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Acute fluoxetine treatment increases aggressiveness in juvenile matrinxã (Brycon amazonicus)
Carla Patricia Bejo Wolkers1,2, Mônica Serra3, Augusto Barbosa Júnior4
1Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências agrárias e Veterinárias/Centro de Aquicultura (CAUNESP), Universidade Estadual Paulista, UNESP, Jaboticabal, SP, Brazil. carlawolkers@yahoo.com.br.
Abstract:
Fluoxetine (FLX) is a selective serotonin (5-HT) reuptake inhibitor known for its effects modifying aggressiveness, personality traits, and anxiety-like behaviors. The aim of the present study was to evaluate the influence of the acute treatment, by immersion, with FLX on aggressive behavior of resident Brycon amazonicus fish. Fish pretreated with FLX presented an increase in aggressiveness, evidenced by the increase on the number of bites and chases against the intruder and a decrease in latency for the first attack, when compared to control fish. Together with previous studies, these results show the complexity of the neural modulation of the aggressive behavior in fish by 5-HTergic system.
Insights
Fluoxetine (FLX) significantly increased aggressive behaviors in Brycon amazonicus fish. This study highlights the complex role of the serotonin system in modulating fish aggression.
Area of Science:
- Neuroscience
- Ethology
- Aquatic Animal Behavior
Background:
- Selective serotonin reuptake inhibitors (SSRIs) like Fluoxetine (FLX) are known to influence aggression, personality, and anxiety.
- The serotonergic system's role in modulating aggressive behavior is complex and warrants further investigation in diverse species.
- Understanding neurochemical influences on aggression is crucial for behavioral ecology and animal welfare.
Purpose of the Study:
- To investigate the acute effects of Fluoxetine (FLX) immersion on the aggressive behavior of the Amazon tetra, Brycon amazonicus.
- To quantify changes in specific aggressive actions, such as biting and chasing, and latency to attack.
Main Methods:
- Resident Brycon amazonicus fish were treated via immersion with Fluoxetine (FLX).
- Aggressive behaviors were observed and quantified by recording the number of bites, chases, and the latency to the first attack.
- Behavioral data from FLX-treated fish were compared against a control group.
Main Results:
- Fluoxetine (FLX) pretreatment led to a significant increase in aggressive behaviors in Brycon amazonicus.
- Specifically, treated fish exhibited more bites and chases directed at intruders compared to control fish.
- A notable decrease in the latency to the first attack was observed in the FLX-treated group.
Conclusions:
- Acute Fluoxetine (FLX) exposure enhances aggressive behavior in Brycon amazonicus.
- These findings underscore the significant modulatory role of the 5-HTergic system in the neural control of aggression in fish.
- The results contribute to a broader understanding of how neurotransmitters influence social behaviors in aquatic vertebrates.
