Precision livestock farming has emerged with the aim of providing detailed information to detect and reduce problems related to animal management. This study aimed to develop and validate computer vision techniques to track required features of cattle face and to remotely assess eye temperature, ear-base temperature, respiration rate, and heart rate in cattle. Ten dairy cows were recorded during six handling procedures across two consecutive days using thermal infrared cameras and RGB (red, green, blue) video cameras. Simultaneously, core body temperature, respiration rate and heart rate were measured using more conventional ‘invasive’ methods to be compared with the data obtained with the proposed algorithms. The feature tracking algorithm, developed to improve image processing, showed an accuracy between 92% and 95% when tracking different areas of the face of cows. The results of this study also show correlation coefficients up to 0.99 between temperature measures obtained invasively and those obtained remotely, with the highest values achieved when the analysis was performed within individual cows. In the case of respiration rate, a positive correlation (r = 0.87) was found between visual observations and the analysis of non-radiometric infrared videos. Low to high correlation coefficients were found between the heart rates (0.09–0.99) obtained from attached monitors and from the proposed method. Furthermore, camera location and the area analysed appear to have a relevant impact on the performance of the proposed techniques. This study shows positive outcomes from the proposed computer vision techniques when measuring physiological parameters. Further research is needed to automate and improve these techniques to measure physiological changes in farm animals considering their individual characteristics.

Respiratory diseases are a major problem in the pig industry worldwide. Due to the impact of these diseases, the early identification of infected herds is essential. Computer vision technology, using RGB (red, green and blue) and thermal infrared imagery, can assist the early detection of changes in animal physiology related to these and other diseases. This pilot study aimed to identify whether these techniques are a useful tool to detect early changes of eye and ear-base temperature, heart rate and respiration rate in pigs that were challenged with Actinobacillus pleuropneumoniae. Clinical observations and imagery were analysed, comparing data obtained from animals that showed some signs of illness with data from animals that showed no signs of ill health. Highly significant differences (p < 0.05) were observed between sick and healthy pigs in heart rate, eye and ear temperature, with higher heart rate and higher temperatures in sick pigs. The largest change in temperature and heart rate remotely measured was observed around 4–6 h before signs of clinical illness were observed by the skilled technicians. These data suggest that computer vision techniques could be a useful tool to detect indicators of disease before the symptoms can be observed by stock people, assisting the early detection and control of respiratory diseases in pigs, promoting further research to study the capability and possible uses of this technology for on farm monitoring and management.

Surface temperature recording has shown promise in older pigs and in piglets but only under controlled conditions. The aim of this experiment was to compare surface temperatures using an infrared thermal camera (pointer), verified by the maximum temperature from the thermal images extracted by an algorithm (MATLAB®R2020), at the base, tip of ear, or eye, with rectal temperature under production conditions. The influence of bodyweight (BWC1; ≤0.80 kg, BWC2; 0.81 kg to 1.10 kg and BWC3; >1.10 kg), time post-partum (0 and 24 h) and colostrum intake (CI1; <200 g and CI2, ≥200 g) were investigated. Ear tip pointer temperatures showed low correlations with rectal temperature (r < 0.39; P = 0.20). Both the ear base and eye had moderate correlations (r = 0.53 and 0.55, respectively; P < 0.001 for both) to rectal temperature, and high correlations between pointer and extracted values (r = 0.73 and 0.82, respectively; P < 0.001 for both). At birth, eye temperatures had a moderate correlation with rectal temperature. The extracted eye, but not rectal or ear base, temperatures were higher (P = 0.01) in piglets consuming greater amounts of colostrum. In contrast to research settings, production conditions are highly variable and increase the inaccuracy of the surface temperature recordings. Therefore, overall, surface temperatures were not appropriate for commercial application in neonatal piglets.