Use of infrared ocular thermography to assess physiological conditions of pigs prior to slaughter and predict pork quality variation

- IRT is a technique allowing non-invasive, non-contact, real-time measures of body temperature.
- IRT can be used to estimate pre-slaughter well-being status of market pigs and predict pork-quality variation.
- The IRT measurement taken in the ocular region appears to be a reliable indicator of the physiological condition of the pig and predictor of pork quality.

Infrared thermography (IRT) body temperature readings were taken in the ocular region of 258 pigs immediately before slaughter. Levels of lactate were measured in blood taken in the restrainer. Meat quality was assessed in the longissimus dorsi (LD), semimembranosus (SM), and adductor muscles. Ocular IRT (IROT) temperature was correlated with blood lactate levels (r = 0.20; P = 0.001), with pH taken 1 hour postmortem (pH1: r = − 0.18; P = 0.03) and drip loss (r = 0.20; P = 0.02) in the LD muscle, and with pH1 in the SM muscle (r = − 0.20; P = 0.02). Potentially, IROT may be a useful tool to assess the physiological conditions of pigs at slaughter and predict the variation of important meat quality traits. However, the magnitude of the correlations is rather low, so a further development of image capture technique and further studies under more variable preslaughter conditions ensuring a larger pork quality variation are needed.