Bacillary hemoglobinuria in a free-ranging elk calf.

A dead elk (Cervus elaphus roosevelti) calf was diagnosed with bacillary hemoglobinuria, a toxemia caused by the bacterium Clostridium haemolyticum. The mortality occurred in southwest Washington, USA (46 degrees 13'N, 123 degrees 22'W), in an area in which several previous mortalities, suspected but not conclusively diagnosed to be either bacillary hemoglobinuria, enterotoxemia, or leptospirosis, occurred. This is the first reported incidence of mortality attributable to bacillary hemoglobinuria in free-ranging elk. Similar deaths of young elk in the area suggest that mortality from this disease may be common locally.