title: Parental Whole Life Cycle Exposure to Dietary Methylmercury in Zebrafish (Danio rerio) Affects the Behavior of Offspring.
abstract: Methylmercury (MeHg) is an established neurotoxicant of concern to fish-eating organisms. While most studies have focused on the fish consumers, much less is known about the effects of MeHg on the fish themselves, especially following exposures to chronic and environmentally relevant scenarios. Here we evaluated the behavioral effects of developmental MeHg insult by exposing parental generations of zebrafish to an environmentally realistic MeHg dietary concentration (1 ppm) and two higher concentrations (3 and 10 ppm) throughout their whole life span. Upon reaching adulthood, their offspring were analyzed through a series of behavioral tests, including the visual-motor response (VMR) assay, analysis of spontaneous swimming and evaluation of foraging efficiency. The VMR assay identified decreased locomotor output in the 6 day postfertilization (dpf) offspring of fish exposed to 3 and 10 ppm MeHg. However, in a second test 7 dpf fish revealed an increase in locomotor activity in all MeHg exposures tested. Increases in locomotion continued to be observed until 16 dpf, which coincided with increased foraging efficiency. These results suggest an association between MeHg and hyperactivity, and imply that fish chronically exposed to MeHg in the wild may be vulnerable to predation.
authors.affiliation: School of Freshwater Sciences, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53204, United States.
authors.forename: Francisco X
authors.initials: FX
authors.lastname: Mora-Zamorano
authors.affiliation: School of Freshwater Sciences, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53204, United States.
authors.forename: Rebekah
authors.initials: R
authors.lastname: Klingler
authors.affiliation: Department of Fisheries and Wildlife, Lyman Briggs College, Michigan State University , East Lansing, Michigan 48824, United States.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Murphy
authors.affiliation: Department of Natural Resource Sciences, McGill University , Ste-Anne-de-Bellevue, Quebec H2X 3P9, Canada.
authors.forename: Niladri
authors.initials: N
authors.lastname: Basu
authors.affiliation: Department of Natural Resource Sciences, McGill University , Ste-Anne-de-Bellevue, Quebec H2X 3P9, Canada.
authors.forename: Jessica
authors.initials: J
authors.lastname: Head
authors.affiliation: School of Freshwater Sciences, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53204, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Carvan
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004032:Diet; D008767:Methylmercury Compounds / Q000494:pharmacology; D013550:Swimming; D015027:Zebrafish
chemical_list: D008767:Methylmercury Compounds