Female Syrian golden hamster: drinking of high concentrations of ethanol aversive to other mammals

Abstract

The present experiments were designed to determine: 1) the pattern of preference for different concentrations of ethanol in the female Syrian golden hamster ( Mesocricetus auratus), and 2) the influence of drinking ethanol on their intakes of food and total calories. A standard three-bottle preference test was undertaken in six female hamsters over an 11-day period in which water was offered together with ethanol, which was increased in concentration over 11 clays from 3% to 50% as follows: 3%, 5%, 7%, 9%, 12%, 15%, 20%, 25%, 30%, 40%, 50%. Then, each hamster was offered its individually preferred concentration for a period of 8 days until the intake of ethanol had stabilized. During the preference testing for 3–25% solutions, the proportional intakes ranged between 0.6 and 0.8 whereas the mean absolute amount consumed per day increased from 2.3 to 16.1 g/kg at the 25% concentration. However, at the 50% concentration, ethanol drinking declined substantially to 8.7 g/kg per day. The overall mean percent concentration of ethanol preferred by the hamsters was 24.2 ± 1.5%. During the following 8-day period when the maximally preferred concentration of ethanol of each hamster was offered with water, the mean intake of ethanol was 17.9 ± 1.1 g/kg per day. Throughout the test sequence, the caloric intake of the animals was maintained in that calories obtained from food declined at the same rate as the calories obtained from ethanol in rising concentrations. These results reveal that the preference for ethanol of the female hamster is well above that reported in earlier studies in which preference was defined in terms of the proportion of ethanol to total fluid intake. Differences in procedure could account for these findings because the present experiments utilized single-animal housing, a triple bottle method, and measurement of g/kg per day obtained at 11 different concentrations of ethanol.