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Veterinary parasitology2010; 170(1-2); 20-29; doi: 10.1016/j.vetpar.2009.12.045

Molecular characterization of Sarcocystis neurona strains from opossums (Didelphis virginiana) and intermediate hosts from Central California.

Abstract: Sarcocystis neurona is a significant cause of neurological disease in horses and other animals, including the threatened Southern sea otter (Enhydra lutris nereis). Opossums (Didelphis virginiana), the only known definitive hosts for S. neurona in North America, are an introduced species in California. S. neurona DNA isolated from sporocysts and/or infected tissues of 10 opossums, 6 horses, 1 cat, 23 Southern sea otters, and 1 harbor porpoise (Phocoena phocoena) with natural infections was analyzed based on 15 genetic markers, including the first internal transcribed spacer (ITS-1) region; the 25/396 marker; S. neurona surface antigen genes (snSAGs) 2, 3, and 4; and 10 different microsatellites. Based on phylogenetic analysis, most of the S. neurona strains segregated into three genetically distinct groups. Additionally, fifteen S. neurona samples from opossums and several intermediate hosts, including sea otters and horses, were found to be genetically identical across all 15 genetic markers, indicating that fatal encephalitis in Southern sea otters and equine protozoal myeloencephalitis (EPM) in horses is strongly linked to S. neurona sporocysts shed by opossums.
(c) 2010 Elsevier B.V. All rights reserved.
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Publication Date: 2010-02-11 PubMed ID: 20226596PubMed Central: PMC4878691DOI: 10.1016/j.vetpar.2009.12.045Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The study investigates the characteristics of Sarcocystis neurona, a pathogen causing neurological diseases in horses and other animals, in different hosts. The study reveals fatal encephalitis in Southern sea otters and equine protozoal myeloencephalitis in horses strongly link to S. neurona sporocysts shed by opossums.

Objective of the Research

  • The main aim of this research was to understand the molecular characteristics of the Sarcocystis neurona strains in different host species. Scientists endeavored to determine any genetic difference among the S. neurona strains isolated from different hosts.

Methodology

  • The S. neurona DNA was isolated from the sporocysts and/or infected tissues of various host species. The hosts include 10 opossums, 6 horses, 1 cat, 23 Southern sea otters, and 1 harbor porpoise, all with natural infections.
  • A total of 15 genetic markers were analyzed, comprising the first internal transcribed spacer (ITS-1) region, the 25/396 marker, S. neurona surface antigen genes (snSAGs) 2, 3, and 4, and 10 different microsatellites.

Findings

  • The phylogenetic analysis led to the identification of three primary genetically distinct groups of S. neurona strains.
  • Interestingly, fifteen S. neurona samples derived from opossums and several intermediate hosts, like sea otters and horses, were found to be genetically identical across all 15 genetic markers.

Implications

  • This genetic similarity across the hosts indicates that fatal encephalitis in Southern sea otters and equine protozoal myeloencephalitis (EPM) in horses are most likely caused by S. neurona sporocysts shed by opossums.
  • This finding is significant for the implementation and development of control and treatment strategies against these diseases.
  • The study highlights the importance of addressing the ecological role of opossums in the spread and perpetuation of S. neurona in the environment.

Cite This Article

APA
Rejmanek D, Miller MA, Grigg ME, Crosbie PR, Conrad PA. (2010). Molecular characterization of Sarcocystis neurona strains from opossums (Didelphis virginiana) and intermediate hosts from Central California. Vet Parasitol, 170(1-2), 20-29. https://doi.org/10.1016/j.vetpar.2009.12.045

Publication

Veterinary parasitology
ISSN: 1873-2550
NlmUniqueID: 7602745
Country: Netherlands
Language: English
Volume: 170
Issue: 1-2
Pages: 20-29

Researcher Affiliations

Rejmanek, Daniel
  • Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. drejmanek@ucdavis.edu
Miller, Melissa A
    Grigg, Michael E
      Crosbie, Paul R
        Conrad, Patricia A

          MeSH Terms

          • Amino Acid Sequence
          • Animals
          • Antigens, Protozoan / chemistry
          • Antigens, Protozoan / genetics
          • Base Sequence
          • California / epidemiology
          • Conservation of Natural Resources
          • DNA, Protozoan / chemistry
          • DNA, Protozoan / genetics
          • DNA, Ribosomal Spacer / chemistry
          • DNA, Ribosomal Spacer / genetics
          • Microsatellite Repeats / genetics
          • Molecular Sequence Data
          • Opossums / parasitology
          • Otters / parasitology
          • Phylogeny
          • Polymerase Chain Reaction / veterinary
          • Polymorphism, Genetic / genetics
          • Sarcocystis / classification
          • Sarcocystis / genetics
          • Sarcocystis / isolation & purification
          • Sarcocystosis / epidemiology
          • Sarcocystosis / parasitology
          • Sarcocystosis / veterinary
          • Sequence Alignment
          • Sequence Analysis, DNA

          Grant Funding

          • Z01 AI001017-02 / Intramural NIH HHS

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