You are here:
VITELLOGENIN EXPRESSION IN SHEEPSHEAD MINNOWS FROM THE PENSACOLA BAY SYSTEM
Citation:
Hemmer, M J., B. L. Hemmer, S D. Friedman, AND P S. Harris. VITELLOGENIN EXPRESSION IN SHEEPSHEAD MINNOWS FROM THE PENSACOLA BAY SYSTEM. Presented at SETAC World Congress, Portland, OR, November 14 - 18, 2004.
Impact/Purpose:
Conference abstract
Description:
Hemmer, M.J., B.L. Hemmer, S.D. Friedman and P.S. Harris. In press. Vitellogenin Expression in Populations of Sheepshead Minnows from the Pensacola Bay System (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB R1015).
This study was performed to determine if exposure of native fish populations to estrogenic substances was spatially restricted or indicative of a widespread condition. Approximately 380 adult male sheepshead minnows [SHM], (Cyprinodon variegatus) were collected from multiple sites within three local bayous located in the Pensacola, Florida area. Bayou Texar receives urban runoff from residential areas, shopping centers and local roads. Bayou Chico receives runoff from both residential and commercial facilities including a scrap metal collection facility, boat yards and marinas. Bayou Grande receives primarily urban runoff but is bordered to the south and west by a U.S. naval installation. Big Sabine, a salt marsh on Santa Rosa Island has no development within several miles and served as the reference site. Collections were performed in three distinct periods, April/May, July, and September/October which correspond to the normal reproductive season for this species at this latitude. Plasma levels of vitellogenin, an egg yolk precursor protein, was measured by direct ELISA using purified SHM vitellogenin for standards and a SHM vitellogenin specific antibody. Of the total number of fish sampled, 33% were found to have detectable levels of vitellogenin indicating exposure to either natural and/or xenoestrogenic chemicals. The highest percentage of vitellogenic males (68 of 69 collected) were observed at a site in Bayou Grande adjacent to the naval installation. This site also demonstrated the highest measured levels of vitellogenin, averaging 28 mg/ml. Extensive chemical analysis of sediment at this site including organochlorine and organophosphate pesticides, metals, PCB's and PAH's failed to identify a potentially causative agent. Percentages of vitellogenic males at all remaining sites ranged from 0 to 22%. A 5% induction incidence was found for the control site. No seasonal trends were observed in vitellogenin expression between spring (11%), summer (10%) and fall (12%) collection periods.