Leslie M. Dalton, DVM1; James F. McBain, DVM2
Three cases of mucormycosis in cetaceans are reviewed. The cases were
characterized by variable symptomatology which included lethargy, anorexia, and central nervous
system signs. Laboratory tests revealed elevated white blood cell counts, erythrocyte
sedimentation rate, aspartate amino transfer erase (AST/SGOT), creatine phosphokinase, and
lactic dehydrogenase. Clinically apparent disease lasted from a few hours to 19 days prior to
death.
Mucormycosis (zygomycosis, phycomycosis) is the term used to identify
disease in humans or animals in which the etiologic agent is a member of the order Mucorales.
Organisms in this order are common in the environment, (i.e., soil, decaying fruits and
vegetables, animal excreta and old bread), and are worldwide in distribution. Invasive
infections by organisms in this order are comparatively rare, Saksenaea vasiformis was a pure
isolate from the brain and uterus of a deceased, pregnant killer whale. The uterus was the
portal of entry with the brain being infected via the hematogenous route. The organism resulted
in a necrotizing endometritis and encephalitis. Apophysomyces elegans was isolated from
the tissues of a Pacific white-sided dolphin. A second Pacific white-sided dolphin died with
identical gross and histological lesions. A diagnosis of mucormycosis was made based on the
morphology of the fungal hyphae in the tissues. There has only been one animal infection caused
by Saksenaea and no animal infections caused by Apophysomyces previously reported.