Depenbusch B E, Drouillard J S, Loe E R, Higgins J J, Corrigan M E, Quinn M J
Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506, USA.
J Anim Sci. 2008 Sep;86(9):2270-6. doi: 10.2527/jas.2007-0017. Epub 2008 May 9.
Three hundred seventy-one crossbred-yearling heifers (299 +/- 9 kg initial BW) were obtained from a common source and used in a randomized complete-block designed finishing study. A 2 x 3 factorial arrangement of treatments was used with one factor being diet: based on steam-flaked corn finishing diet (SFC) or SFC plus 25% (dry basis) corn wet distillers grains with solubles (WDGS). The second factor was feed additives: no added antibiotics (NONE), 300 mg of monensin daily (MONENSIN), or 300 mg of monensin + 90 mg of tylosin daily (MON+TYL). Main effect of diet resulted in no difference in DMI (P = 0.34). Heifers fed SFC gained 9% faster (P = 0.01) and were 7% more efficient (P = 0.01) than heifers fed WDGS. In addition, heifers fed SFC had 3% heavier (P = 0.01) HCW; 1% greater (P = 0.01) dress yield; and had 3% larger (P = 0.05) LM area. Marbling score and carcasses that graded USDA Choice or better were both greater (P </= 0.03) for heifers fed SFC. Heifers fed MONENSIN had a smaller (P = 0.01) LM area than heifers fed NONE and tended (P = 0.09) to have smaller LM area than heifers fed MON+TYL. Marbling score, USDA quality grade, and USDA yield grade were not different (P >/= 0.12) among feed additive treatments. Kidney, pelvic, and heart fat and s.c. fat thickness at the 12th rib were also not different (P >/= 0.55) for main effects of diet and feed additive. There was a tendency (P = 0.09) for a diet x feed additive interaction for the most severe (A+) liver abscesses. Heifers fed NONE yielded the greatest percentage (16%) of A+ livers in the SFC treatment, whereas heifers fed MON+TYL yielded the greatest percentage (10%) in the WDGS treatment. Including wet distillers grains with solubles in diets based on steam-flaked corn decreased finishing heifer performance, HCW, and marbling. Tylosin addition tended to decrease severity of liver abscesses in diets containing SFC, but not in diets containing WDGS. These data indicate that monensin and tylosin may not be as effective when used in steam-flaked corn diets with 25% WDGS.
从同一来源获取了371头杂交一岁小母牛（初始体重299±9千克），用于一项随机完全区组设计的育肥研究。采用2×3析因处理安排，其中一个因素是日粮：基于蒸汽压片玉米育肥日粮（SFC）或SFC加25%（干基）玉米湿酒糟及其可溶物（WDGS）。第二个因素是饲料添加剂：不添加抗生素（无）、每日添加300毫克莫能菌素（莫能菌素）或每日添加300毫克莫能菌素+90毫克泰乐菌素（莫能菌素+泰乐菌素）。日粮的主效应导致干物质采食量无差异（P=0.34）。饲喂SFC的小母牛增重速度比饲喂WDGS的小母牛快9%（P=0.01），效率高7%（P=0.01）。此外，饲喂SFC的小母牛热胴体重重3%（P=0.01）；屠宰率高1%（P=0.01）；眼肌面积大3%（P=0.05）。饲喂SFC的小母牛大理石花纹评分以及评为美国农业部精选级或更高等级的胴体比例均更高（P≤0.03）。饲喂莫能菌素的小母牛眼肌面积比饲喂无添加剂的小母牛小（P=0.01），且比饲喂莫能菌素+泰乐菌素的小母牛眼肌面积有变小的趋势（P=0.09）。饲料添加剂处理之间的大理石花纹评分、美国农业部质量等级和美国农业部产量等级无差异（P≥0.12）。日粮和饲料添加剂主效应的肾脏、盆腔和心脏脂肪以及第12肋处的皮下脂肪厚度也无差异（P≥0.55）。对于最严重的（A+）肝脓肿，存在日粮×饲料添加剂交互作用的趋势（P=0.09）。在SFC处理中，饲喂无添加剂的小母牛A+肝脏的比例最高（16%），而在WDGS处理中，饲喂莫能菌素+泰乐菌素的小母牛A+肝脏的比例最高（10%）。在基于蒸汽压片玉米的日粮中添加玉米湿酒糟及其可溶物会降低育肥小母牛的性能、热胴体重和大理石花纹。添加泰乐菌素倾向于降低含SFC日粮中肝脓肿的严重程度，但在含WDGS的日粮中则不然。这些数据表明，当在含有25%WDGS的蒸汽压片玉米日粮中使用时，莫能菌素和泰乐菌素可能效果不佳。
