Venous circulation of the oviduct in anseriformes

The aim of the study is to study the venous system of the reproductive organs in anseriformes, which was carried out on the carcasses of Peking ducks and Italian goose at the age of 75 days. The reproductive organs of birds function with the continuous supply of essential nutrients and oxygen by the blood and the equally constant removal of metabolic products. The venous system of the oviduct in anseriformes originates with intraorgan veins, which flow into the extraorgan veins and then, after the formation of the dorsal and ventral oviducts veins, enter the caudal portal renal left vein. The venous outflow from the oviduct is carried out through the extraorgan veins, which carry blood from the departments of various functional significance, and has a certain direction. Through the dorsal vein of the funnel, blood flows into the cranial portal renal left vein. From the proteinaceous section and the uterus the blood flows into the caudal portal renal left vein, and from the vagina - into the external iliac vein. After the venous blood enters the kidney, it is filtered through its parenchyma, and flows into the caudal portal renal left vein. From the anterior part of the proteinaceous section, the blood flows into the cranial proteinaceous vein, from the middle part - into the middle proteinaceous, and from the caudal part blood is carried out into the caudal proteinaceous vein. In the area of the oviduct, there is a division of branches from I to V order in the form of highly convoluted anastomoses with different diameters, forming venous networks and plexuses, creating additional sources of blood supply. Through these anastomoses, a rapid distribution of blood is carried out, which is a good compensatory mechanism, providing a good adaptation to the rapid distribution of blood throughout all parts of the oviduct. There are no valves in the venous system of the oviduct that prevent blood from flowing back. There is a great tortuosity of the venous vessels and capillaries located in the uterine wall, the length of the venous vessels increases and their rupture is prevented.