Loudon Kate M W, Tarr Garth, Pethick David W, Lean Ian J, Polkinghorne Rod, Mason Maddison, Dunshea Frank R, Gardner Graham E, McGilchrist Peter
School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
School of Mathematics and Statistics, The University of Sydney, Sydney, NSW 2006, Australia.
Animals (Basel). 2019 Jul 31;9(8):503. doi: 10.3390/ani9080503.
This study considered the relationship between pre-slaughter stressors and plasma biomarkers in 488 pasture-raised cattle across two experiments. The design aimed to test groups consisting of steer only, heifer only, and mixed sex cattle under direct kill versus rested (14 days in abattoir holding paddocks) protocols. In Experiment One, cattle were sourced from four farms, and transported by trucks and ships on the same day. In Experiment Two, cattle were sourced from four farms where a comparison was made between marketing via two commercial saleyards or direct farm gate consignment to abattoir. Blood samples were collected at exsanguination for subsequent analyses and relation to meat quality attributes. Muscle damage, as indicated by creatine kinase, is the biomarker most correlated to ultimate pH and muscle glycogen concentrations. A two-week rest period is effective for lowering this enzyme and improving muscle glycogen concentration. Although the cattle was subjected to a range of stress inducing treatments, we found that plasma biomarkers alone appeared insufficient for use as diagnostic stress indicators.
本研究通过两个实验，对488头牧场饲养的牛的屠宰前应激源与血浆生物标志物之间的关系进行了考量。该设计旨在测试仅含公牛、仅含小母牛以及混合性别的牛组成的组，分别采用直接宰杀与休息（在屠宰场围场休息14天）方案。在实验一中，牛来自四个农场，于同一天通过卡车和轮船运输。在实验二中，牛来自四个农场，对通过两个商业牲畜市场销售或直接从农场大门托运至屠宰场这两种销售方式进行了比较。放血时采集血样，以便后续分析并与肉质属性相关联。肌酸激酶所表明的肌肉损伤，是与最终pH值和肌肉糖原浓度相关性最高的生物标志物。两周的休息期对于降低这种酶并提高肌肉糖原浓度是有效的。尽管这些牛接受了一系列诱导应激的处理，但我们发现仅血浆生物标志物似乎不足以用作诊断应激指标。
