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• 1. [Article] Using Cure Models for Analyzing the Influence of Pathogens on Salmon Survival

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Taylor ...

  Citation × Citation Citation Abstract Copy Title: Using Cure Models for Analyzing the Influence of Pathogens on Salmon Survival Author: Som, Nicholas A., Bartholomew, Jerri L., Ray, R. Adam, Perry, Russell W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/utaf20/current#.U3ObohC88tU. Title: Using Cure Models for Analyzing the Influence of Pathogens on Salmon Survival Author: Som, Nicholas A., Bartholomew, Jerri L., Ray, R. Adam, Perry, Russell W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/utaf20/current#.U3ObohC88tU. Close

• 2. [Article] Mortality threshold for juvenile Chinook salmon (Oncorhynchus tshawytscha) in an epidemiological model of Ceratomyxa shasta

  The myxozoan parasite, Ceratomyxa shasta, is the most significant pathogen of juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Klamath River, CA, USA. This parasite requires two hosts - a freshwater ...

  Citation × Citation Citation Abstract Copy Title: Mortality threshold for juvenile Chinook salmon (Oncorhynchus tshawytscha) in an epidemiological model of Ceratomyxa shasta Author: Ray, R. Adam The myxozoan parasite, Ceratomyxa shasta, is the most significant pathogen of juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Klamath River, CA, USA. This parasite requires two hosts - a freshwater polychaete (Manayunkia speciosa) and a salmonid - to complete its life cycle. The complex life cycle and large geographic area where infection occurs make monitoring and managing the disease, ceratomyxosis, difficult. Epidemiological models are helpful tools to examine complex disease systems as they serve to identify parameters and rank their relative importance. A system of equations is used to derive the basic reproductive number (Ro) of the parasite. In this paper we present a model for ceratomyxosis induced mortality in Chinook salmon. The field experiments described herein quantify the mortality threshold (a critical parameter in the model), by exposing native Chinook salmon to C. shasta in the Klamath River. The average percent mortality that resulted from this challenge ranged from 2.5% to 98.5% over an exposure dose of 4.4 - 612 x 106 parasites. This study identified a non-linear mortality threshold for Iron Gate Hatchery (IGH) Chinook salmon that ranged from 5.6 - 9.9 x 104 total parasites. Below this threshold no mortality occurs, yet above it mortality dramatically increases. This threshold provides a target to reduce parasitism in emigrating juvenile Chinook salmon. Title: Mortality threshold for juvenile Chinook salmon (Oncorhynchus tshawytscha) in an epidemiological model of Ceratomyxa shasta Author: Ray, R. Adam The myxozoan parasite, Ceratomyxa shasta, is the most significant pathogen of juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Klamath River, CA, USA. This parasite requires two hosts - a freshwater polychaete (Manayunkia speciosa) and a salmonid - to complete its life cycle. The complex life cycle and large geographic area where infection occurs make monitoring and managing the disease, ceratomyxosis, difficult. Epidemiological models are helpful tools to examine complex disease systems as they serve to identify parameters and rank their relative importance. A system of equations is used to derive the basic reproductive number (Ro) of the parasite. In this paper we present a model for ceratomyxosis induced mortality in Chinook salmon. The field experiments described herein quantify the mortality threshold (a critical parameter in the model), by exposing native Chinook salmon to C. shasta in the Klamath River. The average percent mortality that resulted from this challenge ranged from 2.5% to 98.5% over an exposure dose of 4.4 - 612 x 106 parasites. This study identified a non-linear mortality threshold for Iron Gate Hatchery (IGH) Chinook salmon that ranged from 5.6 - 9.9 x 104 total parasites. Below this threshold no mortality occurs, yet above it mortality dramatically increases. This threshold provides a target to reduce parasitism in emigrating juvenile Chinook salmon. Close

• 3. [Article] Relationship Between Temperature and Ceratomyxa shasta–Induced Mortality In Klamath River Salmonids

  This is the publisher’s final pdf. The published article is copyrighted by American Society of Parasitologists and can be found at: http://amsocparasit.org/.

  Citation × Citation Citation Abstract Copy Title: Relationship Between Temperature and Ceratomyxa shasta–Induced Mortality In Klamath River Salmonids Author: Bartholomew, Jerri L., Holt, Richard A., Ray, R. Adam This is the publisher’s final pdf. The published article is copyrighted by American Society of Parasitologists and can be found at: http://amsocparasit.org/. Title: Relationship Between Temperature and Ceratomyxa shasta–Induced Mortality In Klamath River Salmonids Author: Bartholomew, Jerri L., Holt, Richard A., Ray, R. Adam This is the publisher’s final pdf. The published article is copyrighted by American Society of Parasitologists and can be found at: http://amsocparasit.org/. Close

• 4. [Article] Transmission and Persistence of Ceratomyxa shasta

  Celebration of Undergraduate Excellence (2013)

  Citation × Citation Citation Abstract Copy Title: Transmission and Persistence of Ceratomyxa shasta Author: Bartholomew, Jerri L., Ray, R. Adam, Wong, Peter, Hurst, Charlene N. Celebration of Undergraduate Excellence (2013) Title: Transmission and Persistence of Ceratomyxa shasta Author: Bartholomew, Jerri L., Ray, R. Adam, Wong, Peter, Hurst, Charlene N. Celebration of Undergraduate Excellence (2013) Close

• 5. [Article] Density of the Waterborne Parasite Ceratomyxa shasta and Its Biological Effects on Salmon

  This is the publisher’s final pdf. The published article is copyrighted by American Society for Microbiology and can be found at: http://www.asm.org/.

  Citation × Citation Citation Abstract Copy Title: Density of the Waterborne Parasite Ceratomyxa shasta and Its Biological Effects on Salmon Author: Bartholomew, Jerri L., Holt, Richard A., Ray, R. Adam, Atkinson, Stephen D., Buckles, Gerri R., Hallett, Sascha L., Hurst, Charlene N. This is the publisher’s final pdf. The published article is copyrighted by American Society for Microbiology and can be found at: http://www.asm.org/. Title: Density of the Waterborne Parasite Ceratomyxa shasta and Its Biological Effects on Salmon Author: Bartholomew, Jerri L., Holt, Richard A., Ray, R. Adam, Atkinson, Stephen D., Buckles, Gerri R., Hallett, Sascha L., Hurst, Charlene N. This is the publisher’s final pdf. The published article is copyrighted by American Society for Microbiology and can be found at: http://www.asm.org/. Close