An androgenic agricultural contaminant impairs female reproductive behaviour in a freshwater fish

• Published in: PloS one Vol. 8; no. 5; p. e62782
• Main Authors: Saaristo, Minna, Tomkins, Patrick, Allinson, Mayumi, Allinson, Graeme, Wong, Bob B M
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 03.05.2013; Public Library of Science (PLoS)
• Subjects: Agricultural pollution; Agrochemicals - toxicity; Anabolic Agents - toxicity; Androgens - toxicity; Animal reproduction; Animals; Anthropogenic factors; Aquatic insects; Biology; Chemistry; Coercivity; Contaminants; Cyprinidae; Cyprinodontiformes - anatomy & histology; Cyprinodontiformes - physiology; Endocrine disruptors; Endocrine Disruptors - toxicity; Endocrine system; Exposure; Female; Females; Fish; Fish (Food product); Fishes; Freshwater fish; Gambusia affinis; Gambusia holbrooki; Gene expression; Male; Males; Morphology; Pimephales promelas; Pollutants; Pulp & paper mills; Reproductive behavior; Sexes; Sexual behavior; Sexual Behavior, Animal - drug effects; Sexual dimorphism; Stability; State laws; Studies; Success; Swimming; Trenbolone; Trenbolone Acetate - toxicity; Water Pollutants, Chemical - toxicity; Australia; Victoria Australia
• DOI: 10.1371/journal.pone.0062782
• ISSN: 1932-6203

Endocrine disrupting chemicals (EDCs) are a large group of environmental pollutants that can interfere with the endocrine system function of organisms at very low levels. One compound of great concern is trenbolone, which is widely used as a growth promoter in the cattle industry in many parts of the world. The aim of this study was to test how short-term (21-day) exposure to an environmentally relevant concentration of 17β-trenbolone (measured concentration 6 ng/L) affects reproductive behaviour and fin morphology in the eastern mosquitofish (Gambusia holbrooki). The mosquitofish is a sexually dimorphic livebearer with males inseminating females using their modified anal fin, the gonopodium, as an intromittent organ. Although the species has a coercive mating system, females are able to exert some control over the success of male mating attempts by selectively associating with, or avoiding, certain males over others. We found that females exposed to trenbolone approached males less and spent more time swimming away from males than non-exposed (control) females. By contrast, we found no difference in the behaviour of exposed and non-exposed males. Furthermore, exposure did not affect the anal fin morphology of males or females. This is the first study to demonstrate that exposure to an androgenic EDC can impair female (but not male) behaviour. Our study illustrates how anthropogenic contaminants can have sex-specific effects, and highlights the need to examine the behavioural responses of environmental contaminants in both sexes.