PSVIII-6 Cytomorphological features of the bone marrow of hypotrophic piglets

The experiment was conducted on newborn hypotrophic piglets obtained from sows of the 3rd–4th farrow on the farm in the Voronezh region. Bone marrow for histochemical and ultrastructural studies was selected from hypotrophic piglets with a body weight less than 800 g (n = 13). The material for electron microscopy was carried out in 2.5% glutaraldehyde in 0.114 M colloid buffer in the cold with postfixation in 1% solution of osmium tetroxide in the same buffer. The material was enclosed in epon-812. Semithin sections were stained with azur-2 in combination with the main fuchsin and were examined under Leica light microscope. Ultrathin sections were prepared on Ultracut (Leica) ultramicrotome, contrasted with lead citrate and uranyl acetate and examined under EM-208 (Philips) electron microscope. In hypotrophic piglets, the cells forming in the red bone marrow are located as islands. Hypoplasia of cells of the hemopoetic series occurred, proerythroblasts and megacaryoblasts were observed in insignificant quantity. Megakaryocytes were closely adjacent to sinusoidal capillaries, and a part of their cytoplasm penetrated into the lumen of blood vessels. Separating fragments of cytoplasm in the form of platelets were transferred to the blood flow. Light mitochondria with a few small electron-dense cristae were observed in the ultrastructure of cells of the bone marrow. The emergence of immature forms, which indicated bone marrow function disorder or its barrier damage, was also observed in the blood flow. At the same time there occurred a decrease in the number of differentiated cells and their differentiation disorder, which could lead to immunodeficiency state. Differentiation of cells in the bone marrow of hypotrophic piglets is impaired, and that is why the body is not provided with a sufficient number of blood cells. Blast cells, which appear in the blood flow, cannot fully perform their functions, resulting in immunodeficiency and anemia.