Abstract
The present study investigate pathogencity of Flexibacter maritimus (Tenacibaculum maritimum) in Red Sea cultured Asian Sea bass, Lates calcalrifer fish with a trial for treatment and control using antibiotics florfenicol and oxytetracycline. Naturally infected fish Sea bass, Lates calcalrifer fish was stocked in circular cement and earthen ponds along Red Sea coast, Fisheries Research center, Jeddah belonged to Agricultural ministry Saudi Arabia. Large number of Asian Sea bass fish suffering from discoloration, deep ulceration on the body especially back region, erosions and hemorrhages at the base of fins. A total number 180 naturally infected Asian Sea bass fish were divided into three groups each 20 with three replicates 1st group infested non treated, 2nd group treated with florfenicol 10 mg/kg body weight of fish in diet for 10 days, 3rd group treated with long acting oxytetracycline 75 mg/kg body weight in diet for 10 days. Blood samples were taken at the end of every week for three weeks post treatment, mortality rate, cortisol concentration of serum and phagocytic index were recorded along 3 weeks post treatment. The study concluded that Flexibacter maritimus infection in Asian Sea bass fish should be diagnosed and treated as quick as possible using florfenicole to avoid fish mortalities and economical losses.