Selection of a Single Ethanol Test Solution in Free-Choice Studies with Animals

Abstract

A method is described whereby a single test solution can be employed in short-term animal studies to obtain reliable selection-avoidance functions for ethanol. Initially, a selection threshold is determined in each animal by offering water and a concentration of ethanol, beginning at 3%. The ethanol content is increased by 1 percentage point on successive days. A single test percentage is then selected which is 3 percentage points greater than the concentration just above the selection threshold, defined as the highest concentration at which the ethanol solution constitutes half of the animal''s total daily fluid intake. The procedure eliminates the problems associated with the arbitrary use of a single test solution.