Morphology of the Vascular Ring Produced by the Right Subclavian Artery in Four Calves

Abstract

The vascular ring produced by the right subclavian artery was observed in four calves. In these cases the branch of the aortic arch was a brachiocephalic trunk originating from the proximal portion of the left aortic arch. In cases 1 to 3 the right subclavian artery was derived from the bisubclavian trunk originating from the brachiocephalic trunk, and the right subckavian aetery in case 4 arose from the brachiocephalic trunk as the first branch of the trunk.