Aspectos Paramétricos do Comportamento Tipo-Ansiedade em Diferentes Estágios de Desenvolvimento de Guppies (Poecilia reticulata) no Labirinto em Cruz com Rampa

Abstract

Parametric studies of anxiety-like behavior in non-human animals are essential for increasing the validity and efficacy of these models by establishing key parameters for the manifestation of anxious responses. The Plus Maze with Ramp (PMR) was adapted as an anxiety model for adult fish, inspired by the Elevated Plus-Maze used for rodents. This research, divided into two studies, focused on adapting the PMR for adult fish to guppies (Poecilia reticulata) in the early stages of development. In Study I, a parametric analysis of the PMR for guppy larvae and juveniles was conducted. The sensitivity of the animals to different exposure times to the apparatus and water levels was assessed, with the goal of analyzing the guppies’ responses to the aversive stimulus produced by the PMR and their levels of anxiety-like response through exploration of the apparatus. Evaluations included time spent in each arm of the maze and the number of entries, representing behavioral variables. In Study II, based on the session time and water column parameters established in the first study, exposures to different concentrations of alcohol and caffeine were administered by water exposure. Was to examine the effects of these substances on anxiety-like behavior in guppies from the larval stage to adulthood. The results of both studies indicated that the PMR is a valid model for studying anxiety in guppies from the early stages of development. The variables measured in the device, such as time, water column and number of entries, allowed the induction of behavioral responses like-anxiety in these larval and juvenile animals. In addition, the results show that it was possible to evaluate the effect of alcohol and caffeine on the level of the anxiety response, which varies according to the dose, age and sex of the animals. These findings also reinforce the validity of the guppy as an animal model for investigations into anxiety behavior from the early stages of life.