Sanford S E, Dukes T W
J Am Vet Med Assoc. 1978 Oct 1;173(7):852-3.
Bilateral cortical cataracts developed in approximately 30% of all sows greater than or equal to 2 1/2 years old on 4 farms in southwestern Ontario and on 2 farms in Quebec. A cataractogenic agent was not established, but hygromycin B was suspected as the cause.