Grey seals: morphometric parameters of erythrocytes

The first 3-4 months of postnatal ontogenesis of true seals are characterized by the most significant changes in the cellular composition of the blood, which is associated with active processes of formation of bone marrow hematopoiesis and development of cellular defense mechanisms. The level of oxygen reserves in the blood of puppies in the period of their aquatic environment development (in search of food and protection from predators) depends on the functional state of red blood cells. In this regard, it is important to study the morphofunctional properties of red blood cells in seals at different stages of postnatal ontogenesis. For comparison the next age-related groups of grey seals ( Halichoerus grypus ) have been selected: infants (0-1 week), actively feeding with mother's milk (2-3 weeks), animal after milk feeding (1-1,5 months), pinnipeds after the end of milk nourishment until independent feeding (3-4 months) and adult animals (1,0 and 3,5 years). The blood of all age groups of gray seals is dominated by discocytes, and there are also reversible (echinocytes, stomatocytes) and irreversible (codocytes, schizocytes, spherocytes), immature and young forms of red blood cells...