摘要
Sixty crossbred beef steers (initial BW = 412 kg) were used in a 83-d finishing study to determine the effect of feeding dry rolled high-oil corn on performance and total-tract digestibility of finishing diets. Steers were allotted by weight to the following dietary treatments: 1) control corn (C; 82% normal corn, 12% triticale silage), 2) high-oil corn (HO; 82% high-oil corn, 12% silage), and 3) high-oil corn formulated to be isocaloric to C (ISO; 74% high-oil corn, 20% silage). Total lipid content was 4.9% (DM basis) for normal corn and 7.0% for high-oil corn. Steers were individually fed using electronic gates. Quantity of feed offered and refused was recorded daily. Fecal samples were collected on d 63 to 66 of the trial to determine digestibility. Chromic oxide was fed as an indigestible marker for 7 d before fecal collection began. Planned contrasts of HO vs C and ISO vs C were used to assess treatment differences. Dry matter intake was greater for steers fed C vs HO (P < 0.01) or C vs ISO (P < 0.01), but daily gain and feed efficiency were not affected (P > 0.05) by treatments. Digestibility of DM, OM, starch, and GE was greater (P < 0.05) for the HO diet than the C diet, but lipid digestibility did not differ among treatments (P > 0.05). The combined effect of greater GE content and digestibility resulted in greater (P < 0.01) DE content for the HO than for the C diet. Calculated DE of the corn was 8.3% greater (3.74 Mcal/kg; P < 0.01) for the HO diet and 6.5% greater (3.67 Mcal/kg; P < 0.01) for the ISO diet than the corn in the C diet (3.25 Mcal/kg). Dry matter and GE digestibility did not differ (P > 0.05) between the C and ISO diets. Steers consuming ISO had greater (P < 0.05) starch digestibility than steers fed the C diet. Although HO had higher DE, DE intake was similar (P > 0.05) for HO and C due to lower DMI for HO. These results indicate that available energy is greater from high-oil corn than from typical corn, but depressed voluntary feed intake prevented performance improvements and resulted in equal energy intakes between high-oil corn and typical corn diets.
摘要译文
在一项为期83天的精加工研究中，使用纯种牛肉阉牛（初始体重\x3d 412公斤），以确定饲喂干轧高油玉米对完成日粮的性能和全消化道消化率的影响。对以下饮食处理按重量分配阉牛：1）对照玉米（C; 82％普通玉米，12％黑小麦青贮饲料），2）高油玉米（HO; 82％高油玉米，12％青贮饲料），和3）配制成与C等热的高油玉米（ISO; 74％高油玉米，20％青贮）。正常玉米的总脂质含量为4.9％（DM基准），高油玉米的总脂质含量为7.0％。使用电子门单独喂食转向器。每天记录提供和拒绝的饲料数量。在试验的第63-66天收集粪便样品以确定消化率。粪便收集开始前，将氧化铬作为难消化的标记物饲喂7天。 HO与C和ISO与C的计划对比用于评估治疗差异。饲喂C对HO（P 0.01）或C对ISO（P 0.01）的干物质摄入量较大，但处理对日增重和饲料效率没有影响（P 0.05）。 DM，OM，淀粉的消化率，而GE饮食比C饮食更高（P 0.05），但脂肪消化率在各治疗组间没有差异（P 0.05）。更高的GE含量和消化率的综合效应导致HO的更高（P 0.01）DE含量比C饮食。玉米的计算DE值增加了8.3％（3.74 Mcal / kg; P 0。01），对于ISO饮食，比C饮食中的玉米（3.25 Mcal / kg）高6.5％（3.67 Mcal / kg; P 0.01）。干物质和GE消化率没有差异（P 0。05）C和ISO饮食之间。消耗ISO的阉牛比喂食C饮食的阉牛具有更高的（P 0.05）淀粉消化率。尽管HO具有较高的DE，但DE摄入量相似（P 0。05）因为HO的较低DMI而导致HO和C。这些结果表明，高油玉米的可用能量高于典型玉米，但抑制自愿采食量妨碍了性能的提高，并导致高油玉米和典型玉米日粮之间能量摄入量相等。
J. G. Andrae;C. W. Hunt;S. K. Duckett;L. R. Kennington;P. Feng;F. N. Owens;S. Soderlund. Effect of high-oil corn on growth performance, diet digestibility, and energy content of finishing diets fed to beef cattle[J]. Journal of Animal Science, 2000,78(9): 2257–2262