Lineage factor evaluation of aversive learning test anxiety levels in good and bad performance animals: Wistar versus Sprague Dawley

Abstract

The two-way active avoidance is an animal model of aversive learning, in which we can observe two distinct subpopulations of animals, the good and the poor performers. It has been suggested that there is a correlation between the aversive system and the anxiety levels, then the aim of this work is to elucidate whether there are previous differences between the level of fear and anxiety in these animals. For that, Male Wistar rats weighing between 250-300g will be used. The animals will be received at the Vivarium, for a 72 hours habituation period. Then the anxiety level of these animals will be evaluated using the most used anxiety model nowadays, the elevated plus maze (Pellow et al., 1985). The animals will be individually placed in the central area of the maze with the head directed toward one of the closed arms with the possibility to freely explore the equipment for 5 minutes. The experimental sessions will be monitored and recorded and it will be done the behavioral analysis to evaluate the number and time spent in the open and closed, the percentage of entries into open arms, the exploration the open ends, rearing, stretching and dipping and grooming. Next, the animals will be trained for seven days in the two-way active avoidance to determine the good and poor performers (display of less than avoidance responses for at least 2 consecutive days). It will be correlated the level of anxiety of the animals with the performance in the avoidance test.