Group (3): 120 goldfish were administrated
orally with 10 mg kg-1 BW of norfloxacin once daily for 5 consecutive
days, to determine the blood concentrations of norfloxacin in healthy
fishes. Group (4): 120 goldfish were intraperitoneally injected with
Aeromonas hydrophilia. After the appearance of signs of infection as
hemorrhage all over the skin especially under the base of the fins and
erosion in fins, each fish was orally administrated with 10 mg kg-1
BW of norfloxacin once daily for 5 consecutive days, to determine
the blood concentrations of norfloxacin in infected fishes. Before
the experiment blood samples were taken, negative control samples
(non-treated) showed no bacterial inhibition, indicating no intrinsic
antibacterial activity of the samples. The experiment was performed
in accordance with the guidelines set by the Ethical Committee of
Benha University, Egypt.