Case Study: Tympanic Temperature and Behavior Associated with Moving Feedlot Cattle1

Body temperature is often used as an indicator of animal health status. In a series of handling experiments, tympanic temperatures (TT) were obtained in unrestrained feedlot cattle. In a January experiment (BW = 531 ± 54 kg), TT were increased (P<0.05) 0.65°C and 0.58°C by moving cattle 600 m in morning and afternoon, respectively. Moving cattle (BW = 456 ± 67 kg) 150 and 600 m in August elevated TT by 0.30°C and 0.67°C, respectively. Moving cattle (BW = 415 ± 62 kg) 900 m in June elevated (P<0.05) TT by 0.78°C. Recovery TT was determined to be the time peak TT declined to levels equal to or below control (non-moved cattle) TT. Recovery times averaged 3.5 h in the winter, but ranged from <1 h to approximately 2 h in the spring and summer experiments. Moving cattle decreased (P<0.05) feed intake by approximately 1 kg/d for up to 48 h after moving was completed. Moving cattle in the morning also decreased (P<0.05) the number of animals resting in the afternoon (1400 h; Experiment 3) and increased (P<0.05) the number of animals panting throughout the day (1100 and 1400 h; Experiment 4). Effects of cattle movement on body temperature may need to be taken into account when evaluating animal health status. Conclusions based on these data would be most applicable for feedlot cattle exposed to warm and thermoneutral environmental conditions.