Thermographic assessment of hoof temperature in dairy cows with different mobility scores

The aim of this study was to determine if temperature varies in hooves of cows with different mobility scores (MS) using infrared thermography. A total of 120 Friesian, Kiwi cross and Jersey cows were used, which were grouped according to their mobility scores (MS 0-3: n=30 in each MS group). Animals were introduced in a crush for clinical examination and then thermograms from the anterior, posterior, lateral and sole views were taken. Thermogram analysis of different anatomical hoof zones was performed. The temperatures obtained for different views were: anterior (20.8 °C-24.7 °C), posterior (20.7 °C-25.9 °C), lateral (19.2 °C-22.4 °C) and sole (16.5 °C-20.1 °C). The observed zonal temperature for each view was independent and similar for all MS, however significant differences between cows with MS 0 and MS 3 are described. For this purpose, a threshold temperature for the sole view>16.6 °C was set allowing the identification of 83% cows with MS 1 and 60% those cows with MS 0. The best trade off was obtained for the posterior view, with a threshold temperature>23.5 °C, allowing the identification ~70% of both cows with MS 0 and MS 3. Using IRT we were able to show that cows with MS 3 had higher hoof temperatures compared to cows with MS 0 in the anterior, posterior and sole views. None of the evaluated thermographic views showed significant temperatures changes for cows with MS 1 and MS 2. IRT is not a practical method to be used on farm and does not contribute to early lameness detection.