Lee T L, Reinhardt C D, Bartle S J, Vahl C I, Siemens M, Thomson D U
North American Meat Institute, Washington, DC 20036.
Reinhardt Nutrition Consulting, LLC, Katy, TX 77494.
Transl Anim Sci. 2017 Dec 1;1(4):489-497. doi: 10.2527/tas2017.0055. eCollection 2017 Dec.
Cattle injuries can occur during transportation due to vehicle design, transport conditions, and loading or unloading procedures and lead to carcass bruising and economic loss due to decreased carcass value. The objectives of this study were to determine whether a relationship exists between trauma incurred during unloading and prevalence of carcass bruising in finished beef cattle at commercial slaughter facilities and determine related risk factors which contribute to both trauma and carcass bruising. Breed (classified as either Holstein cattle or beef breeds), sex, distance traveled, and trailer type ("fat/feeder combination" vs. "fat" trailer) were considered risk factors which may contribute to traumatic event prevalence. When carcass bruise prevalence within each lot was used as the dependent variable, breed, sex, distance traveled, traumatic event prevalence, ribeye area, fat thickness, yield grade, and average carcass weight were considered potential risk factors. Carcass bruises were categorized by location and size, according to the Harvest Audit Program Carcass Bruise Scoring System. Traumatic events were observed while cattle exited trailers onto the unloading docks, and were categorized by location on the animal. Average traumatic event prevalence per lot was 20.4% (± 1.11%). Average carcass bruise prevalence by lot was 68.2% (± 1.15%). There was an interaction between breed and trailer type when multiple linear regression was used to explore variables contributing to traumatic events observed at unloading ≤ 0.05). Traumatic events were not associated with prevalence of carcass bruising, while average carcass weight and breed were associated with carcass bruising prevalence. Carcass bruising was more prevalent in Holstein cattle than in cattle which were predominantly beef breeds ≤ 0.01). Average carcass weight was negatively associated with carcass bruise prevalence ( ≤ 0.05). The association between traumatic events at unloading and carcass bruising is not significant when multiple variables are considered, indicating that bruising may occur at numerous other points prior to and during the transportation process, including loading and transport, and that other variables can contribute to carcass bruise prevalence. These areas should be explored to determine all potential causes of bruising in beef carcasses, and to help implement prevention practices.
由于车辆设计、运输条件以及装卸程序等原因，牛在运输过程中可能会受伤，进而导致胴体出现瘀伤，并因胴体价值降低而造成经济损失。本研究的目的是确定在商业屠宰场，育肥牛卸载过程中遭受的创伤与胴体瘀伤发生率之间是否存在关联，并确定导致创伤和胴体瘀伤的相关风险因素。品种（分为荷斯坦牛或肉牛品种）、性别、运输距离和拖车类型（“育肥牛/育肥组合”与“育肥”拖车）被视为可能导致创伤事件发生率的风险因素。当将每批胴体的瘀伤发生率作为因变量时，品种、性别、运输距离、创伤事件发生率、眼肌面积、脂肪厚度、产量等级和平均胴体重量被视为潜在风险因素。根据收获审计计划胴体瘀伤评分系统，胴体瘀伤按位置和大小进行分类。在牛从拖车出口到卸载码头时观察创伤事件，并按动物身上的位置进行分类。每批的平均创伤事件发生率为20.4%（±1.11%）。每批胴体的平均瘀伤发生率为68.2%（±1.15%）。当使用多元线性回归来探索导致卸载时观察到的创伤事件的变量时，品种和拖车类型之间存在交互作用（P≤0.05）。创伤事件与胴体瘀伤发生率无关，而平均胴体重量和品种与胴体瘀伤发生率有关。荷斯坦牛的胴体瘀伤比主要为肉牛品种的牛更普遍（P≤0.01）。平均胴体重量与胴体瘀伤发生率呈负相关（P≤0.05）。当考虑多个变量时，卸载时的创伤事件与胴体瘀伤之间的关联不显著，这表明瘀伤可能在运输过程之前和期间的许多其他点发生，包括装载和运输，并且其他变量可能导致胴体瘀伤发生率。应该对这些领域进行探索，以确定牛肉胴体瘀伤的所有潜在原因，并有助于实施预防措施。
