[Determination of glycogen in leukocytes of healthy and leukemic cattle]

In leukemic cows the percentage of leucocytes and lymphoid cells of the peripheral blood and marrow, with intensely stained violet glycogen granules in the plasma, which nevertheless exceptionally appear even in the leucocytes and lymphocytes of healthy cows, is significantly higher. Lymphocytes with a negative PAS reaction are found in both healthy and leukemic cows. PAS reaction can therefore be used as an auxiliary method for differentiating leukemic lymphocytes in a complex of further cytochemical reactions. In neutrophilous peripheral blood leucocytes of healthy and leucotic cattle the PAS reaction attained the values of ++ to +++. In the marrow of both groups an attenuated reaction was recorded in the myelocytes and promyelocytes (0 to +). Eosinophilous leucocytes and their developmental stages yielded negative PAS reaction. Monocytes showed a weak reaction in the periphery of healthy cattle whereas in the leucotic cattle the reaction was somewhat stronger, PAS reaction of the erythrocyte and thrombocyte bone marrow series was negative.