Lower Red River and Lake Winnipeg South Basin Pathogen - Parasite Survey Report, Fall 2006
Freshwater Institute, Department of Fisheries and Oceans, Winnipeg, MB
Summary • 10 species of fish were targeted for collection, 60 fish per species were to be collected. • 9 ofthe 10 targeted species were successfully sampled. Only 7 channel catfish were captured. Total of 547 fish were screened for bacterial and viral pathogens of concern. • 60 lake whitefish were tested for the presence of Myxobolus cerebralis (causative agent of whirling disease). • There was no clinical evidence of disease suggestive of an infection with any bacterial and viral pathogens of concern in any of the fish examined. Lymphocystis and dermal sarcoma, both neoplasias having viral etiologies were observed in a small number of walleye and sauger. • Virus was not isolated from any of the samples received, nor were any bacterial pathogens of concern (e.g. Aeromonas salmonicida, causative agent offurunculosis, and Yersinia ruckeri, causative agent of enteric redmouth disease). • Myxobolus cerebralis was not detected in the lake whitefish sample. • The Winnipeg Fish Health Laboratory used the indirect fluorescent antibody technique to stain kidney smears to screen for the prescence of Rellibacterium salmollillarum (causative agent for bacterial kidney disease). The pathogen was not detected by this method in either the samples processed in the Winnipeg Fish Health Laboratory, nor the stained slide preparations received from the Bozeman Fish Health Center. The inter-laboratory exchange of material was undertaken to compare the results obtained in the two laboratories because distinctly different methods of detection for this pathogen were used in the respective laboratories.
Fish Pathology, Fish Parasite, Lower Red River, Lake Winnipeg, South Basin, Channel catfish, Emerald shiner, Fathead minnow, Yellow perch, White bass, Walleye, Northern Pike, Brook stickleback, Sauger, Goldeye