Reproduction and Behavioral Responses of Convict Cichlid, Amatitlania nigrofasciata to Fluoxetine

Abstract

Widespread prescription of fluoxetine has led to enter into the aquatic environments which act as an endocrine disruptor for fish. This study examined the effect of fluoxetine on the reproductive consequence of convict cichlid (Amatitlania nigrofasciata), during three successive cycles of spawning. Following pair-bond formation, pairs were divided into four treatments and exposed to concentrations of 0, 0.54, 5.40 or 54.0 μg LG 1 fluoxetine in pre-acclimated spawning tanks. Reproduction was assessed by examination of Egg Number (EN), Incubation Period (IP), Hatching Ratio (HR) and Inter-Spawning Interval (ISI). At the last spawning cycle, behavior and physiochemical properties of fish were determined. Hepatosomatic index (HSI) of males/females was insignificant at the end of the experiment; however, condition factor of males showed a significant difference between 0 and 54.0 μg LG 1 fluoxetine treatments. At 5.40 and 54.0 μg LG 1 of fluoxetine, testosterone were significantly decreased in males. Both main effects of the fluoxetine concentrations and the spawning cycles were significant in the EN, HR and ISI. IP was significantly affected only by fluoxetine. The behaviors, spawning duration and fanning latency were affected in 54.0 μg LG 1 fluoxetine but time spent near the substrate and lipping display were not affected. Results indicated that fluoxetine disrupts reproduction features of convict cichlid. However, significant impacts were mainly observed at higher concentrations than those reported in natural environments (0.54 μg LG 1), so that the impact of fluoxetine on reproductive fitness of cichlid populations might be relatively low.

Field-realistic antidepressant exposure disrupts group foraging dynamics in mosquitofish

“…length, weight or condition). A fluoxetine-induced decrease in condition index has previously been reported in fish [36,41,42,49] although, typically, such effects are reported at dosages higher than those employed here [36]. Given that the effects of fluoxetine can take two to three weeks to manifest [31,32], it is possible that, over a longer duration, shifts in social foraging behaviour could result in shifts in morphology.…”

Territorial aggression in male bower-building cichlidsNyassachromiscf.microcephalusis disrupted by exposure to environmental concentrations of fluoxetine

“…microcephalus that had been treated with fluoxetine exhibited less aggression than those that had not. SSRIs have already been established to cause disruptions in fish reproductive fitness, for example decreasing testosterone levels in the male convict cichlid Amatitlania nigrofasciata (Dorelle et al, 2017; Latifi, Forsatkar and Nematollahi, 2015; Prasad, Ogawa and Prahar, 2015). In Lake Malawi cichlids, where territoriality is a key component in male mating success and reproduction, the serotonin pathway is likely to play an important role in regulating aggression.…”

“…Subjects assigned to the control group (n=12) had only water added to their tank. These concentrations were selected following reports on fluoxetine presence in the environment (Metcalfe et al, 2010; Silva et al, 2012) and literature on fluoxetine experiments with cichlids (Latifi, Forsatkar and Nematollahi, 2015; Shih, 2017). The high dose group acted as a positive control.…”

“…SSRIs temporarily increase the amount of serotonin available by blocking the reuptake of serotonin into neurons (Stahl, 1998). Within cichlids, the SSRI fluoxetine has been found to disrupt the endocrine system and reproduction in Amatitlania nigrofasciata and Cichlasoma dimerus (Dorelle et al, 2017; Latifi, Forsatkar and Nematollahi, 2015), reduce food consumption in Cichlasoma dimerus (Dorelle et al, 2020), and reduce the rate of startle and aggressive behaviours in Astatotilapia burtoni (Shih, 2017). In Shih (2017), aggression was studied in the capacity of evaluating social status and behaviour.…”