摘要
In four feeding trials with beef steers, corn silage (CS), alfalfa hay (AH), and alfalfa silage (AS) were compared as roughage sources in dry-rolled (DRC); dry whole (DWC); ground, high-moisture (GHMC); and whole, high-moisture com (WHMC) fattening diets. In processed corn diets (DRC and GHMC), steers fed CS had lower DMI (P < .05) and feed:gain ratios (P < .10) than steers fed AS as the roughage source. In a separate trial, greater gains (P < .10) and lower feed:gain ratios (P < .05) were found during the initial feeding period, which included the adaptation phase, for steers fed CS vs steers fed AH as the roughage source. Over the entire feeding period, lower (corn type × roughage source interaction, P < .05) feed:gain ratios were found in GHMC diets when CS was fed as the roughage source; feed:gain ratios were similar in steers fed DRC diets containing either CS or AH. Over the entire feeding period, similar performance was found among steers fed the various roughage sources in DWC diets; however, with WHMC diets, steers fed AS as the roughage source had lower feed:gain ratios than did steers fed AH (P < .05) or CS (P > .10). In the processed corn diets, high correlations were found between diet NDF digestibility and gain (r = .80), intake (r = .68), and feed:gain ratios (r = −.66); similar trends were found in WHMC diets but not in DWC diets. These results suggest that the ideal roughage source to complement finishing diets may depend on com processing method and feeding period (adaptation vs finishing).
摘要译文
在四个饲养牛试验的试验中，玉米青贮饲料（CS），苜蓿干草（AH）和苜蓿青贮饲料（AS）在干轧（DRC）中作为粗饲料来源进行比较。干整（DWC）;地面，高水分（GHMC）;和全面的高水分玉米（WHMC）增肥饮食。在加工过的玉米日粮（DRC和GHMC）中，饲喂CS的阉牛的DMI较低（P 0.05）和饲料：增益比（P 。10）比饲喂AS的阉牛作为粗饲料来源。在另一项试验中，在最初的饲喂期间发现更大的增加（P .10）和更低的饲料：增益比（P .05）其中包括适应阶段，阉牛喂养CS与阉牛喂养AH作为粗饲料来源。在整个饲养期间，较低（玉米型×粗饲料源相互作用，P 。05）饲料：当饲喂CS作为粗饲料时，在GHMC饲料中发现增重比率;饲料：在含有CS或AH的DRC日粮中，阉牛的增重比例相似。在整个喂养期间，DWC饮食中饲喂各种粗饲料的阉牛之间发现类似的表现;然而，在WHMC饮食中，与饲喂AH的阉牛相比（P 0.05）或CS（P .10），饲喂AS的阉牛的粗饲料比饲料：增重率低。在加工过的玉米日粮中，饮食NDF消化率与增重（r \x3d .80），摄入量（r \x3d .68）和饲料：增重比（r \x3d -.66）之间存在高度相关性。在WHMC饮食中发现类似趋势，但在DWC饮食中未发现类似趋势。这些结果表明理想的粗饲料来源补充完成日粮可能取决于玉米加工方法和饲养期（适应VS整理）。
T. L. Mader;J. M. Dahlquist;L. D. Schmidt. Roughage sources in beef cattle finishing diets[J]. Journal of Animal Science, 1991,69(2): 462–471