| an epornitic of duck plague on a wisconsin game farm. | in april, 1973, an acute disease with a high rate of mortality appeared in a flock of 233 ducks and geese at a private game farm. most of the flock (220) were black ducks (anas rubripes) and mortality was restricted to them. in may, the remaining live birds were placed in isolation but mortality continued in black ducks and occurred in other species. the overall rate of mortality for black ducks was 93% and the case fatality rate was 97%. no hemorrhaging from either the bill or vent was observed ... | 1976 | 176478 |