Opportunistic Bacteria Isolated from Trypauchen Vagina Fish that Infected with Protozoan from Iraq Marine Water

Abstract

Opportunistic bacteria are microorganisms that have been isolated from a host suffering from stress as a result of parasitic infestation. In this study, two bacterial species, namely Aeromonas hydrophila and Rhizobium radiobacter, were isolated from Trypauchen vagina fish that were infected with Microsporidian parasite cysts from Iraqi marine waters. The infection were mass implanted in the internal and external skeletal muscles and under the gill cover. Many symptoms of bacterial infection were observed in the fish, including flatulence with haemorrhagic fluids, skin disscolouration blackening, separation of crusts, and deformities in the area. The two bacterial species were characterised morphologically and identified using Vitek II system (Biomerieux - USA). To control infection, antibiotic susceptibility was performed using six antibiotics: nalidixic acid, nitrofurantoin, gentamicin, streptomycin, tetracycline and amoxicillin, both bacteria showed high antibiotic resistance. Identification of opportunistic bacteria has a pivotal role in preventing stress factors in fish, treating infections and alleviating their impact on other aquatic organisms.