Division of Animal Sciences, College of Agriculture, Food and Natural Resources, University of Missouri, Columbia 65201, USA.
J Anim Sci. 2012 Mar;90(3):892-9. doi: 10.2527/jas.2011-4099. Epub 2011 Oct 28.
Continuous culture and in vivo experiments were conducted to measure changes in ruminal fermentation and animal performance when crude glycerol was added to diets. For the continuous culture experiment (n = 6), diets consisted of 4 levels of crude glycerol (0, 5, 10, and 20%) that replaced corn grain. Dry matter and OM digestibility decreased linearly (P < 0.05) when crude glycerol increased in the diet, and no effect (P = 0.20 and 0.65, respectively) was observed for CP and NDF digestibility. Total VFA concentration and ammonia did not change (P > 0.05) due to crude glycerol level. Microbial efficiency increased quadratically (P = 0.012) as crude glycerol increased, whereas microbial N flow did not differ (P = 0.36) among treatments. As crude glycerol increased in the diet, crude glycerol digestibility decreased (P < 0.05). Seventy-two crossbred steer calves (250 ± 2.0 kg) were assigned to 4 treatments: 0, 5, 10, and 20% crude glycerol that replaced corn grain. Animals were fed for a total of 150 d. No differences (P = 0.08) between treatments were measured for DMI. Average daily gain and GF responded quadratically (P < 0.05), with 10% crude glycerol resulting in the greatest values. In the second in vivo experiment, 100 crossbred steer calves (300 ± 2.0 kg) were assigned to 5 treatments: 0, 5, 10, 12.5, or 15% crude glycerol replaced corn grain. Calves were fed for a total of 135 d. No significant differences (P > 0.05) were measured in growth performance. For Exp. 3, one hundred heifer calves (270 ± 2.0 kg) were assigned to 4 treatments: 0, 5, 10, or 20% crude glycerol that replaced hay. No differences (P > 0.05) were measured in animal performance. We concluded that crude glycerol addition to a diet did not negatively affect ruminal fermentation, and addition of up to 20% in concentrate and hay-based diets should not affect performance or carcass characteristics.
连续培养和体内实验用于测量添加粗甘油对瘤胃发酵和动物性能的变化。对于连续培养实验（n = 6），日粮由 4 个粗甘油水平（0、5、10 和 20%）组成，替代玉米谷物。随着日粮中粗甘油的增加，干物质和有机物消化率呈线性下降（P < 0.05），而 CP 和 NDF 消化率没有影响（分别为 P = 0.20 和 0.65）。总 VFA 浓度和氨没有因粗甘油水平而改变（P > 0.05）。随着粗甘油的增加，微生物效率呈二次方增加（P = 0.012），而微生物 N 流量在处理之间没有差异（P = 0.36）。随着日粮中粗甘油的增加，粗甘油消化率降低（P < 0.05）。72 头杂交阉牛（250 ± 2.0 kg）被分配到 4 个处理组：0、5、10 和 20%的粗甘油替代玉米谷物。动物共饲养 150 天。处理组之间的 DMI 没有差异（P = 0.08）。平均日增重和 GF 呈二次方响应（P < 0.05），10%的粗甘油产生最大的值。在第二个体内实验中，100 头杂交阉牛（300 ± 2.0 kg）被分配到 5 个处理组：0、5、10、12.5 或 15%的粗甘油替代玉米谷物。牛共饲养 135 天。生长性能没有显著差异（P > 0.05）。对于实验 3，100 头小母牛（270 ± 2.0 kg）被分配到 4 个处理组：0、5、10 或 20%的粗甘油替代干草。动物性能没有差异（P > 0.05）。我们得出结论，日粮中添加粗甘油不会对瘤胃发酵产生负面影响，在浓缩饲料和干草基日粮中添加高达 20%的粗甘油不应影响性能或胴体特征。
