Fig. 1. During general anesthesia with the sheep lying on one side and the forelimbs lightly pulled caudally (neck axis, 110–120°) by a second investigator, the landmarks were determined. At the base of the neck, surface landmarks were easily determined by means of palpation and examination. The broken arrow (1) shows the entry site of the needle. The brachial plexus was identified using a nerve stimulator. The block needle was inserted and advanced caudally, dorsally toward the midpoint of the dorsal vertebral spine and along an oblique axis nearly parallel to the long axis of the sheep’s neck and laterally with the plane of the operating table grossly visualized by angle (2).