THERMOREGULATORY BEHAVIOR OF SHEEP HOUSED IN INSULATED AND UNINSULATED BUILDINGS

The objective of this study was to investigate the thermoregulatory behaviour of sheep in confinement. In Experiment 1, two groups of 8 lambs in both an insulated (IN) and uninsulated (UN) house (total 32 animals) were studied; the durations of lying with and without body contact and standing were recorded (24 h time-lapse video recording) for five selected days before and after shearing (40 24-h periods). Before shearing the lying time was significantly longer in IN than UN (917.2 min day-1 and 862.1 min day-1 respectively). The first day after shearing the lying time was reduced by 39%, but approached the level before shearing around 25 days later. There was no difference between IN and UN. In Experiment 2, the body and head posture and the number of physical contacts (huddling) when lying was recorded at noon every day. Around 90% of the sheep before shearing were lying with all legs hidden under the body, and there was no difference between IN and UN. Huddling was more pronounced in UN. In Experiment 3, a group of 12 lambs could choose between two pens (Pen A with wooden slatted floor and Pen B with an expanded metal floor). Before shearing the lambs showed no preference. The first day after shearing the lambs did not lie down at all, and later they almost exclusively preferred to lie at the wooden slats. This study shows that the main thermoregulatory strategy for sheep exposed to low temperatures, especially after shearing, is to reduce the lying time. Huddling was exploited to some extent, but the results showed that the sheep did not utilize the strategy of changing lying posture and time of day for lying. © 1990.