CHRONIC ECZEMA IN CATTLE.
Summer disease. Depilation. Scaly. Itchy at first. Lesions of bones, red zones representing successive attacks. Alterative tonics indicated.
Megnin records the case of an ox which on three successive springs had a miliary vesicular eruption on the loins and upper walls of the abdomen, which persisted until the advent of cold weather in the fall. The vesicles were followed by an exudate which concreted in solid crusts, enveloping the roots of the hairs which were lifted from the follicles and failed to be renewed, so that the animal entered on the winter with an appearance of alopecia. The denuded surface was red, shining and covered with a dense covering of lamelliform epidermic scales. In the early stage of the eruption there was moderate pruritus, but when the scaly stage was reached it was neither tender nor itchy to any marked degree. Tar ointments had no effect in stimulating the growth of the hair, and the skin remained bald until the next attack. The second and third years the eruption extended farther, invading not only the trunk, but the legs, and passing through the same successive stages.
The animal was butchered and the shafts of the bones were found to be abnormally red, and showed three concentric rings of deeper brown, manifestly representing the three acute attacks and resembling the concentric rings formed in growing bones when the young animals are fed on madder.
The manifest disorder of nutrition in this chronic skin disease, is an argument for the treatment by alterative tonics, such as arsenic, as well as for the employment of tonics and corroborants in general. In such cases the presumption is that local treatment would be useless or nearly so until the general disorder could be repaired.