Effects of Re-Exposure to Plus Maze With Ramp in Guppies: Habituation and Sexual Differences

One of the tools to study anxiety is behavioral animal models. Traditional models developed in rodents can be adapted to fishes. The Plus Maze with Ramp (PMR) is a fish-like-anxiety model based on the Elevated Plus Maze, a canonical model of the rodent-like-anxiety model. Literature suggests that the Elevated Plus Maze presents sex and behavior differences of rodents between the first and the other expositions to the apparatus, an effect known as "one-trial tolerance." The present study objective was to verify the effects of guppies sex and re-exposure over the exploration parameters of PMR. To do this, both sex adult groups performed five sessions (5 min) in the PMR with different intervals inter-sessions (30 min, 60 min, 120 min, 24 hr). Our data show that the PMR environment produces an avoiding behavior from the arms with ramp; the re-exposure to the apparatus cause habituation to the environment, with possible tolerance, but not one-trial tolerance, with sex-dependent related effects. The data indicate the possibility and validity of PMR use as a like-anxiety model in this species. Public Significant Statement Guppies exhibit similar anxiety behavior to zebrafishes when exposed to PMR. Re-exposure to PMR causes habituation in guppies, like in many vertebrates. There is sexual dimorphism in guppies behavior exposed to PMR with sensibilization only in males.