ANATOMICAL AND HISTOLOGICAL STRUCTURE OF THE KIDNEYS OF THE GRASS SNAKE (NATRIX NATRIX)

Abstract

The research findings show that the kidneys of the grass snake (Natrix natrix) are elongated flattened, there is no differentiation between the cortex and medulla, from the outside the organ is protected by a layer of adipose tissue. As a feature of the histological structure of the common grass snake kidneys, one can distinguish group accumulations of vascular glomeruli in the cortical substance, cellular polymphorism in the structure of the walls of the proximal and distal convoluted tubules, as well as their expansion and overflow of the lumen with urates. This feature, in our opinion, may also have an adaptive value, characterized by the ability of the kidneys, in the absence of a bladder, to convert waste nitrogenous compounds into uric acid, which is a hardly soluble substance, therefore, it is excreted using a small amount of water. When studying the collecting ducts of the common snake kidneys, the presence of a highly turbid cytoplasm with an indistinguishable nucleus inside the cell was noted. The obtained results of the research complement and systematize the information about the topography and structural organization of the urinary organs of snakes, which is recommended for breeders and veterinarians to take into account when performing diagnostic and surgical procedures in this species of reptiles.