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The current work was aimed to identify the aerolysin (aerA) and hemolysin (hlyA) genes of A. hydrophila isolates separated from Cyprinus carpio in a farm in Al-Diwaniyah City, Iraq. Fish samples with external lesions were collected and A. hydrophila was isolated and characterized using traditional cultivation and biochemical techniques. Later, a total of 26 bacterial isolates were subjected to the identification of aerA and hlyA genes by employing PCR method. The clinical signs of the disease were reddish head, anal, and fin bases while the rest of the body was pale. External ulcerative and hemorrhage spots were noticed. In the detection of the bacterial genes, 19 (73%) were positive isolates for aerA and 13 (50%) positive for hlyA genes. Aeromonas hydrophila isolates from common carp contain aerolysin and hemolysin genes that increase the pathological effects on the infected fish.


AerA hlyA Aquaculture Carp.

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MUSLEM, E. T., SABEEH, S. A., & JHEEL, W. abd alwahed. (2021). Detection of aerolysin and hemolysin genes in Aeromonas hydrophila isolates from in Al-Diwaniyah City, Iraq. Iranian Journal of Ichthyology, 8, 392–396.


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