Aeromonas hydrophila is a Gram negative bacterium that widely distributed in aquatic environments and an opportunistic pathogen for fish, reptiles, amphibians and humans, which is capable of causing severe hemorrhagic septicemia and skin ulceration in aquatic animals. It was known that A. hydrophila caused motile Aeromonas septicemia (MAS. To overcome this problem, fish cultivators usually use chemical drugs or antibiotics. Antibiotics can be grouped based on chemical formula, spectrum of activity and mechanism of action. Its use must be based on the accuracy of disease diagnosis so that it has a positive effect on healing the disease. Antibiotics with the active ingredient enrofloxacin are antibiotics with bacteriocidal properties, this antibiotic can be used on Gram-negative and Gram-positive bacteria. The aim of this study was to evaluate the administration of enrofloxacin in the treatment of A. hydrophila infections in catfish (Clarias sp.).
An initial experiment showed that the LD50 dose obtained was 5.42 x 108 cfu/ml and then will be used in efficacy testing. The treatment’s fish feed were prepared by mixing enrofloxacin in feed and Feeding were 2 times a day for 5 days experiment. The experimental method consisted of three groups and three replications with each container using 30 fishes. Control negative groups were those without antibiotics, control positive were those with Aeromonas hydrophila innjection dan treatment groups were those with bacteria injection and with antibiotics. Efficacy testing was carried out by calculating the fish survival rate for 5 days and calculating the reduction in Aeromonas sp at 24, 72 and 120 hours after treatment.
The result showed that the fish survival rate in negative control groups were 98.9%, in positive control groups were 15,6% and in treatment groups were 57,8%. While the decreasing number of Aeromonas sp. were 90%. This indicates that administration of enrofloxacin in feed at a dose of 10 mg/kg biomass can reduce the mortality rate of catfish infected by Aeromonas hydrophila