Estimulación de la fagocitosis en juveniles de Oncorhynchus mykiss inmunizados con fracciones de membrana externa de una cepa nativa de Flavobacterium psychrophilum

The aim of this study was to evaluate phagocytosis stimulation in Oncorhynchus mykiss (rainbow trout) juveniles immunized with outer membrane fraction (OMF) from Flavobacterium psychrophilum USM-3 native strain and challenged with Flavobacterium psychrophilum 1947^T standard strain. Fifteen specimens were immunized intraperitoneally with 10 μg of OMF and fifteen specimens with 0.1ml of bidistilled water. Afterwards, both groups were challenged with Flavobacterium psychrophilum 1947^T standard strain. After 21 days from first immunization, phagocytic activity and index were determined. Mean phagocytic activity in immunized fish was 22.4% mean while in control group it was 0.5% (p<0.05). Phagocytic index percentage in immunized fish and control group was 32.5% and 0.5% (p<0.05) respectively. It was concluded that outer membrane fraction from Flavobacterium psychrophilum USM-3 native strain stimulates phagocytosis in Oncorhynchus mykiss juveniles infected with F. psychrophilum 1947^T.