Isolation of Aeromonas like bacteria from the grass carp (Ctenopharyngodon idella)

Abstract

In 1993, 66 live Grass carps, Ctenopharyngodon idella, were transferred to the laboratory of the Fisheries Research Center in Khouzestan Province. 42 of them were apparently healthy and the remaining 24 had the following symptoms Dark body coloration on posterior region, petechia on the mandibula, operculum, abdomen and pelvic fins, loss of the scales, inflammation around the anus, eye hemorrhages, hemorrhages in the anterior chamber of the operculum, petechia on the muscles, swelled intestine, occasionally with yellowish - white mucus, fin rot, pale gills and liver. The microbiological investigation and bacteria culture from the gills, kidney and liver of the apparently healthy fishes and the diseased fishes showed that some of the fishes in both groups were infected by the Aeromons-like bacteria. Some specimens of this species were isolated from the internal organs (kidney and liver) and the gills. This study revealed that such organisms may cause mortality in the Grass carp farms.