Ethanol preference following the sucrose-fading initiation procedure.

Lever responding maintained with ethanol reinforcement at concentrations up to 20% (v/v) was initiated in non-food and -water deprived rats via a sucrose-fading procedure. Home cage two-bottle preference tests between water and 10% ethanol were conducted before (pre) and after (post) the ethanol initiation procedure to determine the effect of initial ethanol preference on ethanol initiation and of initiation on later ethanol preference. Initial preference testing found that the rats could be divided into two groups, animals with low ethanol preference scores (preference below 25%) and those with moderate ethanol preference scores (preference between 25% and 50%). All animals were successfully initiated with the sucrose-fading procedure to lever press with ethanol reinforcement. Following initiation, home cage preference was markedly increased for the initially low-preferring rats (from 12% to 43%), while moderate-preferring rats showed only slight increases (from 37% to 47%). The shift in ethanol preference was discussed in terms of the relation between ethanol preference and behavioral history.