Isolation and identification of bacteria from Coptodon zillii (Gervais, 1848) and study of some virulence factors in Al-Diwaniya River/middle of Iraq

This study was conceded to examining the occurrence of possible pathogenic species of bacterium in C. zillii in the Al-Diwaniya River. A total of 100 fishes of C. zillii, during the period (April) 2021 till (March) 2022. Bacteria were recognized using the VITEK 2 system and designated biochemical tests. Species were recognized with different percentages in C. zillii, P. luteola, S. thalpophilum, S. lentus, and A. sobria. Antimicrobial susceptibility test of 16 antimicrobials, which are (Ampicillin, piperacillin/tazobactam, amikacin, cefazolin, Ceftriaxone, Ertapenem, Gentamycin, cefoxitin, ciprofloxacin, imipenem, ceftazidime, levofloxacin, cifepime, tigecyclin, Nitrofuran, and trimethoprime- sulphamethoxazole) was recognized and studied for antimicrobial susceptibility test using the Vitek II system. The best antimicrobial susceptibility were ciprofloxacin (<= 0. 11μg/ ml), Imipenem (<= 0. 25, μg/ ml), when tested in vitro on P. luteola, S. thalpophilum, S. lentus, A. sobria, and Livofloxacin (<= 0. 22, <= 0. 20, <= 0. 25, <= 0. 21, μg/ ml), when examined in vitro on P. luteola, S. thalpophilum, S. lentus, A. sobria while, it was resistant to cefazolin ( > = 70, >= 70, > = 76, >= 68, μg/ ml), when examined in vitro on P. luteola, S. thalpophilum, S. lentus, A. sobria. Keywords: Coptodon. zillii bacteria Antibiotics, Iraq.