Chick Bioassay of Vitamin K Compounds Using Dicumarol and Pivalyl as Anticoagulants

CHICK bioassay procedures have been widely used to study the relative efficacy of vitamin K compounds (Perdue and Frost, 1960; Griminger, 1965; Dua and Day, 1966). Since the reduction of blood prothrombin time is the criterion used in such studies, a stress agent to sensitize the assay is desirable. Despite certain adverse side effects, sulfaquinoxaline has been used as the anticoagulant stress agent in most previous work. Snake venom has been used as the sensitizing agent on a limited basis (Matschiner and Doisy, 1966). Toxic effects of sulfaquinoxaline have been studied by Delaplane and Milliff (1948), Newbern and Buck (1956), Sanger et al. (1956) and others. Sanger et al. (1956) found that experimental birds receiving 0.1 percent sulfaquinoxaline in the feed along with alfalfa meal and vitamin K active compounds developed hemorrhages, leukocytic infiltrations, bone marrow hypoplasia and anemia. Yacowitz et al. (1955) were unable to completely protect the chicks . . .