ALCOHOL AS A FOOD - A COMMENTARY ON RICHTER

The present study examined the maintenance of voluntary alcohol intake in male Long-Evans rats. A microstructural analysis of consummatory b ehaviors (food, alcohol water) was carried out using a computerized dr inkometer system. In this sample of animals, there was no association (r = 0.07) between total food intake and total alcohol intake. There w as no compensation for the extra calories ingested in the form of alco hol via a reduction in total food intake, or a reduction in food bout sizes associated with pre- or postprandial alcohol consumption. Furthe r microstructural analyses determined that there were no significant d ifference between water and alcohol in terms of their distribution in relation to food (non-, pre-, or postprandial bouts). Of the total of 586 bouts of fluid intake analyzed, 45.6% were consumed postprandially , with a similar number (43.2%) consumed nonprandially. A comparison o f the size of food bouts associated with different fluid bout types (p re- or postprandial) indicated that food bouts were the same size rega rdless of whether they were accompanied by water or alcohol. A final a nalysis determined that 55% of the total daily alcohol intake was cons umed postprandially, and that the sizes of non-, pre-. or postprandial fluid bouts were significantly different for water vs. alcohol. Post hoc pairwise comparisons found that alcohol postprandial bouts were si gnificantly larger than all types of water bouts. Alcohol and water bo uts ranged in size from <0.5 ml to >5.5 ml There was a significant dif ference in the distribution of bout sizes with more alcohol bouts at t he high end of the distribution. Only 24% of the water bouts were >2.5 ml compared to 48.4% of the alcohol bouts. The results of this study demonstrate that rats organize their consummatory behavior in many dis crete, short bouts. There were considerable individual differences in alcohol preference, alcohol-bout frequency, duration, and size, as wel l as the prandial distribution of bouts. All of these variables togeth er produce the ''pattern'' of alcohol intake in individual animals, an d is likely to influence the level of intoxication achieved. Although rats do not dissociate their alcohol intake from normal feeding patter ns, alcohol bouts occurring postprandially are significantly larger th an other bouts of fluid consumption, suggesting that animals perceive the pharmacological effects of and are affected by the alcohol they co nsume. In animals with a preference for alcohol solutions, it is unlik ely that alcohol is consumed as a food. Copyright (C) 1996 Elsevier Sc ience Inc.