Presentation Title

Effects of androgenic compounds in aquatic sediment on endocrine function in fish

Advisor Information

Alan Kolok

Location

Dr. C.C. and Mabel L. Criss Library

Presentation Type

Poster

Start Date

7-3-2014 9:00 AM

End Date

7-3-2014 12:00 PM

Abstract

Trenbolone (Tb), a commonly used growth promoter in cattle production, begins to metabolize and degrade quickly when released into the environment. The objective of this study was to characterize that degradation, and determine the potency and biological activity of the Tb metabolites on the sentinel fish, the fathead minnow. For this experiment, we collected sediment from the Elkhorn River and spiked it with Tb. Tb was rapidly metabolized into trendione, one of its primary metabolites, such that 71% of the Tb was gone by day 4 and 84% by day 7. Female minnows exposed to Tb exhibit reductions in the expression of two genes in their livers; vitellogenin and estrogen receptor alpha, both of which are critical for reproductive development. Fish exposed to only the first four days of the exposure, when Tb was the dominant steroid in the tank, showed altered expression of the genes 10 days later, suggesting that a short term exposure can elicit long term changes in the fish. More importantly, fish exposed during the next 14 days (days 5-18) also showed altered gene expression, despite the fact that much of the Tb had already been converted into Td. Trenbolone is likely to quickly metabolize in the environment, but the metabolism does not render the compound inactive. Tb metabolites are still very potent and can adversely impact the reproduction of aquatic organisms.

This document is currently not available here.

COinS
 
Mar 7th, 9:00 AM Mar 7th, 12:00 PM

Effects of androgenic compounds in aquatic sediment on endocrine function in fish

Dr. C.C. and Mabel L. Criss Library

Trenbolone (Tb), a commonly used growth promoter in cattle production, begins to metabolize and degrade quickly when released into the environment. The objective of this study was to characterize that degradation, and determine the potency and biological activity of the Tb metabolites on the sentinel fish, the fathead minnow. For this experiment, we collected sediment from the Elkhorn River and spiked it with Tb. Tb was rapidly metabolized into trendione, one of its primary metabolites, such that 71% of the Tb was gone by day 4 and 84% by day 7. Female minnows exposed to Tb exhibit reductions in the expression of two genes in their livers; vitellogenin and estrogen receptor alpha, both of which are critical for reproductive development. Fish exposed to only the first four days of the exposure, when Tb was the dominant steroid in the tank, showed altered expression of the genes 10 days later, suggesting that a short term exposure can elicit long term changes in the fish. More importantly, fish exposed during the next 14 days (days 5-18) also showed altered gene expression, despite the fact that much of the Tb had already been converted into Td. Trenbolone is likely to quickly metabolize in the environment, but the metabolism does not render the compound inactive. Tb metabolites are still very potent and can adversely impact the reproduction of aquatic organisms.