Trenbolone causes mortality and altered sexual differentiation in Xenopus tropicalis during larval development.
Environ Toxicol Chem
; 31(10): 2391-8, 2012 Oct.
Article
in En
| MEDLINE
| ID: mdl-22847831
Trenbolone is an androgen agonist used in cattle production and has been measured in aquatic systems associated with concentrated animal-feeding operations. In this study, the authors characterized the effects of aqueous exposure to 17ß-trenbolone during larval Xenopus tropicalis development. Trenbolone exposure resulted in increased mortality of post-Nieuwkoop-Faber stage 58 tadpoles at concentrations ≥100 ng/L. Morphological observations and the timing of this mortality are consistent with hypertrophy of the larynx. Development of nuptial pads, a male secondary sex characteristic, was induced in tadpoles of both sexes at 100 ng/L. Effects on time to complete metamorphosis or body sizes were not observed; however, grow-outs placed in clean media for six weeks were significantly smaller in body size at 78 ng/L. Effects on sex ratios were equivocal, with the first experiment showing a significant shift in sex ratio toward males at 78 ng/L. In the second experiment, no significant effects were observed up to 100 ng/L, although overall sex ratios were similar. Histological assessment of gonads at metamorphosis showed half with normal male phenotypes and half that possessed a mixed-sex phenotype at 100 ng/L. Hypertrophy of the Wolffian ducts was also observed at this concentration. These results indicate that larval 17ß-trenbolone exposure results in effects down to 78 ng/L, illustrating potential effects from exposure to androgenic compounds in anurans.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sex Differentiation
/
Sex Ratio
/
Trenbolone Acetate
/
Water Pollutants, Chemical
/
Xenopus
Type of study:
Etiology_studies
Limits:
Animals
Language:
En
Journal:
Environ Toxicol Chem
Year:
2012
Document type:
Article
Affiliation country:
Estados Unidos
Country of publication:
Estados Unidos