Long-Term Measurement of Piglet Activity Using Passive Infrared Detectors

Abstract

Measuring animal activity is useful for monitoring animal welfare in real time. In this regard, passive infrared detectors have been used in recent years to quantify piglet activity because of their robustness and ease of use. This study was conducted on a commercial farm in Northwest Spain during six complete breeding cycles. The hourly average activity of weaned piglets with a body mass of 6–20 kg was recorded and further analyzed by using a multiplicative decomposition of the series followed by a wavelet analysis. Finally, the real series were compared to the theoretical models of activity. Results showed a high level of movement immediately after weaning and a sustained level of activity throughout the cycles. The daily behavior of the piglets followed a clear circadian pattern with several peaks of activity. No differences in behavior were observed between spring–summer cycles and autumn–winter cycles. Single-peak models achieved the best predictive results. In addition, the installed sensors were found to underestimate mild activity.

Modelling of Animal Activity, Illuminance, and Noise on a Weaned Piglet Farm

“…Thus, cosine models can be a useful tool to study and predict these variables. Whereas other authors presented models with up to four daily peaks [13], in this research, animal behaviour shows a pattern with two daily peaks [8,12,14,15], coinciding with human activity inside the building, with a preference for inactivity when there is less light [2,55] and around midday [12,14]. These two peaks occur after the distribution of feed (08:00 h, 12:00 h and 16:00 h), which may be the cause for such peaks, in agreement with the evolution of the third harmonic.…”

“…In fact, there are substantial differences in the amount of activity of pigs between daytime and night-time, and their patterns of activity show variations depending on the time of day and the stage of growth [13]. Daily activity generally fits models with two peaks [8,12,14,15], although single-peak models have also been found during the first weeks postweaning [14] or in buildings with natural ventilation [12]. In other studies, daily activity has shown four daily peaks [13].…”

“…The behaviour of pigs is highly influenced by the environment in the building [1], although it is also affected by other parameters, such as gas concentration, illuminance, noise, or health problems [2][3][4][5][6][7]. Animal activity is an important indicator of welfare that is especially relevant in intensive systems [8] because it is an early gauge for behavioural changes [9] that are caused by poor environmental conditions in the building or by health issues, among others [1,5,[9][10][11]. Therefore, measuring animal activity can provide key data to reduce deficiencies in animal welfare, thus improving production efficiency and enabling sustainable pig farming [9].…”

“…Various methods have been used to measure animal activity, among which are microphones [39,44], sensors attached to the animals [45,46], analysis of video footage [47] and other low-cost practices like passive infrared detectors (PID) [8,14]. These methods for monitoring and analysing animal behaviour are widely used to quantify levels of animal activity, albeit with the disadvantage of not allowing for individual observation of animals housed in groups.…”

Computer Vision-Based Measurement Techniques for Livestock Body Dimension and Weight: A Review

“…In recent years, the use of intelligent sensing devices for data collection has emerged as a promising solution to mitigate the problems associated with manual data collection. For instance, deploying devices like infrared sensors [18][19][20], 3D point cloud cameras [21,22], and RGB cameras [23,24] in farming or animal research settings facilitates the capture of livestock images and 3D coordinate points on their surfaces. Subsequently, employing 3D reconstruction techniques generates complete 3D models of livestock.…”