Functional behavior and reproduction in androgenic sex reversed zebrafish (Danio rerio)

• Published in: Environmental toxicology and chemistry Vol. 29; no. 8; pp. 1828 - 1833
• Main Authors: Larsen, Mia G., Baatrup, Erik
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01-08-2010; Blackwell Publishing Ltd
• Subjects: 17β-Trenbolone; Acetates; Animal behavior; Animal populations; Animal reproduction; Animals; Beef cattle; Behavior, Animal - drug effects; Cattle; Courtship behavior; Danio rerio; Disorders of Sex Development - chemically induced; Disorders of Sex Development - veterinary; Endocrine disruption; Endocrine Disruptors - toxicity; Exposure; Female; Females; Fish; Fish populations; Flow system; Freshwater; Genotype & phenotype; Male; Males; Metabolites; Natural watercourses; Populations; Reproduction; Reproduction - drug effects; Sex; Sex Characteristics; Sexual Development - drug effects; Sexual maturity; Steroids; Toxicology; Trenbolone Acetate - toxicity; Water Pollutants, Chemical - toxicity; Watercourses; Zebrafish; Zebrafish - anatomy & histology; Zebrafish - physiology
• ISSN: 0730-7268; 1552-8618; 1552-8618
• DOI: 10.1002/etc.214

Endocrine‐disrupting chemicals released into natural watercourses may cause biased sex ratios by sex reversal in fish populations. The present study investigated the androgenic sex reversal of zebrafish (Danio rerio) exposed to the androgenic compound 17β‐trenbolone (TB) and whether sex‐changed females would revert to the female phenotype after cessation of TB exposure. 17β‐Trenbolone is a metabolite of trenbolone acetate, an anabolic steroid used as a growth promoter in beef cattle. 17β‐Trenbolone in runoff from cattle feedlots may reach concentrations that affect fish sexual development. Zebrafish were exposed to a concentration of 20 ng/L TB in a flow‐through system for five months from egg until sexual maturity. This resulted in an all‐male population. It was further found that all these phenotypic males displayed normal male courtship behavior and were able to reproduce successfully, implying that the sex reversal was complete and functional. None of the phenotypic males developed into females after six months in clean water, demonstrating that androgenic sex reversal of zebrafish is irreversible. Environ. Toxicol. Chem. 2010; 29:1828–1833. © 2010 SETAC