Abstract

Two immature female bottlenose dolphins (Tursiops truncatus) were found stranded on the U.S. Atlantic coast. Necropsy and histopathologic examination of both dolphins demonstrated acute necrotizing lesions in multiple organ systems. Commonly seen in these lesions were cells with enlarged nuclei that contained single 4-6µm diameter homogeneous eosinophilic inclusion bodies which were often surrounded by a clear halo. Ultrastructural examination revealed that intranuclear inclusions contained 90-110 nm-diameter viral particles with electron-dense cores and hexagonal profiles. Rarely, viral particles were present in the cytoplasm and were surrounded by variably electron-dense envelopes; enveloped virions were 140 nm in diameter. Polymerase chain reactions targeting the DNA polymerase and terminase genes of herpesviruses were carried out on unfixed tissues of both animals, and analysis of the DNA products indicated the presence of two novel alpha herpesviruses. The gross, histologic, ultrastructural, and molecular genetic findings indicate disseminated herpes viral infections; the lack of evidence of any other primary pathogenic organisms supports the conclusion that the alpha herpesviruses caused the deaths of the two dolphins. This is the first report of disseminated herpes viral infection in cetaceans.

References

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