Female reproductive impacts of dietary methylmercury in yellow perch (Perca flavescens) and zebrafish (Danio rerio).

The purpose of this study was to evaluate the effects of environmentally relevant dietary MeHg exposures on adult female yellow perch (Perca flavescens) and female zebrafish (Danio rerio) ovarian development and reproduction. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lakes basin, and the use of zebrafish allowed for a detailed analysis of the molecular effects of MeHg following a whole life-cycle exposure. Chronic whole life dietary exposure of F zebrafish to MeHg mimics realistic wildlife exposure scenarios, and the twenty-week adult yellow perch exposure (where whole life-cycle exposures are difficult) captures early seasonal ovarian development.

Reproductive effects in fathead minnows (Pimphales promelas) following a 21 d exposure to 17α-ethinylestradiol.

17α-ethinylestradiol (EE2) is a synthetic estrogen that is an active ingredient in oral contraception and hormone replacement therapy. Surveys of wastewater treatment plant effluents and surface waters throughout the world have reported EE2 concentrations in the ng/L range, and these low levels can cause significant reproductive effects in fish. This study tested the effects of three environmentally relevant EE2 concentrations: 0.

Determining the effects of a mixture of an endocrine disrupting compound, 17α-ethinylestradiol, and ammonia on fathead minnow (Pimephales promelas) reproduction.

Aquatic organisms are exposed to a multitude of contaminants and to fully understand the impact of multiple stressors on fish populations, we must first understand the mechanism of action for each toxicant and how the combined effects manifest at the level of the individual. 17α-ethinylestradiol (EE2) has been known to cause adverse reproductive effects including reduced fecundity and fertility, intersex and skewed sex ratios in fish by mimicking naturally produced estrogen at low concentrations. Ammonia can cause adverse reproductive and mortality effects in individual fish through effects or damage to the central nervous system.

Determining the effects of ammonia on fathead minnow (Pimephales promelas) reproduction.

Ammonia can cause adverse reproductive and mortality effects in individual fish by interacting with the central nervous system. The last published study that assessed the effects of ammonia on fathead minnow reproduction was a lifecycle study conducted in 1986. Our study's main goal was to re-evaluate ammonia toxicity on fathead minnow Pimephales promelas reproduction using a 20-day fecundity flow-through diluter method.