The lymph drainage of the mammary glands in the bitch: a lymphographic study. Part I: The 1st, 2nd, 4th and 5th mammary glands.

The objective of this paper was to study the lymph drainage of the 1st, 2nd, 4th and 5th mammary glands in the bitch using indirect lymphography. The main conclusions drawn after the study of 67 normal lactating mongrel bitches were as follows: lymph drains from the first gland, usually to the axillary nodes, and, in few cases, to the axillary and superficial cervical nodes simultaneously. The second gland drains to the axillary nodes. The fourth gland usually drains to the superficial inguinal nodes, but it may, rarely, drain to the superficial inguinal and medial iliac nodes simultaneously. The fifth gland drains to the superficial inguinal nodes. Lymphatic connection between the mammary glands could not be demonstrated. Furthermore, it was confirmed that lymph can pass from one gland to another, through their common regional lymph nodes, by retrograde flow. It was demonstrated that there is a connection between the superficial inguinal lymph nodes from either side. It is suggested that lymphatic connection between the axillary and sternal nodes and between the axillary and bronchial nodes should be possible in some cases. Lymphatics of the mammary glands that cross the midline were not demonstrated.