Housing effects on ethanol consumption :free access and operant situations.

Abstract

I examined the effects of housing conditions (Isolated, Social) on ethanol consumption when the animals have the choice to work for ethanol or water in an operant situation as well as in a free access condition. Subjects were 30 male Long Evans Blue Spruce rats randomly assigned to 1 of 2 groups: isolated or socialized housing. Experimentation required a total of 8 phases. Phases 1 and 8 consisted of two-bottle (water vs. 5% ethanol) tests on the home cage. Phases 2 -5 involved training rats to press a lever for ethanol reinforcement using a sucrose-fading procedure. Phases 6 (1 hr,2 days) and 7 (24-hr) consisted of choice operant lever pressing for water vs. ethanol. My most important finding was that housing conditions affected ethanol consumption differently. Isolated rats consumed more ethanol in a free-access situation than socialized rats both at initial exposure and after repeated exposure. Further, in an operant situation, where the animal must press a lever for ethanol, isolated and socialized rats did not differ in ethanol reinforcement.