Experimental duck plague in blue-winged teal and Canada geese

Ten adult blue-winged teal (Anas discors) and six Canada goose (Branta canadensis) goslings were inoculated with liver tissue from a natural case of duck plague in a wild mallard (Anas platyrhynchos). Four additional teal were placed in contact with the inoculated ducks. Inoculated teal died 63.5-68 hr after inoculation; two of the contact teal died 161-162 hr after exposure. Three of the goslings died 119-133 hr after inoculation, the others were killed when moribund 90-133 hr postinfection. The clinical course of disease was extremely rapid in both species. Signs were limited to sudden onset of profound weakness, ataxia, tremors and terminal convulsions. The only consistent gross lesion in the teal was a small dark spleen; half the teal also had inconspicuous foci of epithelial necrosis in the distal esophagus and in the cloaca. Goslings had more severe lesions, with focal hepatic necrosis visible in all, and mucosal necrosis over the intestinal lymphoid tissue, and intestinal hemorrhage in three birds each. Microscopic lesions in both species were similar to those reported in mallards. Duck plague might be overlooked at necropsy of blue-winged teal, because of the paucity of gross lesions.