A Pannus-forming Infection of Sheep Eyes

This preliminary report is concerned with the description of a disease of the conjunctiva and cornea of sheep, of natural occurrence, which results in the formation of a pannus, not unlike that in human trachoma.The farmer from whom I obtained my diseased sheep first noticed the non-purulent infection of the conjunctiva and nictitating membrane, evidenced by congestion, edema, epiphora, as fall weather and near-freezing temperatures prevailed. Examination by him of the large flock allowed about 200 infected animals to be isolated, 10% of which had marked vascularization of the cornea. Two weeks later, when I was asked to examine the flock, less than 1% were not infected. Probably 80% suffered clinical pannus formation, and 5% superficial ulcers at the tip of the pannus. Hypopyon ulcer was seen in only those that were so blinded as to be unable to prevent injury to the cornea in trying to graze and follow the flock. No perforation of the cornea was seen. A representative animal, moderately infected, was re...