Feeding dried distillers grains with solubles (DDGS) to lactating dairy cows has been implicated as a cause of late blowing defects in the production of Swiss-style cheeses. Our objectives were (1) to test the effect of feeding reduced-fat DDGS (RF-DDGS; ∼6% fat) to lactating dairy cows on the composition of milk and on the suitability of the milk for production of baby Swiss cheese and (2) to evaluate the effect of diet on cow lactation performance. Lactating Holstein dairy cows were fed both dietary treatments in a 2 × 2 crossover design. Cows were housed in a 48-cow freestall pen equipped with individual feeding gates to record feed intake. The control diet was a corn, corn silage, and alfalfa hay diet supplemented with mechanically expelled soybean meal. The experimental diet was the same base ration, but 20% (dry matter basis) RF-DDGS were included in place of the expelled soybean meal. The RF-DDGS diet was additionally supplemented with rumen-protected lysine; diets were formulated to be isoenergetic and isonitrogenous. Cows were allowed ad libitum access to feed and water, fed twice daily, and milked 3 times daily. For cheese production, milk was collected and pooled 6 times for each dietary treatment. There was no treatment effect on milk yield (35.66 and 35.39 kg/d), milk fat production (1.27 and 1.25 kg/d), milk fat percentage (3.65 and 3.61%), milk protein production (1.05 and 1.08 kg/d), lactose percentage (4.62 and 4.64%), milk total solids (12.19 and 12.28%), and somatic cell count (232.57 and 287.22 × 10³ cells/mL) for control and RF-DDGS, respectively. However, dry matter intake was increased by treatment, which implied a reduction in feed efficiency. Milk protein percentage also increased (3.01 and 3.11%), whereas milk urea nitrogen decreased (14.18 and 12.99 mg/dL), indicating that protein utilization may be more efficient when cows are fed RF-DDGS. No differences in cheese were observed by a trained panel except cheese appearance; control cheese eyes were significantly, but not practically, larger than the RF-DDGS cheese. These results indicate that RF-DDGS can be effectively used in the rations of lactating Holstein cows with no deleterious effects on milk production and composition and metrics of the physiology of the cow (i.e., blood glucose and nonesterified fatty acids); however, feeding RF-DDGS increased dry matter intake, which decreased feed efficiency. Finally, feeding RF-DDGS did not negatively influence quality and suitability of milk for production of baby Swiss cheese.

在瑞士风格的奶酪生产中，将干燥的酒糟和可溶物（DDGS）喂入泌乳奶牛已被认为是造成后期吹气缺陷的原因。我们的目标是（1）测试给泌乳奶牛饲喂减脂DDGS（RF-DDGS;脂肪约6％）对牛奶成分以及牛奶对瑞士婴儿奶酪生产的适应性的影响，以及（ 2）评估饮食对母牛泌乳性能的影响。哺乳的荷斯坦奶牛采用2×2交叉设计喂养两种饮食。将奶牛关在装有独立饲养口的48头牛栏内，记录采食量。对照饮食是玉米，玉米青贮饲料和苜蓿干草饮食，辅以机械排出的豆粕。实验饮食是相同的基本饮食，但是以20％（以干物质计）的RF-DDGS代替了排出的豆粕。RF-DDGS饮食中还添加了瘤胃保护的赖氨酸。日粮配制为等能量和等氮的。允许母牛自由采食和饮水，每天喂两次，每天挤奶3次。对于奶酪生产，收集牛奶，并在每次饮食处理中合并6次。对奶产量（35.66和35.39 kg / d），奶脂肪产量（1.27和1.25 kg / d），奶脂肪百分比（3.65和3.61％），奶蛋白产量（1.05和1.08 kg / d）没有处理作用，乳糖百分比（4.62和4.64％），牛奶总固形物（12.19和12.28％）和体细胞计数（232.57和287.22×10 日粮配制为等能量和等氮的。允许母牛自由采食和饮水，每天喂两次，每天挤奶3次。对于奶酪生产，收集牛奶，并在每次饮食处理中合并6次。对奶产量（35.66和35.39 kg / d），奶脂肪产量（1.27和1.25 kg / d），奶脂肪百分比（3.65和3.61％），奶蛋白产量（1.05和1.08 kg / d）没有处理作用，乳糖百分比（4.62和4.64％），牛奶总固形物（12.19和12.28％）和体细胞计数（232.57和287.22×10 日粮配制为等能量和等氮的。允许母牛自由采食和饮水，每天喂两次，每天挤奶3次。对于奶酪生产，收集牛奶，并在每次饮食处理中合并6次。对奶产量（35.66和35.39 kg / d），奶脂肪产量（1.27和1.25 kg / d），奶脂肪百分比（3.65和3.61％），奶蛋白产量（1.05和1.08 kg / d）没有处理作用，乳糖百分比（4.62和4.64％），牛奶总固形物（12.19和12.28％）和体细胞计数（232.57和287.22×10³细胞/ mL）分别用于对照和RF-DDGS。然而，通过处理增加了干物质的摄入，这意味着饲料效率的降低。牛奶中的蛋白质百分比也增加了（3.01和3.11％），而牛奶中的尿素氮减少了（14.18和12.99 mg / dL），表明当饲喂RF-DDGS的母牛时，蛋白质的利用效率更高。除奶酪外观外，由经过培训的专家组未发现奶酪的差异；对照奶酪的眼睛比RF-DDGS奶酪大得多，但实际上不大。这些结果表明，RF-DDGS可以有效地用于泌乳荷斯坦奶牛的日粮中，而对牛奶的产量，组成和奶牛生理指标（即血糖和非酯化脂肪酸）没有有害影响；但是，饲喂RF-DDGS会增加干物质的摄入量，这降低了饲料效率。最后，饲喂RF-DDGS对生产婴儿瑞士奶酪的牛奶的质量和适用性没有负面影响。