Porcine Streptococcus Suis in Minnesota

the number of new water acres used for catfish production in the delta region of west-central Mississippi. This increase in production was reflected by the establishment of the fish health diagnostic laboratory at Belzoni in June 1986 and the subsequent increase in the aquatic diagnostic case load of the Mississippi Cooperative Extension Service. The fish health diagnostic laboratory case load has remained relatively constant since 1986, which may reflect a decreasing growth rate of this industry in Mississippi or failure of producers to seek diagnostic laboratory support. However, the industry continues to expand within Mississippi and in adjoining states and other areas of the country. Bacterial diseases continue to be a major economic factor for commercial catfish farmers. Motile Aeromonas septicemia, columnar-is disease (Cytophaga spp.), and enteric septicemia of catfish (E. ictaluri) were the most prevalent bacterial diseases identified. During epizootics, early and accurate disease diagnosis is critical to catfish producers to minimize losses. Affected fish frequently eat less and thus have limited exposure to antimicrobials. Therapeutic administration of antibiotics is expensive and too frequently is not cost effective. Therefore, prevention of diseases by minimizing stress and exposure to pathogens is the best management strategy. Acknowledgements. We acknowledge Dr. T. E. Wellbom for the development of, implementation of, and perseverance in maintaining the quality of this data base. T. E. Schwedler, Rachel H. Josey, and Virgie L. Freund were instrumental in maintaining collection and entry of these data. We thank Paula Rogers and Debbie Wright for assistance in preparation of this manuscript, which is submitted as publication #J-7773, Mississippi Agriculture and Forestry Experiment Station, Mississippi State, MS.