Abstract: | In 40 dogs lymphatic vessels and regional lymph nodes of the heart have been prepared. Morphology of the regional lymph nodes have been studied by means of various histological techniques. Lymph outflow from the canine ventricles is realized by three (less often), or by two (more often) collectors. In very rare cases one collector is formed. From the right atrium lymph flows out in two collectors (cranial and left). Lymphatic vessels of the left atrium get into the left collector of the ventricles, or into the tracheobronchial lymph nodes. Into the same nodes gets the lymphatic vessel, forming at the border of the left and right atrii. Cranial, medial, caudal mediastinal nodes (lymphatic mediastinal system) and right, middle and left tracheobronchial lymph nodes (tracheobronchial system) are regional lymph nodes of the canine heart. In the lymph nodes of the tracheobronchial system of puppies older than one month presence of exogenic pigment and signs of fibrous degeneration of parenchyma are noted. |