Diurnal and day-to-day movement patterns of finishing pigs on deep straw bedding during the last 20 d before slaughter

Monitoring movement patterns of pigs provides valuable insight into welfare, health, and adaptation to housing environments, yet individual- and time-resolved evidence from deep-straw systems is limited. We monitored 16 finishing pigs housed on deep straw bedding during the last 20 d before slaughter using an RFID (radio-frequency identification)-LoRaWAN (Long Range Wide Area Network) system. One-Hz detections were converted to estimated distance from the receiver and aggregated to hourly movement (cm·h-1). In total, 7,680 pig×day×hour records were possible (16 pigs × 20 d × 24 h); hours without valid positioning data were excluded, resulting in 6,026 records for inferential analyses. Hourly movement was analyzed using a linear mixed model with fixed effects of hour, day, and their interaction, a random intercept for pig, and an AR(1) residual structure. Pigs exhibited a clear diurnal rhythm with movement lowest during the night and peaking between midday and afternoon. Movement differed among days, and the day × hour interaction showed day-specific modulation of the diurnal profile. Between-pig differences were substantial (ICC ≈ 0.29), supporting the use of individual baselines for precision monitoring. Environmental covariates (temperature, relative humidity, PM2.5) were not associated with movement in the day-by-timeline model. These results highlight the value of hour-aware and individualized approaches when using movement data for precision livestock farming applications in enriched housing.