Proliferative Gill Disease (Hamburger Disease)

has become common in farmraised channel catfish. It can kill a few dozen fish over several days, or up to 100 percent of the fish in less than 3 days. Recurrence in the same pond is rare. From 1991 to 1995 PGD was the fourth most commonly diagnosed disease of catfish in the southeastern U. S., occurring in one out of every ten disease cases. This disease causes catfish to suffocate because of the severe damage to the gills. Swelling and a red and white mottling of the gills gives them a raw hamburger appearance, and many refer to PGD as hamburger gill disease (Fig. 1).