Avitaminosis XIII. Effect of Vitamin A Deficiency and Vitamin D Deficiency on Differential Leucocyte Count of the Albino Rat. 20

Abstract

Vitmin A Deficiency. Forty-nine rats were employed, 30 to 50 days of age, each animal weighing 50 to 86 gm. Of these, 31 were placed on a diet satisfactory in every respect with the exception of vitamin A, and 18 served as controls. The experimental period lasted 30 to 70 days. Various stages of the avitaminosis were produced, ranging from loss of weight with or without accompanying incipient ophthalmia to severe ophthalmia associated with pneumonia. Our results on the differential leucocyte count in vitamin A deficiency are essentially in accord with the recent findings of Turner and Loew, 1 namely, that, as the disease progresses in severity there is a relative increase of polymorphonuclear leucocytes and a corresponding decrease in lymphocytes in the majority of pathological animals compared with the litter mate controls. The extent of such relative polymorphonuclear leucocytosis and corresponding lymphopenia is 10 to 30%. What we are unable to explain, however, is why a number of animals that are apparently in advanced stages of this avitaminosis show no significant changes in the differential leucocyte count.

Total leucocyte counts were made on 6 pathological animals and on 6 controls. The extent of variation on the same control animals was so great that no noteworthy influences can be ascribed to the vitamin A deficiency. In this respect our findings are not in agreement with those of Turner and Loew who report higher values for animals suffering from this avitaminosis. No significant differences were observed in the monocyte, basophil or eosinophil counts between the pathological and control animals.

Vitamin D Deficiency. For the vitamin D work 42 animals were employed, 31 of which were placed on Steenbock and Black's ricketic diet, 2 and 11 of which served as controls.