Teratogenic effects of diazinon in chick embryos I. Effects of diazinon treatment on morphology and cholinergic blocking agents

Diazinon이 계배(鷄胚)의 기형 유발에 미치는 효과 I. 계배(鷄胚) 형태와 콜린성 봉쇄약물에 미치는 효과

Teratogenic effects of diazinon were assessed on morphology of chick embryos cholinergic blocking agents. Diazinon at doses ranging from 25 to $2000{\mu}g/egg$, was injected on Day 3 of incubation. $TD_{50S}$, were different for the various teratogenic sings such as wry neck, micromelia, abnormal feathering, abnormal beak and curled claws. The threshold dose for wry neck was higher than the threshold dose for other signs; $40{\mu}g/egg$ produced substantial micromelia, abnormal feathering, abnormal beak and curled claws, but gave no sings of wry neck. In contrast to the teratogenic doses, the $LD_{50}$ of diazinon was very high(above $2000{\mu}g/egg$). One of the characteristics of diazinon-induced teratogenesis was reduction of body weight(78.8%) and body length(73.8%). Maximal teratogenic effects, scored as sings of retarded growth, wry neck, micromelia, abnormal feathering, abnormal beak, and curled claws, were produced when the insectcide was administered on the third or fourth day. The threshold dose for type II teratogenic sings including wry neck and short neck was higher than for type I including micromelia and abnormal feathering. Morphorlogical studies, using atropine and gallamine, suggested that nicotinc but not muscarinic receptors may be involved in the mechanism of diazinon-induced type II malformations.