A Lethal Dermatitis in Chickens Produced by External Application of Fat

Abstract

It was noticed during the course of a joint experiment of the Institute of Experimental Biology and the Poultry Division of the University of California that Single Comb White Leghorn chicks fed purified diets containing 40% fat contracted a severe dermatitis. This dermatitis was found not to be of nutritional origin, since chicks on a normal diet whose entire skin was coated with the same fat developed the same dermatitis and died within 3 to 5 days. One or two applications were sufficient in the case of chicks 4-5 weeks old; older birds were more resistant. Furthermore, the ingestion of the purified diets containing 40% fat was shown to be harmless if care was taken to prevent the fat from coming in contact with the superficial skin. Thirty-one chicks were used in the following experiment. They were kept in battery brooders provided with wire mesh floors, and fed the normal chick mash. The 6 control chicks remained in perfect health. The coating was performed by gently applying the oil or liquefied fat (heated to about 42° C) to the skin of the chick by means of a cotton swab, or by pouring it between the feathers directly onto the skin. The results of such treatment are given in Table I. Coating a limited area of the body produced a dermatitis limited to that area. The chick in this case survived the treatment. The following treatments, applied to chicks of the same age, failed to produce the dermatitis: 1. Injection of fresh or rancid fat (lard) in amounts which, when applied externally, caused dermatitis and death. 2. Subjection of the skin of the chick's entire body (with the exclusion of the head) to an atmosphere of CO2 for a period of 7 days.