title: Strychnine alkaloid and avian reproduction: effects occur at lower dietary concentrations with mallard ducks than with bobwhite quail.
abstract: Separate subchronic reproductive toxicity studies were conducted using mallard ducks (Anas platyrhynchos) and northern bobwhite quail (Colinus virginianus). Three groups (32/group; 16 male-female pairs) of 17-week-old ducks (F0 generation) were fed Purina Game Bird Breeder Layena diets containing mean (+/-SD) 33.2 (+/-2.7), 68.9 (+/-1.8), and 140.9 (+/-5.1) microg/g strychnine for 20 weeks, with some pairs in each group fed control diet during a subsequent 3-week recovery period. Three groups (32/group; 16 male-female pairs) of 19-week-old quail (F0 generation) were fed similar diets containing mean (+/-SD) 279.2 (+/-10.1), 557.4 (+/-43.5), and 1,113.6 (+/-46.6) microg/g strychnine for 22 weeks without a recovery period. Separate groups of ducks and quail (32/group; 16 male-female pairs) were also fed control diets (0.0 microg/g strychnine) in each study. There were 16 weekly collections of eggs for the mallard study (13 for the diet-exposure period and 3 for the recovery period), and 11 collections for the quail study. Eggs laid during the last 13 and 10 weeks of the diet-exposure periods for ducks (plus 3 weeks of the recovery period) and quail, respectively, were incubated. Each hatch of F1 generation ducklings and chicks was observed for 14 days. Key results were: (1) the no observed adverse effect levels (NOAELs) for F0 ducks and quail were 33.2 and 1,113.6 microg/g strychnine, respectively--quail showed no reproductive effects at the current doses; (2) decreased egg production and hatching success occurred for mallard hens fed mean 140.9 microg/g strychnine diets; and (3) "normal-hatching" ducklings from eggs of F0 mallards fed mean 140.9 microg/g strychnine diets suffered greater mortality than ducklings from the other diet groups. Possible mechanisms of strychnine action on avian reproduction are discussed.
authors.affiliation: Bio-Life Associates, Ltd., Neillsville, Wisconsin 54456, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Pedersen
authors.forename: R T
authors.initials: RT
authors.lastname: Sterner
authors.forename: M J
authors.initials: MJ
authors.lastname: Goodall
mesh_terms: D000818:Animals; D004032:Diet; D004305:Dose-Response Relationship, Drug; D004372:Ducks / Q000502:physiology*; D004531:Eggs; D005260:Female; D008297:Male; D019055:No-Observed-Adverse-Effect Level; D010058:Oviposition / Q000187:drug effects / Q000502:physiology; D011042:Poisons / Q000008:administration & dosage / Q000633:toxicity*; D011784:Quail / Q000502:physiology*; D012098:Reproduction / Q000187:drug effects*; D013331:Strychnine / Q000008:administration & dosage / Q000633:toxicity*; D015996:Survival Rate
chemical_list: D011042:Poisons; D013331:Strychnine