Day-night variations in sleep and locomotor activity in lambs during the first 72 hours after birth and following the onset of rumination
Fig 5
Distribution of vigilance states.
Hypnograms representative of the two recording periods (A and B), presenting the distribution of vigilance states (wakefulness, drowsiness, NREM sleep, REM sleep and rumination) during the recording periods illustrated. The increase in colour density indicates the transition from wakefulness to sleep stages, with the black and white bars corresponding to the dark and light phases of the L/D cycle, respectively. The mean (± SEM) proportion of vigilance states was calculated and averaged over the night and day of each recording period (C and D). Significance levels were set at p < 0.05 (*), p < 0.01 (**), p < 0.001 (***), p < 0.0001 (****).