The objective of this study was to evaluate increasing levels of inclusion of dry distillery grains (DDGs) in substitution of corn and urea in multiple supplements for beef cattle of Urochloa brizantha cv. Marandu on the consumption, digestibility, and efficiency of microbial synthesis and use of nitrogen. We used four Nellore bulls cannulated in the rumen with an average age of 24 months and 445.12 ± 34.4 kg of body weight (BW), in a 4 × 4 Latin square design. Supplements differed by the inclusion level of DDG (0%, 31.5%, 63.0%, and 94.5%). Increasing levels of DDG inclusion decreased dry matter intake (DMI) (P = 0.002), forage (P = 0.002), organic matter (OM) (P = 0.001), crude protein (CP) (P = 0.037), and total digestible nutrients (TDN) (P < 0.001) and had a quadratic effect on the intake of non-fibrous carbohydrates (NFC) (P = 0.002). It was observed an increase in the digestibility of ether extract (EE) (P = 0.005), however a decrease in the digestibility of NFC (P = 0.001). Inclusion of DDG did not influence ruminal pH. There was a quadratic effect at collection times for ruminal ammoniacal nitrogen (P < 0.05), except for the supplement with 94.5% DDG where the effect was linear (P = 0.002). Nitrogen intake was 10.9% higher when there was no DDG in the supplement, compared with the supplement with 94.5% DDG (P = 0.039). The excretion of N by feces was greater when there was a greater amount of DDG in the supplement (P = 0.027), the opposite occurred with urine excretion of N, being higher when there was less amount of DDG in the supplement (P = 0.027). Increasing levels of DDG did not affect ruminal microbial protein yield (P > 0.05). Replacing corn and urea with up to 94.5% DDGs in multiple supplements resulted in no adverse effect efficiency of microbial synthesis, although nutrient intake, total digestible nutrients, and use of nitrogen were reduced at 94.5% DDG inclusion.

这项研究的目的是评估在添加Urochloa brizantha cv的牛的多种补品中，用干酒糟（DDG）替代玉米和尿素的含量增加的情况。Marandu涉及微生物合成和利用氮的消耗，消化率和效率。我们采用了4头拉丁方形设计，在瘤胃中插管了4头Nellore公牛，平均年龄为24个月，体重（BW）为445.12±34.4千克。补充剂的DDG含量不同（0％，31.5％，63.0％和94.5％）。DDG夹杂物增加水平降低的干物质摄取量（DMI）（P  = 0.002），草料（P  = 0.002），有机物（OM）（P  = 0.001），粗蛋白（CP）（P = 0.037）和总可消化营养素（TDN）（P  <0.001），对非纤维碳水化合物（NFC）的摄入具有二次效应（P  = 0.002）。观察到醚提取物（EE）的消化率增加（P  = 0.005），而NFC的消化率下降（P  = 0.001）。包含DDG不会影响瘤胃pH。瘤胃氨氮的收集时间有二次效应（P  <0.05），但补充剂中DDG含量为94.5％时呈线性关系（P  = 0.002）。补充剂中不含DDG时，氮摄入量高10.9％，而补充剂中DDG则为94.5％（P = 0.039）。当补充物中DDG的量较大时，粪便中N的排泄量更大（P  = 0.027），当补充物中DDG的量较少时，粪便中N的排泄量则相反（P  = 0.027） ）。DDG水平的增加不会影响瘤胃微生物蛋白的产量（P  > 0.05）。在添加94.5％的DDG时，尽管营养摄入量，总可消化的养分和氮的使用量减少了，但在多种补充物中用多达94.5％的DDG代替玉米和尿素对微生物合成没有不利影响。