Thermal imaging: A potential tool for early detection of tail lesions in pigs?

Tail biting in pigs is a serious problem both from an animal welfare and an economic perspective. Once the behaviour starts, it is important to identify it and intervene immediately to restrict the spread and risk of secondary problems, such as infections. In this study, we tested whether thermal camera imaging could be used as an aid for early detection of tail biting. We also assessed links between skin temperature, tail health and saliva biomarkers for stress and inflammation. Bitten tails were slightly warmer based on thermal imaging than non-lesioned tails. However, the difference was not sufficiently large or specific to enable its use as a practical tool in the early detection of tail lesions. The methodology, however, warrants further investigation. Shortened, but healed tails had a lower skin temperature than tails of other health categories. In combination with a lower saliva cortisol level in pigs with shortened tails, potentially indicative of chronic stress, this supports previous studies indicating chronic pain in shortened pig tails, and/or chronic stress as a result of being a victim of tail biting. These findings provide a further insight into the link between stress, infections and tail biting, while also illustrating potential for skin temperature changes to be used as an early indicator of health and welfare challenges in pigs.