The anatomy of the equine stomach, the close proximity of the exiting duodenum and the entering oesophagus along with the well developed cardiac sphincter, make it difficult for the horse to vomit. However on rare occasions it does occur. | The anatomy of the equine stomach, the close proximity of the exiting duodenum and the entering oesophagus along with the well developed cardiac sphincter, make it difficult for the horse to vomit. However on rare occasions it does occur. |