5.2. Social Interaction Test

The social interaction test (SIT) was performed using a black PCV box (67 × 57 × 30 cm, length × width × height). The arena was dimly illuminated with an indirect light of 18 Lux [83]. Each social interaction experiment involving two rats was carried out during the light phase of the light/dark cycle. The rats were selected from separate housing cages to make a pair for the study. The paired rats were matched for body weight within 15 g. Each pair of rats was diagonally placed in opposite corners of the box facing away from each other. The behavior of the animals was measured over a 10-min period. The test box was wiped clean between each trial. Social interaction between two rats was expressed as the total time spent in social behavior, such as sniffing, genital investigation, chasing, and fighting with each other. The number of episodes was counted as a separate paradigm. The SIT was performed 4 times: on days p30, p42, p60, and p90. Each group was composed of 16 rats (8 pairs).