BIOAVAILABILITY OF FLUMEQUINE AFTER ORAL-ADMINISTRATION TO ATLANTIC SALMON (SALMO-SALAR L)

The bioavailability of flumequine was investigated in Atlantic salmon (Salmo salar L.) in seawater at 6-8 degrees C. Four types of commercia lly available medicated fish feed containing flumequine (5 g kg(-1)) w ere administered to different groups of salmons (dose: 25 mg kg(-1) bo dy weight). The drug was also given as an intravascular bolus injectio n (dose: 10 mg kg(-1) b.w.) and in form of a suspension in water, fish oil or corn oil (dose: 25 mg kg(-1) b.w.). Elimination half-lives of 30-40 h were found. The bioavailability of all the tested products was around 40%. Neither the absorption rate, the absorption pattern, nor the presence of feed seemed to have any influence on the bioavailabili ty. The in vitro flumequine release from the medicated feed pellets wa s tested using a flow-through apparatus as described in the European P harmacopoeia. A clear difference in dissolution profile among the four products was seen.