title: Acute embryotoxic effects but no long-term reproductive effects of in ovo methylmercury exposure in zebra finches (Taeniopygia guttata).
abstract: Mercury bioaccumulates in terrestrial ecosystems as methylmercury (MeHg), yet little is known about its effects on terrestrial organisms, including songbirds. The authors used a model songbird species, the zebra finch (Taeniopygia guttata), to assess short-term embryotoxic effects of in ovo MeHg exposure on hatching success and posthatching growth and nestling survival, as well as longer-term effects on mating behavior and reproduction. Egg treatment groups included a low-MeHg dose of 0.2 μg Hg g(-1) egg (n = 36), a high-MeHg dose of 3.2 μg Hg g(-1) egg (n = 49), and a control (n = 34). Doses were dissolved in nanopure filtered water and injected into the albumen on the day eggs showed signs of viability (3 d incubation). In ovo exposure to MeHg significantly reduced hatching success (53% in the high-MeHg dose group vs 94% in vehicle controls). Among hatched chicks, however, no effects of MeHg on growth, hematological variables, or nestling survival were detected. While the in ovo injection method resulted in a dose-dependent pattern of MeHg concentrations in blood of surviving chicks at 15 d and 30 d posthatching, there was evidence of rapid excretion of MeHg with nestling age during that growth period. At reproductive maturity (90 d of age), no long-term effects of in ovo exposure to MeHg on female mating behavior, reproductive effort (egg or clutch size), or growth and survivorship of offspring were observed. Environ Toxicol Chem 2016;35:1534-1540. © 2015 SETAC.
authors.affiliation: Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.
authors.forename: Maria S
authors.initials: MS
authors.lastname: Yu
authors.affiliation: Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.|Environment Canada, Science & Technology Branch, Pacific Wildlife Research Centre, Delta, British Columbia, Canada.
authors.forename: Margaret L
authors.initials: ML
authors.lastname: Eng
authors.affiliation: Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.
authors.forename: Tony D
authors.initials: TD
authors.lastname: Williams
authors.affiliation: Faculty of Agricultural and Environmental Sciences, McGill University, Ste. Anne de Bellevue, Quebec, Canada.
authors.forename: Niladri
authors.initials: N
authors.lastname: Basu
authors.affiliation: Environment Canada, Science & Technology Branch, Pacific Wildlife Research Centre, Delta, British Columbia, Canada.
authors.forename: John E
authors.initials: JE
authors.lastname: Elliott
mesh_terms: D000818:Animals; D004781:Environmental Exposure; D005260:Female; D046369:Finches / Q000254:growth & development* / Q000378:metabolism; D008297:Male; D008767:Methylmercury Compounds / Q000097:blood / Q000633:toxicity*; D010063:Ovum / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012098:Reproduction / Q000187:drug effects*; D012726:Sexual Behavior, Animal / Q000187:drug effects; D013054:Spectrophotometry, Atomic
chemical_list: D008767:Methylmercury Compounds
keywords: Hatching success; In ovo exposure; Methylmercury; Passerine; Reproduction