关键词: 香豆素类灭鼠剂, 抗凝血效应, 凝血酶原时间

Abstract: In order to study the difference between the first and the second generations of coumarin rodenticides, the continuous anticoagulative effects of warfarin, coumatetra-lyl and brodifacoum in albino rats for 384 hrs. were compared. After administration of 1/3 LD₅₀(mg/kg)by oral, the prothrombin time(Pt) of poisoned rats began abnormal in 6 hrs. , reached maximum in 48 hrs. , declined dramatically in diffreent degrees in 96 hrs. , and recovered completely in 144 hrs. The peak effect of warfarin or coumatetralyl was higher than that of brodifacoum, but the effect of brodifacoum persisted longer. The average Pt at 96 hrs. was 59.69 sec. , which is much higher than those of the other two groups (P<0.01). This shows that the effect of second generation coumarin is more persistent. Unexpectedly, Pt of wasfarin or coumatetralyl groups is even lower than that of control group(P<0.01)at 144 hrs. , but the reason of this phenominon is not known.