Effects of home cage lighting on drinking behavior of rats with septal lesions

Different conditions of home cage lighting did not affect the water consumption of rats with septal lesions any differently than that of control animals. However, rats with the septal area destroyed drank more water than control animals after the first postoperative week irrespective of the home cage lighting condition. They also lapped more frequently than control rats in order to obtain water. Animals housed under natural day-night lighting conditions before and after surgery consumed the most water, while rats housed in continuous illumination before and after surgery drank the smallest quantities of water, although they lapped with the greatest frequency in a drinkometer situation. Rats housed under day-night lighting conditions preoperatively and continuous illumination post-operatively were intermediate between animals of the two other conditions on all measures. The effect of changes in home cage lighting was interpreted in terms of alterations in the drinking and activity hands of the circadian cycle.