Morphogenesis of limph nodes in Muscovy ducks during early posnatal onthogenesis

Abstract

The dynamics of mass and linear parameters of lymph nodes of ducks is a direct reflection of structural and functional transformations of their lymphatic parenchyma. The peculiarities of quantitative dynamics of tissue components of peripheral lymphatic organs at early stages of postnatal ontogenesis are to a great extent determined by advanced growth rates of their absolute mass against the background of sharp increase of their antigenic stimulation intensity. Parenchyma of lymph nodes of newborn ducklings is characterized by relatively low degree of differentiation and is represented by diffuse lymphatic tissue with no pronounced signs of its division into separate functional zones. Internally, the lymphatic channel is represented by only two lymphatic sinuses - the central one, which is located in the central part of the organ and occupies a large relative area and a discrete edge sinus, which borders on the node capsule and has a much smaller relative area and, accordingly, is located at its periphery. The organ parenchyma is a diffuse cluster of stromal and lymphatic cells in the enlarged lymphatic vessel between the central (inner) and edge (outer) lymphatic sinuses, without signs of its division into cortical and brain matter. Among the lymphatic tissue of the lymph node, reticular stroma cells and the population of small lymphocytes have the largest relative amount.