The influence of bedding on the time horses spend recumbent

To determine if bedding has any influence on the time horses spend recumbent, 8 horses kept on straw and 8 kept on wood shavings were observed from 10:00 PM to 5:30 AM for two successive nights. Observations were conducted using time-lapse video recordings. Lying down and rising behavior, as well as frequency and duration of bouts spent in lateral and sternal recumbency, was registered. The results showed that horses on straw were lying in lateral recumbency three times longer than horses on shavings (P < .001), whereas the time horses spent in sternal recumbency did not differ. The longest period of noninterrupted lateral recumbency was longer for horses on straw than for those on shavings. Because horses must lie down, preferably in lateral recumbency, to achieve paradoxical sleep, the reduced time spent in lateral recumbency in horses on wood shavings may affect their welfare and performance. Independent of the bedding, we further observed that, as the horses got up from recumbency, most of them made attempts to roll over before rising. This behavior appeared to be caused by some difficulty in rising, possibly due to the box size, and might have a connection with the fact that horses sometimes get stuck against the box wall.