus sp., Methanobrevibacter ruminantium and Mbb. gottschalkii clades.

中文翻译：

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淀粉水平以及向日葵和鱼油的混合物对奶牛养分摄入和消化率、瘤胃发酵和瘤胃甲烷排放的影响


在 4 × 4 拉丁方中使用四头经产奶牛来研究淀粉水平和油混合物如何影响干物质 (DM) 摄入量和消化率、产奶量和成分、瘤胃发酵、瘤胃甲烷 (CH ₄ ) 排放和微生物多样性。实验处理包括高（HS）或低（LS）水平的淀粉，每公斤饮食DM（分别为LSO和HSO）含有0或30克向日葵和鱼油（2:1 w / w ）的混合物。饲喂 LS 和 HS 日粮的奶牛的 DM 摄入量没有差异，而补充油则减少了 DM 摄入量。饮食治疗不影响产奶量和能量校正产奶量。与其他处理相比，HSO 导致乳脂浓度有降低的趋势。高淀粉含量和补充油都增加了总能量的消化率。接受 HS 日粮的奶牛的瘤胃总 VFA 水平较高，而醋酸盐水平低于 LS，但瘤胃 pH 值或瘤胃 CH ₄排放量没有任何差异。虽然膳食油补充对瘤胃发酵没有影响，但观察到 CH ₄排放量（g/天和 g/kg 牛奶）减少，同时Anoplodinium-Diplodinium sp 增加。和Epidinium sp。但Christensenellaceae 、 Ruminococcus sp.、 Methanobrevibacter ruminantium和Mbb 有所减少。戈特沙尔基分支。