The objectives of this study were to determine the pathogenicity of a strain of Yersinia ruckeri, from an outbreak of yersiniosis in Huaraz and to characterize histopathological lesions in various organs of rainbow trout fingerlings (Oncorhynchus mykiss). One hundred fingerlings with an average weight of 7.25 g were used, divided into 5 groups of 20 individuals (four experimental and one control), kept in 30 L ponds. Experimental groups were inoculated via i.m. with 0.1 ml of the bacterial strain in concentrations of 1x104/ml (G1), 4x104/ml (G2), 1x108/ml (G3) and 4x108/ml (G4), and the control group with PBS. Clinical signs, external and internal lesions, morbidity and mortality were recorded for 12 days post-inoculation. Samples of liver, intestine, spleen, kidney, muscle and gills were collected for histopathological analysis. All fish inoculated with Y. ruckeri showed signs and lesio...

The objectives of this study were to determine the pathogenicity of a strain of Yersinia ruckeri, from an outbreak of yersiniosis in Huaraz and to characterize histopathological lesions in various organs of rainbow trout fingerlings (Oncorhynchus mykiss). One hundred fingerlings with an average weight of 7.25 g were used, divided into 5 groups of 20 individuals (four experimental and one control), kept in 30 L ponds. Experimental groups were inoculated via i.m. with 0.1 ml of the bacterial strain in concentrations of 1x104/ml (G1), 4x104/ml (G2), 1x108/ml (G3) and 4x108/ml (G4), and the control group with PBS. Clinical signs, external and internal lesions, morbidity and mortality were recorded for 12 days post-inoculation. Samples of liver, intestine, spleen, kidney, muscle and gills were collected for histopathological analysis. All fish inoculated with Y. ruckeri showed signs and lesio...