iajabmsIAJABMSIAJABMS2709-3298https://doi.org/10.47310/iajabms.2022.v03i01.015Microbiological Identification for Aeromonas Veronii and Its Experimental Pathogenesis of Necropsy Findings In RatsMustafaMohammedRadhiSabaaHilalHadiThikraAdnanJawadDepartment of Microbiology, College of Veterinary Medicine, Al-Qasim green University, IraqDepartment of Microbiology, College of Sciences, Al-Qasim green University, IraqThis study aimed to the identification of Fifty isolates of Iraqi Carp fish (Cyprinus carpio) collected from the ponds and farms in different locations of Karbala governorate during the summer of 2021 from June to September. Biochemical identification was completed by using the VITEK 2 compact system, depending on several biochemical and physiological test responses. Six groups of rats (6 rats per group) were used to determine the lethal dose of 50 (LD50). All rats infected (virulent) group were injected with (8.4 ⤫ 108 CFU/ml) of virulent Aeromonas veronii. The pathogenesis study showed a significant increase in the experimental (Virulent) group compared with the control group. All rats in the Virulent group suffered from severe clinical signs of diseases and died within 3-4 days. Post mortem examination & bacterial isolation after injection it general congestion and hyperemia of multiple organs, the small intestine mildly congested and hemorrhagic areas, Organs collected were culturally positive for A. vironii.