Question

Which structure is avoided when drawing blood from the right jugular vein of a horse

Answer 1

Carotid Artery

Also, the jugular vein is separated from deep structures within the carotid sheath by the Omohyoideus m (which acts as a backstop to prevent you from injecting things into the horse's common carotid artery instead of the external jugular vein. It could cause excitability, collapse, brain damage, or death).