Effects of waterborne exposure to the antidepressant fluoxetine on mosquitofish predator escape response.

F. J. MEIJIDE; I. LOZANO; F. L. LO NOSTRO

Cartagena

Congreso; XIII Congreso SETAC Latinoamérica; 2019

SETAC LA

Chemical pollution from pharmaceuticals isincreasingly recognized as a major threat for aquatic wildlife. In a previouswork, we have shown that exposure to the antidepressant fluoxetine (FLX) impairsswimming behaviour at high concentrations (25 and 50 ìg/L) but not at lowconcentrations close to environmental levels (1 and 5 ìg/L). In this study, weanalyzed the effect of FLX exposure on the escape response of femalemosquitofish Gambusia holbrooki (Cyprinodontiformes)following a stimulus simulating a predator attack. Adult fish (n=10 pertreatment) were exposed for 14 days to FLX at 0 (control), 1, 5, 25 and 50 µg/L,under semi-static conditions with daily renewal of test solutions. Followingexposure, we conducted a behavioural assay aimed at assessing the effect of FLXon mosquitofish predator avoidance response. Each fish was transferred to individualtesting aquaria with the same FLX concentration to which it had been exposedduring treatments, where they remained during three hours for acclimation. Subsequently,in a tablet pc mounted on one side of the aquarium, a black circle animationsimulating the frontal silhouette of an attacking predator was projected totrigger the escape response. The escape motion was video-recorded and analyzedwith the Tracker 5.04 video tracking software in order to determine the maximumspeed (Vmax) attained by fish during evasion. Our results indicate thatmosquitofish exhibited a tendency to an attenuated escape response withincreasing FLX concentrations, with Vmax achieved by fish exposed to 50 µg/LFLX being significantly lower than that of control fish. These results areconsistent with most studies in the literature, reporting effects in fishbehaviour following exposure to FLX concentrations above environmental levels.Lastly, our device probed to be effective for the assessment of mosquitofishescape response and is therefore proposed as a standardized method to assessthe effects of pharmaceuticals on the antipredator behaviour of small sizedfishes.