The objective of this study was to evaluate the effect of selenium-enriched Saccharomyces cerevisiae on the performance, composition and quality of milk from cows fed diets containing dried malt bagasse. Eight Holstein cows were distributed in a 4 × 4 double Latin square. The treatments were in a 2 × 2 factorial scheme: with or without the inclusion of malt bagasse x with or without the addition of selenium-enriched Saccharomyces cerevisiae. Dried malt bagasse was included at 24% in the dry matter (DM) of the diet; the amount of yeast supplied was 15 g/day and was composed of strain Saccharomyces cerevisiae CNCM I-1077 containing 1.0 × 10⁹ CFU/g and 170 mg selenium/kg. Cows fed diets containing malt bagasse presented lower intakes of DM, crude protein and non-fibrous carbohydrates (NFC) and higher intakes of ethereal extract and neutral detergent fiber (P < 0.05). The digestibility of DM and the NFC of the diets with malt bagasse were lower in relation to the diets without this ingredient (P < 0.01). The addition of yeast did not influence the intake and digestibility of nutrients or any blood parameters. The levels of cholesterol and triglycerides of cows fed malt bagasse were higher than those that did not receive this by-product (P < 0.01). There was an interaction for blood urea, wherein the concentrations of the malt bagasse diet were higher than the diets without bagasse and without bagasse with yeast (P < 0.05). Cows fed diets without malt bagasse and with yeast produced more microbial protein than those fed with malt bagasse and yeast (P < 0.05). The use of selenium-enriched Saccharomyces cerevisiae had no effect on the production, composition and oxidative stability of the milk, but increased the milk selenium concentration (P < 0.05). The inclusion of malt bagasse reduced energy-corrected milk production, fat, protein, casein and total solids content of milk (P < 0.05), and increased milk urea nitrogen and the conjugated diene concentration (P < 0.01). Thus, the use of selenium-enriched Saccharomyces cerevisiae in the diet of lactating cows increased the selenium concentration, but did not improve the production and oxidative stability of the milk, whereas the inclusion of dried malt bagasse reduced energy intake, energy-corrected milk production and the milk fat and protein contents.

这项研究的目的是评估富含硒的酿酒酵母对饲喂含有干麦芽蔗渣的奶牛的牛奶性能，组成和品质的影响。八头荷斯坦奶牛分布在4×4的双拉丁方格中。处理采用2×2阶乘方案：加或不加麦芽蔗渣x，加或不加富硒啤酒酵母（Saccharomyces cerevisiae）。日粮干物质（DM）中包含24％的干麦芽蔗渣；酵母的每日供应量为15 g /天，由含有1.0×10 ^9的酿酒酵母CNCM I-1077组成CFU / g和170 mg硒/ kg。饲喂含麦芽蔗渣日粮的母牛摄入的DM，粗蛋白和非纤维性碳水化合物（NFC）较低，而醚提取物和中性洗涤剂纤维的摄入量较高（P <0.05）。麦芽蔗渣日粮中的DM和NFC的消化率相对于不含该成分的日粮而言较低（P <0.01）。添加酵母不会影响营养物质的摄入和消化率或任何血液参数。饲喂麦芽蔗渣的母牛的胆固醇和甘油三酸酯水平高于未接受这种副产物的母牛（P <0.01）。血尿素之间存在相互作用，其中麦芽蔗渣日粮的浓度高于无蔗渣日粮和无酵母的蔗渣日粮（P <0.05）。饲喂不含麦芽蔗渣和酵母的日粮比饲喂麦芽蔗渣和酵母的牛产生更多的微生物蛋白（P <0.05）。使用富硒酿酒酵母对牛奶的生产，组成和氧化稳定性没有影响，但增加了牛奶中的硒浓度（P <0.05）。麦芽蔗渣的加入降低了能量校正后的牛奶产量，牛奶中的脂肪，蛋白质，酪蛋白和总固形物含量（P <0.05），并增加了牛奶尿素氮和共轭二烯浓度（P <0.01）。因此，在泌乳母牛的饮食中使用富含硒的酿酒酵母增加了硒的浓度，但并未提高牛奶的产量和氧化稳定性，而包含干麦芽蔗渣则降低了能量摄入，通过能量校正了牛奶的产量。以及牛奶中的脂肪和蛋白质含量。