Gills are pale and thickened, with gray clumps of mucus. Frequently, the surfaces of the thickened gill areas were lined by a single layer of angular, dome-shaped cells that appeared somewhat distinct from the underlying epithelium. Small mats of Gram-negative filamentous bacteria were commonly observed in the nonhyperplastic gill regions, and these were infrequently associated with necrosis of individual gill epithelial cells. Sections of gill demonstrating the segmental nature of the epithelial hyperplasia. Arrows denote relatively unaffected gill areas.
Arrowhead indicates site of filament fusion.
Last Updated October 25, 2000.