A female weanling northern elephant seal (Mirounga angustirostris) presented to The Marine Mammal Center in Sausalito, California, USA, in poor body condition. An esophageal obstruction was diagnosed by contrast radiography and esophagoscopy, but despite extensive diagnostics and supportive care, the seal died 6 days later. On postmortem examination, the right aortic arch was persistent, forming a vascular ring anomaly with a patent ductus arteriosus that compressed the distal esophagus. Aplasia of the right cribiform plate and hypoplasia of the right olfactory nerve was also identified. A review of necropsy reports from January 1988 to December 2003 revealed 16 severe congenital anomalies in 454 juvenile northern elephant seals that stranded in northern California.
Journal of Wildlife Diseases
Vol. 44 • No. 2
April 2008
Vol. 44 • No. 2
April 2008
congenital anomaly
Cribiform plate aplasia
ligamentum arteriosum
Mirounga angustirostris
northern elephant seal
olfactory nerve hypoplasia
patent ductus arteriosus
