SUBCHRONIC DIETARY TOXICITY OF STRYCHNINE - BOBWHITE QUAIL ARE LESS SENSITIVE THAN MALLARD DUCKS

Separate, 28-day, subchronic studies of strychnine dietary toxicity we re conducted using northern bobwhite quail (Colinus virginianus) and m allard ducks (Anas platyrhynchos). Five groups (five males five female s/group) of 29-week-old quail were fed Purina(R) Game Bird Breeder Lay ena(R) diets containing mean (+/-SD) 484.2 (+/- 17.0), 972.6 (+/- 54.0 ), 1,870.8 (+/- 176.1), 3,516.7 (+/- 68.0), and 6,083.3 (+/- 269.6) mu g/g strychnine; whereas five groups of 27-week-old mallards (five mal es five females/group) were fed similar diets containing mean (+/- SD) 18.8 (+/- 1.3), 91.1 (+/- 27.3), 235.0 (+/- 33.8), 484.2 (+/- 17.0), and 972.6 (+/- 54.0) mu g/g strychnine. Separate ''vehicle control'' ( 0.0 mu g/g strychnine) groups (five males, five females/ group) were i ncluded in each study. Strychnine toxicity was much less pronounced in quail; no observed effect concentrations (NOECs) were 972.6 (+/- 54.0 ) and 91.1 (+/- 27.3) mu g/g strychnine for quail and ducks, respectiv ely. Several possible explanations for the species effects are offered , and some practical issues affecting the conduct of long-term, dietar y toxicity studies are discussed.