Detection and Isolation of Aeromonas veronii and Staphylococcus lentus from Gill Lesion of Common Carp (Cyprinus carpio L.), Reared in Earthen Ponds

The presence of gill lesions in common carp represents a severe risk to aquaculture, leading to considerable economic losses for fish producers. More than one species of bacteria has the ability to co-infect a gill. In the current study, two opportunistic and multidrug resistant bacteria, which are Aeromonas veronii and Staphylococcus lentus were isolated from gills of morbid common carp and induced typical gill lesion. Fish suffered high mortality and histopathological changes in gill tissue were noticed. Vitek II system was used to identify the level of bacterial isolates and PCR detection bacterial spp. A subsequent sequencing of the PCR products, with phenotypic characteristics were used to analyze 16S rRNA gene sequences that were used to record the isolates in the GenBank database accession numbers of A. veronii strain OM2 was (PQ269177) and S. lentus strain OM6 was (PQ 269179). Based on the study outcomes, both bacterial species may be the causative agent of lesions in common carp in Sulaimaniya governorates of northern Iraq, were for the first time reported.