UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Comparison of coho salmon (Oncorhynchus kisutch) strains for bacterial disease resistance and activity of the non-specific immune system Roome, Jennifer Robyn


Genetic variation in disease resistance was investigated in two coho salmon (Oncorhynchus kisutch) strains, previously demonstrated to have significant differences in survival after challenge with the marine fish pathogen Vibrio anguillarum, and their reciprocal strain crosses. V. anguillarum and the freshwater fish pathogen Aeromonas salmonicida were used in the disease challenges conducted by immersion, injection and cohabitation with infected cohorts. Kidney and gill lysozyme activity, white blood cell counts and hemoglobin concentration were determined following V. anguillarum immersion challenge of the pure strains and the strain-crosses. Overall, disease resistance among the strains after challenge with the two bacterial pathogens, by all methods of disease challenge, was not significantly different. Significant differences among the strains in non-specific immune parameters both before and after bacterial infection were described. As well, a significant treatment effect in lysozyme activity demonstrated that the bacterial challenges stimulated the non-specific immune system. No significant advantage to disease resistance against either vibriosis or furunculosis is likely to be gained by crossing the Quinsam River and Robertson Creek strains of coho salmon. Further, the inter-strain crosses did not appear to have an increased activity of the nonspecific immune system relative to the parent strains.

Item Media

Item Citations and Data


For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.

Usage Statistics