Presentation on theme: "Abundance of the polychaete host of Ceratomyxa shasta and prevalence of infection in the Klamath River. Sue-Jie Koo Mentors: Jerri Bartholomew Sascha Hallett."— Presentation transcript:
Abundance of the polychaete host of Ceratomyxa shasta and prevalence of infection in the Klamath River. Sue-Jie Koo Mentors: Jerri Bartholomew Sascha Hallett Department of Microbiology Oregon State University
Ceratomyxa shasta : The parasite A myxozoan parasite Ceratomyxosis – epithelial lining necrotises in salmonids. Enzootic to the Pacific NW of the United States. –Particularly prevalent in the Klamath River One of the primary causes of juvenile salmonid death in the Klamath River. 54% infected in 2008, compared to 10% in other rivers in the West. ~10 μm
Life cycle of C. shasta
Manayunkia speciosa : The polychaete Freshwater Definitive host in the lifecycle of C. shasta Few studies on its ecology Spatial distribution Seasonality Density Few studies on its role in the infection dynamics of C. shasta Prevalence of infection Intensity of infection Seasonality Spatial distribution
Working hypothesis Polychaete densities and infection prevalence with Ceratomyxa shasta directly correlate with disease effects in salmonids. +=
Significance Assist in parasite management options to reduce the impact of the parasite on salmonid populations in the Klamath River. Reduction in returns affect fishermen and farmers Contribute data to the information known about M. speciosa.
Methodology The samples were collected as part of a large sampling study in the Klamath River in R3 R2R1
Water samples Sentinel fish studies Beaver Creek R3R2R1
Av. # polychaetes x # squares Av. field sampling area Field density = Polychaete Density Stained Manayunkia speciosa
Results Beaver Creek R3R3 R2R2 R1R1
Prevalence of Infection Results – no parasite detection 630 bp
Troubleshooting DNA recovery Parasite spike was inhibited Change DNA extraction buffers and dilution 2006 Polychaete DNA not replicated in PCR Change extraction buffers, dilution, primers, PCR programs Diagnostics comparing 2006 and 2009 polychaetes Crude vs Qiagen purified Qiagen purified 2006 DNA inconsistent results
Conclusions Highest polychaete density in highly infectious zone correlates to preliminary studies.
Potential Future Work Manayunkia speciosa temporal distribution M. speciosa prevalence of infection with Ceratomyxa shasta
Acknowledgements Sascha Hallett Jerri Bartholomew Gerri Buckles Jill Pridgen Dan Horner Bartholomew Lab Salmon Disease Lab Oregon Department of Fish and Wildlife HHMI Kevin Ahern