Periodic water availability is not a potent zeitgeber for entrainment of circadian locomotor rhythms in rats.
Entrainment of tilt-cage measured circadian activity rhythms to a 2 hr daily period of water availability was assessed in rats fed either an oil-chow mash, which rats readily consume in the absence of water, or dry pellet chow, which rats less readily consume in the absence of water. Four of 6 pellet fed rats but only 2 of 14 mash fed rats exhibited entrainment to water access. Periodic water availability, unlike periodic food availability, thus does not appear to be a potent zeitgeber for circadian activity rhythms in the rat. The entrainment that does occur in some rats may result from shifting of food intake to coincide with the availability of water.
D000818:Animals; D002940:Circadian Rhythm; D003463:Cues; D004327:Drinking Behavior / Q000502:physiology; D005247:Feeding Behavior / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D014868:Water Deprivation / Q000502:physiology*