Branching Patterns of the Subclavian Arteries in German Shepherd Dogs

Abstract

This study is the first report of the branching pattern of the four major branches of the subclavian artery in German Shepherd dogs. A total 116 subclavian artery casts made of silicon under mean arterial pressure were analysed. The casts were classified according to their branching order and the pattern of the first two branches of the vertebral artery and costocervical trunk. The three subtypes of each major type were based on the branching order or level of the next two branches (the superficial cervical artery and internal thoracic artery). Eleven of 12 possible subtypes were found in the samples. The number of dogs having the same branching subtype of the left and right subclavian arteries was not greater than those having a different subtype. The distance between the first and last branches of the subclavian artery was always longer on the left side than on the right. However, gender-based differences were identified neither in the subtype patterns nor in the distance between the branches. These results suggest a variable branching of the subclavian arteries with frequent differences of the branching pattern on the left and right sides in German Shepherds.