Dorothy J. Walker

Hematopoietic Function in Avitaminosis. IV. Further Studies of Vitamin A Deficiency.

In a previous publication 1 we have suggested the occurrence of a secondary anemia in vitamin A deficiency. Our results, however, were not conclusive. We, therefore, continued this investigation with 30 more animals, 18 of which received our vitamin A deficient ration 1749.† Twelve of these rats were allowed a modification of this diet, so that one to 2% of lard was replaced by equivalent amounts of butterfat, in order to prevent sudden deaths from pneumonia frequently associated with this avitaminosis. In addition, we have studied the effect of vitamin A deficiency on the differential leucocyte count in 9 females and 9 males. In the females the disease was followed with daily examinations of the vaginal smears according to the technique of Evans and Bishop. 3 Daily records were kept of food consumption, and in the majority of animals records were also kept of the daily water intake. Bleedings were performed on each animal twice weekly and determinations were made of hemoglobin and erythrocyte counts. Specific gravity determinations were also made, in order to secure information on blood concentration. The experimental period ranged from 68 to 173 days. To summarize our results, we found no noteworthy disturbance in hematopoietic function during various stages of this avitaminosis, as characterized by the severity of ophthalmia and loss of body weight, nor any changes in the differential leucocyte count during the onset, and remission produced by vitamin therapy. Our results, therefore, do not substantiate the findings of Koessler and coworkers. 4 Although secondary anemias have been encountered in keratomalacia in man, 5 the investigators admit that other complications or infections associated with this disease may be the influencing factors rather than this avitaminosis.