McKenna D R, Roebert D L, Bates P K, Schmidt T B, Hale D S, Griffin D B, Savell J W, Brooks J C, Morgan J B, Montgomery T H, Belk K E, Smith G C
Texas Agricultural Experiment Station, Department of Animal Science, Texas A&M University, College Station 77843-2471, USA.
J Anim Sci. 2002 May;80(5):1212-22. doi: 10.2527/2002.8051212x.
The National Beef Quality Audit-2000 was conducted to assess the current status ofthe quality and consistency of U.S. fed steers and heifers. Between May and November 2000, survey teams assessed hide condition (n = 43,415 cattle for color, brands, mud/manure), bruises (n = 43,595 carcasses), offal and carcass condemnation (n = 8,588 cattle), and carcass quality and yield information (n = 9,396 carcasses) in 30 U.S. beef packing plants. Hide colors were black (45.1%), red (31.0%), yellow (8.0%), Holstein (5.7%), gray (4.0%), white (3.2%), brown (1.7%), and brindle (1.3%). Brand frequencies were no (49.3%), one (46.2%), and two or more (4.4%), and brands were located on the butt (36.3%), side (13.7%), and shoulder (3.6%). Most cattle had no (18.0%) or a small amount (55.8%) of mud/manure on their hides, and they had no (77.3%) horns. Most carcasses (53.3%) were not bruised, 30.9% had one bruise, and 15.8% had multiple bruises. Bruise location and incidence were round (14.9%), loin (25.9%), rib (19.4%), chuck (28.2%), and brisket, flank, and plate (11.6%). Condemnation item and incidence were liver (30.3%), lungs (13.8%), tripe (11.6%), heads (6.2%), tongues (7.0%), and carcasses (0.1%). Carcass evaluation revealed these traits and frequencies: steer (67.9%), heifer (31.8%), and bullock (0.3%) sex-classes; dark-cutters (2.3%); A (96.6%), B (2.5%), and C or older (0.9%) overall maturities; and native (90.1%), dairy-type (6.9%), and Bos indicus (3.0%) breed-types. Mean USDA yield grade traits were USDA yield grade (3.0), carcass weight (356.9 kg), adjusted fat thickness (1.2 cm), longissimus muscle area (84.5 cm2), and kidney, pelvic, and heart fat (2.4%). USDA yield grades were Yield Grade 1 (12.2%), Yield Grade 2 (37.4%), Yield Grade 3 (38.6%), Yield Grade 4 (10.4%), and Yield Grade 5 (1.3%). Mean USDA quality grade traits were USDA quality grade (Select85), marbling score (Small23), overall maturity (A66), lean maturity (A65), and skeletal maturity (A67). Marbling score distribution was Slightly Abundant or higher (2.3%), Moderate (4.8%), Modest (13.1%), Small (33.3%), Slight (43.3%), and Traces (3.4%). USDA quality grades were Prime (2.0%), Choice (49.1%), Select (42.3%), Standard (5.6%), and Commercial, Utility, Cutter, and Canner (0.9%). This information will help the beef industry measure progress compared to the past two surveys and will provide a benchmark for future educational and research activities.
2000年开展了全国牛肉质量审计，以评估美国育肥牛和育成母牛的质量现状及一致性。2000年5月至11月期间，调查团队在美国30家牛肉包装厂评估了牛皮状况（n = 43415头牛，评估颜色、烙印、泥浆/粪便）、瘀伤情况（n = 43595头牛胴体）、内脏和胴体废弃情况（n = 8588头牛）以及胴体质量和产量信息（n = 9396头牛胴体）。牛皮颜色为黑色（45.1%）、红色（31.0%）、黄色（8.0%）、荷斯坦花色（5.7%）、灰色（4.0%）、白色（3.2%）、棕色（1.7%）和斑纹色（1.3%）。烙印频率为无烙印（49.3%）、一个烙印（46.2%）以及两个或更多烙印（4.4%），烙印位于臀部（36.3%）、侧面（13.7%）和肩部（3.6%）。大多数牛的牛皮上没有（18.0%）或只有少量（55.8%）泥浆/粪便，并且没有角（77.3%）。大多数牛胴体（53.3%）没有瘀伤，30.9%有一处瘀伤，15.8%有多处瘀伤。瘀伤部位及发生率分别为圆形部位（14.9%）、腰部（25.9%）、肋部（19.4%）、肩胛部（28.2%）以及胸部、腹部和肋腹部位（11.6%）。废弃项目及发生率分别为肝脏（30.3%）、肺脏（13.8%）、牛肚（11.6%）、头部（6.2%）、舌头（7.0%）和胴体（0.1%）。胴体评估显示了以下特征及频率：阉牛（67.9%）、育成母牛（31.8%）和小公牛（0.3%）的性别类别；暗切牛肉（2.3%）；总体成熟度为A（96.6%）、B（2.5%）以及C级或更老（0.9%）；品种类型为本地牛（90.1%）、乳用型（6.9%）和印度瘤牛（3.0%）。美国农业部胴体产量等级的平均特征为：美国农业部胴体产量等级（3.0）、胴体重（356.9千克）、调整后的脂肪厚度（1.2厘米）、背最长肌面积（84.5平方厘米）以及肾、骨盆和心脏脂肪含量（2.4%）。美国农业部胴体产量等级为1级（12.2%）、2级（37.4%）、3级（38.6%）、4级（10.4%）和5级（1.3%）。美国农业部质量等级的平均特征为：美国农业部质量等级（精选85）、大理石花纹评分（少量23）、总体成熟度（A66）、瘦肉成熟度（A65）和骨骼成熟度（A67）。大理石花纹评分分布为丰富或更高（2.3%）、适中（4.8%）、适度（13.1%）、少量（33.3%）、轻微（43.3%）和微量（3.4%）。美国农业部质量等级为特优级（2.0%）、一级（49.1%）、精选级（42.3%）、标准级（5.6%）以及商用级、实用级、切割级和罐头级（0.9%）。这些信息将有助于牛肉行业衡量与过去两次调查相比的进展情况，并为未来的教育和研究活动提供一个基准。
