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Biological characterisation of Sarcocystis neurona isolated from a Southern sea otter (Enhydra lutris nereis)

D. S. Lindsay·N. J. Thomas·J. P. Dubey
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Abstract

Sarcocystis neurona was isolated from the brain of a juvenile, male southern sea otter ( Enhydra lutris nereis ) suffering from CNS disease. Schizonts and merozoites in tissue sections of the otter’s brain reacted with anti- S. neurona antiserum immunohistochemically. Development in cell culture was by endopolyogeny and mature schizonts were first observed at 3 days postinoculation. PCR of merozoite DNA using primer pairs JNB33/JNB54 and restriction enzyme digestion of the 1100 bp product with Dra I indicated the organism was S. neurona . Four of four interferon-γ gene knockout mice inoculated with merozoites developed S. neurona -associated encephalitis. Antibodies to S. neurona but not Sarcocystis falcatula , Toxoplasma gondii , or Neospora caninum were present in the serum of inoculated mice. This is the first isolation of S. neurona from the brain of a non-equine host.

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D. S. Lindsay, N. J. Thomas, J. P. Dubey. 2000. Biological characterisation of Sarcocystis neurona isolated from a Southern sea otter (Enhydra lutris nereis). https://doi.org/10.1016/s0020-7519(00)00034-5

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