Sources of blood supply to the kidneys of Ural owls

Morphological studies of the sources of vascularization of the kidneys in Ural owls were carried out at the Department of Anatomy, Histology, Physiology and Pathological Anatomy of the Institute of Veterinary Medicine and Biotechnologies of Omsk State Agrarian University in 2021. The arterial system plays an important role in the trophic function of the renal parenchyma associated with a high metabolic rate in birds, as well as the creation of hydrodynamic pressure for the formation of primary urine. The aim of the research was to study and substantiate the features of the sources of arterial blood supply to the kidneys in Ural owls. To accomplish this goal, X-ray of blood vessels previously filled with Gauch mass was carried out on five carcasses of Ural owls. The sampling of material for light-optical histological examination was carried out within 10 minutes after the slaughter of birds. In the lumbar part of the trunk of the Ural owls, the main vessel for the blood supply to the abdominal organs is the descending aorta, from which the extraorgan and intraorgan renal arteries branch off. These arteries branch out segmentally within the renal parenchyma, then each branch is divided according to the main type into interlobular, around-lobular arteries and intralobular umbrella-shaped capillaries located parallel to the corresponding renal veins. As a result of morphometric analysis, it was noted that in Ural owls the following parameters can be observed: ratio of the diameter of the cranial renal artery to the descending aorta - 16.3%, its ratio to the central aorta - 14.6%, its ratio to the caudal aorta - 23.9%. As a result of histological studies, it was established that the mucous membrane is uniform along its entire length, lined with the columnar epithelium. The muscular membrane consists of bundles of smooth fibers in the amount of 12-14 layers with a combination of connective tissue fibers. The adventitia is represented by loose connective tissue with blood vessels.