Department of Animal Science, University of Nebraska, Lincoln 68583-0908, USA.
J Anim Sci. 2012 Dec;90(12):4634-40. doi: 10.2527/jas.2010-3240. Epub 2012 Aug 2.
Wet distillers grains contain approximately 65% moisture. A partially dried product [modified distillers grains plus solubles (MDGS)] contains about 50% moisture. However, both have similar nutrient composition on a dry matter basis. The objective of this study was to investigate the effects of finishing diets varying in concentration of MDGS on marbling attributes, proximate composition, and fatty acid profile of beef. Yearling steers (n = 268) were randomly allotted to 36 pens, which were assigned randomly to 0, 10, 20, 30, 40 and 50% MDGS (DM basis) and fed for 176 d before harvest. The 48-h postmortem marbling score, marbling texture, and marbling distribution were assessed by a USDA grader and 1 ribeye slice (longissimus thoracis) 7 mm thick was collected from each carcass for proximate and fatty acid analyses. Treatments did not significantly alter marbling score or marbling distribution (P ≥ 0.05). United States Department of Agriculture Choice slices had coarser marbling texture when compared with USDA Select. Although dietary treatment affected marbling texture, no consistent pattern was evident. Diets did not influence fat content, moisture, or ash of the ribeye (P ≥ 0.05). For treatments 0, 10, 30, 40 and 50%, there were positive linear relationships between marbling score and fat percentage in the ribeye (P ≤ 0.05), and all slopes were similar (P = 0.45). Feeding MDGS linearly increased stearic, linoelaidic, linoleic, linolenic, PUFA, and n-6 fatty acids. As dietary MDGS increased, linear decreases were observed in all n-7 fatty acids and cubic relationships were detected for the 18:1 trans isomers [trans-6-8-octadecenoic acid (6-8t), elaidic acid (9t), trans-10-octadecenoic acid (10t), and trans vaccenic acid (11t)]. No effects were observed for saturated fatty acids containing 6 to 14 carbons. Feeding MDGS resulted in increased PUFA, trans, and n-6 fatty acids, minimal effects on marbling texture, and no effects on the relationship of marbling to intramuscular fat content relationship.
湿酒糟含有大约 65%的水分。部分干燥的产品[改性酒糟加可溶性物（MDGS）]含有约 50%的水分。然而，在干物质基础上，它们都具有相似的营养成分。本研究的目的是研究在大理石花纹属性、近似成分和脂肪酸谱上变化浓度的育肥日粮对牛肉的影响。育肥牛（n = 268）被随机分配到 36 个围栏中，这些围栏被随机分配到 0、10、20、30、40 和 50%的 MDGS（DM 基础），在收获前育肥 176 天。美国农业部（USDA）分级员评估了 48 小时的死后大理石花纹评分、大理石花纹纹理和大理石花纹分布，并从每个胴体中收集了 1 块 7 毫米厚的 1 肋眼切片，用于进行近似和脂肪酸分析。处理没有显著改变大理石花纹评分或大理石花纹分布（P≥0.05）。美国农业部（USDA）选择切片的大理石花纹纹理比美国农业部（USDA）精选切片的纹理更粗糙。尽管饮食处理影响了大理石花纹纹理，但没有明显的一致模式。日粮对肋眼的脂肪、水分或灰分没有影响（P≥0.05）。对于 0、10、30、40 和 50%的处理，大理石花纹评分与肋眼脂肪百分比之间存在正线性关系（P≤0.05），所有斜率都相似（P=0.45）。饲喂 MDGS 线性增加了硬脂酸、亚油酸、亚麻酸、亚麻酸、多不饱和脂肪酸和 n-6 脂肪酸。随着日粮 MDGS 的增加，所有 n-7 脂肪酸呈线性下降，而 18:1 反式异构体[反式-6-8-十八碳烯酸（6-8t）、反式-9-十八碳烯酸（9t）、反式-10-十八碳烯酸（10t）和反式棉酚酸（11t）]则呈立方关系。对含有 6 到 14 个碳原子的饱和脂肪酸没有观察到影响。饲喂 MDGS 导致多不饱和脂肪酸、反式脂肪酸和 n-6 脂肪酸增加，对大理石花纹纹理的影响最小，对大理石花纹与肌内脂肪含量关系的影响也最小。
