May 1922

Document Type


Degree Name



Dept. of Physiology


University of Oregon


In some early work in which we were using a Vitamin A deficient diet, we experienced considerable difficulty which we attributed to variations in the Vitamin A factor in our basal diet. The results that we obtained were rather unsatisfactory in the following respects: 1. No specific opthalmia occurred. 2. Cessation of growth was in all cases obtained but loss in weight followed in only a few instances. 3. I was necessary to run the experiment for a much longer period of time than would have been necessary with a more highly purified diet. 4. Death due to the deficiency was greatly delayed. Because of these objections we felt that there was ample reason to believe that Vitamin A was present in amounts sufficient to prevent the classical signs of a Vitamin A deficiency and that it had gained access through some ingredient or ingredients of the diet which we had been led to believe was practically devoid of this factor.




School of Medicine



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