Lack of Protection following Re-Exposure of Chinook Salmon to Ceratonova shasta (Myxozoa)

Public Deposited

Downloadable Content

Download PDF


Attribute NameValues
  • The recent identification of multiple genotypes of the salmonid parasite Ceratonova shasta with different virulence levels in Chinook salmon (Oncorhynchus tshawytscha) suggests that it may be possible to immunize fish against subsequent infection and disease. We hypothesized that exposure of Chinook salmon to the less virulent parasite genotype (II) prior to the more virulent parasite genotype (I) would decrease disease and/or result in fewer mature parasites compared to fish only infected with the more virulent genotype. To test this, fish were challenged in a combination of field and laboratory exposures and we measured infection prevalence, percent morbidity, and mature parasite production. Neither mortality nor mature parasite production were reduced when fish were exposed to genotype II prior to genotype I as compared with fish exposed only to genotype I, suggesting that protection using a less virulent parasite genotype does not occur.
Resource Type
Date Available
Date Issued
  • Hurst, C. N., & Bartholomew, J. L. (2015). Lack of Protection following Re-Exposure of Chinook Salmon to Ceratonova shasta (Myxozoa). Journal of Aquatic Animal Health, 27(1), 20-24. doi:10.1080/08997659.2014.970716
Journal Title
Journal Volume
  • 27
Journal Issue/Number
  • 1
Academic Affiliation
Rights Statement
Funding Statement (additional comments about funding)
  • This work was funded by the Hatfield Marine Science Center William Q. Wick Marine Fisheries Award, the Flyfisher’s Club of Oregon and NOAA’s Graduate Sciences Program.
Peer Reviewed