Studies of the Chick Edema Disease

Abstract

Feeding and injection studies have been performed with synthetic compounds which produce edema and pathological changes in S.C. White Leghorn chicks. Polychlorinated derivatives of dibenzo-p-dioxin were prepared either by chlorination of dibenzo-p-dioxin or by pyrolysis of 2,3,4,6-tetrachlorophenol and pentachlorophenol. The compounds prepared were administered to chicks by either oral feedings, oral intubation or intra-abdominal injection. Results of the feeding studies indicated that the hexachloro derivatives of dibenzo-p-dioxin most readily elicited the edema aspect of the chick edema disease but had low lethality, whereas the derivatives containing 3 and 4 chlorine atoms per molecule also caused edema but were the most lethal of the compounds tested. Hepta-and octachloro-dioxins, although capable of producing evidence of disease, were less toxic than the other polychlorinated derivatives. The pyrolytic product of 2,3,4,6-tetrachlorophenol, a mixture of predominantly hexa- and heptachlorodibenzo-p dioxins, was toxic when administered in single doses by way of oral intubation or by intra-abdominal injection.