Clinical signs of anemia in vitamin A-deficient rats

Young postweaning rats were fed diets sufficient or deficient in vitamin A to determine the effects of the deficiency on hematopoietic function and anemia. Anemia was noted in hemoglobin and hematocrit values before the signs of vitamin A deficiency (alopecia, ocular lesions and low plasma and liver retinol levels) became apparent. When liver stores of vitamin A were depleted, however, hematocrit and hemoglobin levels rose to control levels, probably from hemoconcentration. Anemia may be a component of vitamin A deficiency, but might be hidden by the dehydration accompanying vitamin A depletion. Immature rats with moderate vitamin A deficiency or young adult rats that develop the deficiency more slowly may be useful as models, whereas immature rats that develop vitamin A deficiency quickly may never show evidence of anemia