Written by: Heather Clemenceau
A new study, published January in Frontiers in Veterinary Science, has found that digital thermography can be used in the detection of ante-mortem injuries sustained by horses en route to slaughter. While digital thermography (DT) itself is not a “new” technology, (it has been previously used in the detection of lameness in horses); the authors of the study used DT to assess bruising by identifying areas of the body where there were elevated skin temperatures (consistent with non-visible injuries). The high predictive rates for detecting unseen injuries means that CFIA inspectors or other welfare assessors could use DT as a diagnostic tool to identify injured horses up arrival at slaughterhouses. The obvious relevance of DT here is that it could be used to assign responsibility for transportation injuries to the appropriate offenders – not just for horses, but for other species of animals transported to slaughter as well.
Full text of the study found here.
2019 Roy, Riley, Stryhn, Dohoo and Cockram – Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE., Canada, and the School of Veterinary Sciences, Massey University, Palmerston North, New Zealand
“The transport of horses for slaughter and related management practices may cause externally visible and non-visible injuries due to trauma including fractures, swelling, excoriations, and bruising. The welfare assessments of livestock undertaken following transport to slaughter plants include visual/clinical evaluations by plant personnel or official inspectors. However, horses may have non-visible injuries unrecognized until post-mortem carcass examination. The lack of suitable methods to identify bruised horses ante-mortem limits the ability to differentiate injuries occurring during transport, from those that occur at the slaughter plant itself. It is important to determine which stage of the process is responsible for bruising, so that appropriately directed measures are taken to reduce this risk. Reliable and objective tools to detect non-visible injuries in horses following transport could empower regulatory authorities and plant operators to improve animal transport welfare.
Digital thermography (DT) is a non-invasive imaging technique that records superficial infrared emission patterns. When tissue is damaged, localized hypo- or hyper-perfusion due to vascular injury and inflammation occurs that may be detectable by DT. In horses, DT has been used to detect musculoskeletal and neuromuscular injuries, and to monitor skin lesions. It also has been used for the ante mortem and post mortem detection of blunt force trauma in humans. The authors hypothesized that a qualitative methodology using DT imaging implemented at slaughter plants may identify horses with bruising ante-mortem after transport. The objective of this study was to estimate the sensitivity and specificity of DT images as a diagnostic test for detecting bruising ante-mortem when compared to post-mortem visual examination of carcasses.”
Far too often we have seen the devastating, often fatal, effects of horses transported to slaughter plants in Canada with few individuals ever held accountable. While we collectively work to get horse slaughter shut down, digital thermography is one tool that we can insist the CFIA implement in order to improve welfare. Violators who are found to consistently deliver loads of horses with soft tissue injuries should be assessed the same administrative monetary penalties that the CFIA already applies in the case of non-compliance with the Health of Animals Act (HAA) and Health of Animals Regulations (HAR).