Effects of Agrichemicals in the Elkhorn River on Endocrine Function of Juvenile Female Fathead Minnows (Pimephales promelas)
Advisor Information
Alan Kolok
Location
UNO Criss Library, Room 231
Presentation Type
Oral Presentation
Start Date
6-3-2015 9:15 AM
End Date
6-3-2015 9:30 AM
Abstract
Several studies conducted in our lab have demonstrated the effects of agrichemicals in the Elkhorn River on adult fathead minnows. However, little is known about the effects of such exposures on fish larvae. Larval exposures present novel opportunities for researchers, as such exposures may result in irreversible effects that are initiated during early development. To investigate how agrichemicals impact juvenile fathead minnows during sexual differentiation, larvae were exposed to agrichemicals at the Elkhorn River Research Station for 7 d. After the exposure, the gene expression of estrogen responsive genes, cyp19a and erα, was quantified. Interestingly, expression of cyp19a, proved to be a useful tool in determining the sex of juvenile fish, as individuals with high levels of the expression can be inferred to be female. Once the male and female fish were separated, we found that female larvae experienced significantly lower expression of these sex related genes when compared to controls. These results represent the first step by which agrichemicals in the Elkhorn River alter the sexual development of juvenile female fathead minnows. Further work must be performed to investigate whether such exposures induce chronic, lifelong negative effects.
Effects of Agrichemicals in the Elkhorn River on Endocrine Function of Juvenile Female Fathead Minnows (Pimephales promelas)
UNO Criss Library, Room 231
Several studies conducted in our lab have demonstrated the effects of agrichemicals in the Elkhorn River on adult fathead minnows. However, little is known about the effects of such exposures on fish larvae. Larval exposures present novel opportunities for researchers, as such exposures may result in irreversible effects that are initiated during early development. To investigate how agrichemicals impact juvenile fathead minnows during sexual differentiation, larvae were exposed to agrichemicals at the Elkhorn River Research Station for 7 d. After the exposure, the gene expression of estrogen responsive genes, cyp19a and erα, was quantified. Interestingly, expression of cyp19a, proved to be a useful tool in determining the sex of juvenile fish, as individuals with high levels of the expression can be inferred to be female. Once the male and female fish were separated, we found that female larvae experienced significantly lower expression of these sex related genes when compared to controls. These results represent the first step by which agrichemicals in the Elkhorn River alter the sexual development of juvenile female fathead minnows. Further work must be performed to investigate whether such exposures induce chronic, lifelong negative effects.