[Structure and blood supply of the heart valves of several domestic and wild birds].

By means of a complex technique some structural and blood supply peculiarities of the valve apparatus have been studied in 118 hearts of 8 representatives of domestic (Anser domesticus, Anas domestica) and wild (Cygnus olor, Cygnus sygnus, Chenopsis atrata, Anser anser, Anas platyrhynchos, Anas strepera) waterfowls. The investigations have demonstrated that in all the waterfowl studied the right atrioventricular ostia have only one cusp consisting mainly of transversal-striated muscular fibers. In the muscular valve, a dense vascular network and elements of the conducting system--Purkine's fibers have been determined. The main bulk of blood vessels penetrate the left atrio-ventricular valve, the aortal and pulmonary stem valves having transversal-striated muscular fibers. A part of vessels can be detected in the connective tissue stroma of the valves. In wild birds, the valve cusps possess more powerful bundles of muscular fibers and a much denser capillary network.