Clinicopathologic, molecular, and ultrastructural features ofinfection in 2 California sea lions with fatal necrotizing hepatitis.

Abstract

is an apicomplexan protozoal parasite that was first recognized during a mass mortality event in juvenile grey seals () in the northwest Atlantic Ocean. Since its identification, this parasite has been reported in various pinniped species and has been associated with fatal necrotizing hepatitis. Little is known of the host range of. Here we report 2 cases of California sea lions () in managed care that died following an 8-d history of inappetence, vomiting, diarrhea, and progressive lethargy with elevated hepatic enzyme activities. Postmortem examination identified hepatitis and icterus.schizonts and zoites were identified in regions of necrosis. Molecular and ultrastructural findings demonstrated the close relatedness of thisto, which produces a similar lesion in bears.