2026-09-18T19:17:07Zhttps://digital.library.adelaide.edu.au/server/oai/request

oai:digital.library.adelaide.edu.au:2440/1342942026-06-12T07:42:58Zcom_2440_14759col_2440_14760

Pitchford, Wayne Wilkes, Michael McGilchrist, Peter Preston, Farrah Louise School of Animal and Veterinary Sciences 2021 https://hdl.handle.net/2440/134294 Australian beef is renowned the world over for its high quality and safe production in a clean, green environment. One of the greatest contributors restricting the supply of quality product is dark cutting beef. While this quality defect has been the centre of much research, there is a comparatively small understanding of the importance of lairage factors and their impact on this problem. Given time spent in lairage is an inevitable component of beef production, the aim of this project was to understand the role of pre-slaughter factors, specifically dark cutting and pre-slaughter hide washing practices. This work, conducted at one large southern Australian processor, included an observational cohort study of 3,054 cattle and historical data analysis using 2,929 records. A literature review identified a paucity of information on pre-slaughter hide washing, a common practice in Australian abattoirs where live animals are cleaned to remove mud, faeces and bedding from the hide. Australian and International Standards require cattle to be washed prior to slaughter to ensure they are in a clean condition for processing. However, the effectiveness of this procedure at controlling hide and carcase microbial contamination is questionable. Additionally, it has been shown to negatively affect meat quality and may adversely affect welfare. Lairage factors affecting dark cutting incidence and animal behaviour were identified and spanned from the time of unloading until the point of slaughter. Behaviours observed during unloading (jumping, mounting, exit score, unloading time, number of stock on truck) and in lairage (head down) were associated with an increase of up to 18.5% and 0.3%, respectively, in dark cutting incidence. Pre-slaughter hide washing was also associated with an increase in dark cutting incidence of 5.5% for each additional wash animals received while in lairage pens. The time of day, and number and duration of washes with a high-pressure hose also had a significant effect on behaviour. A more targeted study described the change in behaviour resulting from washing, including an increase in behaviours indicative of stress and a decrease in resting behaviours. Beef carcase hygiene records were used to identify periods of risk for increased microbial contamination to guide future work. Current pre-slaughter hide washing practices lack scientific grounding, contribute to increased dark cutting, and change animal behaviour. A recommendation is given for future work to investigate washing with a multi-factorial approach, ensuring beef quality while maintaining safety and animal welfare throughout production. Thesis (Ph.D.) -- University of Adelaide, School of Animal and Veterinary Sciences, 2021 en pre-slaughter hide washing dark cutting beef animal behaviour and welfare carcase hygiene Improving beef quality through pre-slaughter cattle management Thesis This electronic version is made publicly available by the University of Adelaide in accordance with its open access policy for student theses. Copyright in this thesis remains with the author. This thesis may incorporate third party material which has been used by the author pursuant to Fair Dealing exceptions. If you are the owner of any included third party copyright material you wish to be removed from this electronic version, please complete the take down form located at: http://www.adelaide.edu.au/legalsopen.access