Alcohol consumption by rat and mouse strains. Functions of taste and alcohol deprivation.

Abstract

Five Sprague-Dawley (S-D) rats, 5 Long-Evans (L-E) rats and 5 C57Bl mice were offered a 10% (vol/vol) alcohol solution in water, or water on day 1-23; on day 24-28 only water; on days 29-35 the 10% alcohol solution or water; on days 36-40 only water; on day 41 a 10% alcohol solution sweetened with 4% sucrose and 0.25% saccharin, or water; and on days 42-47 the 10% alcohol solution or water. During days 1-23 the mean alcohol selection (the intake of alcohol solution in percentages of total fluid intake) increased from about 56 to 100% in the mice (P < .05); from about 49 to 50% in the L-E rats; and from about 12 to 25% in the S-D rats. After alcohol deprivation, on day 29, the respective proportions were 92, 61 and 48%; the difference between day 23 and day 29 was significant in the S-D rats. When the alcohol was sweetened (on day 41) the respective mean percentages were 80, 88 and 80. The effect of the sweet taste (the difference between days 35 and 41) was significant in both groups of rats (P < .01). There were no significant differences in consumption in any group between day 19-23 and 43-47, indicating no lasting change in alcohol selection. The results indicate an initial increase in intake of the alcohol solution in the C57Bl mice, an alcohol deprivation effect in the S-D rats, an attraction to a sapid alcohol solution in the 2 rat strains, and a possible negative alcohol deprivation effect in the C57Bl mice (92% selection on day 35 vs. 80% on day 41).