Bayat A R, Kairenius P, Stefański T, Leskinen H, Comtet-Marre S, Forano E, Chaucheyras-Durand F, Shingfield K J
Nutritional Physiology, Green Technology, Natural Resources Institute Finland (Luke), FI 31600, Jokioinen, Finland.
Nutritional Physiology, Green Technology, Natural Resources Institute Finland (Luke), FI 31600, Jokioinen, Finland.
J Dairy Sci. 2015 May;98(5):3166-81. doi: 10.3168/jds.2014-7976. Epub 2015 Feb 26.
The potential of dietary supplements of 2 live yeast strains (Saccharomyces cerevisiae) or camelina oil to lower ruminal methane (CH4) and carbon dioxide (CO2) production and the associated effects on animal performance, rumen fermentation, rumen microbial populations, nutrient metabolism, and milk fatty acid (FA) composition of cows fed grass silage-based diets were examined. Four Finnish Ayrshire cows (53±7 d in milk) fitted with rumen cannula were used in a 4×4 Latin square with four 42-d periods. Cows received a basal total mixed ration (control treatment) with a 50:50 forage-to-concentrate ratio [on a dry matter (DM) basis] containing grass silage, the same basal total mixed ration supplemented with 1 of 2 live yeasts, A or B, administered directly in the rumen at 10(10) cfu/d (treatments A and B), or supplements of 60g of camelina oil/kg of diet DM that replaced concentrate ingredients in the basal total mixed ration (treatment CO). Relative to the control, treatments A and B had no effects on DM intake, rumen fermentation, ruminal gas production, or apparent total-tract nutrient digestibility. In contrast, treatment CO lowered DM intake and ruminal CH4 and CO2 production, responses associated with numerical nonsignificant decreases in total-tract organic matter digestibility, but no alterations in rumen fermentation characteristics or changes in the total numbers of rumen bacteria, methanogens, protozoa, and fungi. Compared with the control, treatment CO decreased the yields of milk, milk fat, lactose, and protein. Relative to treatment B, treatment CO improved nitrogen utilization due to a lower crude protein intake. Treatment A had no influence on milk FA composition, whereas treatment B increased cis-9 10:1 and decreased 11-cyclohexyl 11:0 and 24:0 concentrations. Treatment CO decreased milk fat 8:0 to 16:0 and total saturated FA, and increased 18:0, 18:1, 18:2, conjugated linoleic acid, 18:3n-3, and trans FA concentrations. Decreases in ruminal CH4 production to treatment CO were related, at least in part to lowered DM intake, whereas treatments had no effect on ruminal CH4 emission intensity (g/kg of digestible organic matter intake or milk yield). Results indicated that live yeasts A and B had no influence on animal performance, ruminal gas production, rumen fermentation, or nutrient utilization in cows fed grass silage-based diets. Dietary supplements of camelina oil decreased ruminal CH4 and CO2 production, but also lowered the yields of milk and milk constituents due to an adverse effect on intake.
研究了两种活酵母菌株（酿酒酵母）或亚麻荠油作为膳食补充剂降低瘤胃甲烷（CH₄）和二氧化碳（CO₂）产生的潜力，以及对以青贮草为基础日粮的奶牛的生产性能、瘤胃发酵、瘤胃微生物种群、营养物质代谢和乳脂肪酸（FA）组成的相关影响。选用4头装有瘤胃瘘管的芬兰艾尔夏奶牛（产奶53±7天），采用4×4拉丁方设计，共4个42天的试验期。奶牛接受基础全混合日粮（对照处理），青贮草占饲粮与精料比为50:50（干物质基础），或在基础全混合日粮中添加两种活酵母之一A或B，以10¹⁰ cfu/d的剂量直接注入瘤胃（处理A和B），或添加60g亚麻荠油/kg饲粮干物质，替代基础全混合日粮中的精料成分（处理CO）。与对照相比，处理A和B对干物质采食量、瘤胃发酵、瘤胃气体产生或表观全消化道养分消化率无影响。相反，处理CO降低了干物质采食量以及瘤胃CH₄和CO₂的产生，这些反应与全消化道有机物消化率的数值非显著下降有关，但瘤胃发酵特性无改变，瘤胃细菌、产甲烷菌、原生动物和真菌总数也无变化。与对照相比，处理CO降低了牛奶、乳脂、乳糖和蛋白质的产量。与处理B相比，处理CO由于粗蛋白摄入量较低而提高了氮利用率。处理A对乳脂肪酸组成无影响，而处理B增加了顺式-9 10:1的含量，降低了11-环己基11:0和24:0的浓度。处理CO降低了乳脂中8:0至16:0以及总饱和脂肪酸的含量，并增加了18:0、18:1、18:2、共轭亚油酸、18:3n-3和反式脂肪酸的浓度。处理CO使瘤胃CH₄产生量降低，至少部分与干物质采食量降低有关，而各处理对瘤胃CH₄排放强度（g/kg可消化有机物摄入量或产奶量）无影响。结果表明，活酵母A和B对以青贮草为基础日粮的奶牛的生产性能、瘤胃气体产生、瘤胃发酵或养分利用无影响。亚麻荠油作为膳食补充剂降低了瘤胃CH₄和CO₂的产生，但由于对采食量有不利影响，也降低了牛奶和乳成分的产量。
