Efficacy of orally administered oxolinic acid and Vetoquinol, an oxolinic acid ester, for the treatment of furunculosis in Atlantic salmon Salmo salar held in seawater (original) (raw)
Related papers
Aquaculture, 2004
Plasma oxolinic acid (OXA) concentrations were measured in fish from a cage of farmed rainbow trout (Oncorhynchus mykiss) 1 day after the termination of medication. The fish were experiencing significant mortalities and following a diagnosis of vibriosis, OXA had been orally administered at 50 mg/kg for 6 days over a 9-day period. Samples from healthy fish (n = 20), moribund (n = 26) and dead fish (n = 10) were analysed by HPLC. There was a dramatic difference in the OXA concentrations between healthy and moribund fish. In the moribund group, none of which showed signs of recent feeding, 85% of the fish had OXA levels below the LOQ (0.005 mg/l). In contrast, 95% of the healthy fish had OXA concentrations >0.015 mg/l and the mean OXA concentration ( F standard deviation) was 0.156 F 0.152 mg/l.
Aquaculture, 2004
Concentrations of oxolinic acid (OXA) were measured in the plasma, muscle, liver, and kidney of 48 Atlantic salmons (Salmo salar) 1 day after the end of an oral administration. OXA was administered over a period of 13 days to control an outbreak of winter ulcer disease in a commercial marine farm. On the basis of their behaviour, the fish were classified as healthy (n = 18), moribund (n = 20), or dead (n = 10). There was a dramatic difference in the OXA concentrations in the healthy fish and those classified as moribund or dead. There was no evidence of bacterial infection in the 18 healthy fish, all of which were shown to be feeding. In these fish, the mean concentrations of OXA ( F standard deviation) in the plasma, muscle, liver, and kidney were 0.40 F 0.36 mg/l, 1.0 F 0.71 mg/kg, 0.93 F 0.67 mg/kg, and 1.13 F 0.87 mg/kg, respectively. Within the healthy group, there were considerable individual fish-to-fish variations in OXA concentrations and the mean coefficient of variation (CV) for the concentrations in the four tissues was 77%. In contrast, all 20 moribund fish showed external lesions and 19 showed signs of systemic infection. Only 2 showed signs of feeding, and the concentrations of OXA were below the limit of quantitation (LOQ) in 68%, 85%, 70%, and 80% of the plasma, muscle, liver, and kidney, respectively. These data suggest that the major 0044-8486/$ -see front matter D Aquaculture 238 (2004) 51 -66 function of the therapy was to assist healthy fish to resist de novo infection and that moribund fish had gained little or no benefit from the oral administration of OXA.
Frontiers in Veterinary Science
This study examined the uptake, tissue distribution and elimination of the antibacterial agents oxolinic acid and flumequine in lumpfish (Cyclopterus lumpus L.) by use of LC-MS/MS following a single oral administration of 25 mg/kg fish given in feed. Lumpfish are increasingly used as cleaner fish for removal of sea lice on commercially farmed salmon. The production of lumpfish is successful, but there are challenges with bacterial infections and the number of antibacterial treatments has increased in recent years. As the lumpfish is a novel species to farming, there is a need for pharmacokinetic data and establishment of protocols for efficient antibacterial treatment. The current study describes the pharmacokinetic properties of oxolinic acid and flumequine in lumpfish. Absorption of oxolinic acid was moderate and was characterized by a calculated peak plasma concentration (C max) of 2.12 µg/ml after 10.3 h (T max) and an elimination half-life (t 1/2 β) of 21 h. Area under curve (AUC) and AUC from 0 to 24 h (AUC 0−24h) were calculated to be 60.9 and 34.0 h µg/ml, respectively. For flumequine, plasma C max was found to be 2.77 µg/ml after 7.7 h (T max) with t 1/2 β of 22 h. The area under the curve (AUC) and AUC from 0 to 24 h (AUC 0−24) were calculated as 104.3 and 50.3 h µg/ml, respectively. Corresponding C max values in muscle, liver, and head-kidney for oxolinic acid were 4.01, 3.04, and, 4.68 µg/g, respectively and T max of 11.1, 9.2, and 10.0 h, respectively. For flumequine, C max values of 4.16, 4.01, and 7.48 µg/g were obtained in muscle, liver, and head kidney, respectively, with corresponding T max values of 10.2, 10.3, and 6.0 h. Antimicrobial susceptibility values as determined by minimum inhibitory concentration (MIC) analyses against 28 isolates of Aeromonas salmonicida isolated from diseased lumpfish ranged from 0.06 to 15 µg/ml for oxolinic acid and 0.024 to 6.25 µg/ml for flumequine. Bimodal distributions in susceptibility to both oxolinic acid and flumequine were observed. The combination of pharmacokinetic properties and MIC data make possible calculation of efficient treatment doses, which are needed to improve the welfare of lumpfish and minimize development of antibiotic resistant bacteria.
Residues of oxolinic acid in wild fauna following medication in fish farms
Diseases of Aquatic Organisms, 1992
Dispersion of oxolinic acid and occurrence of Aerornonas salmonicida in wild fauna were studied in animals captured in the vicinity of 2 aquaculture facilities during and after medication with this drug. Consumption of antibacterial agents in aquaculture has reached a considerable level. The major part of the drugs used reach the environment, either directly due to excessive feeding and reduced appetite of the cultured fish, or indirectly after having passed through the fish. Some of the drugs entering the environment are taken up by exploitable wild fish, shellfish and crustaceans, resulting in concentrations far above those accepted in food for human consumption in Norway. The concentration of oxolinic acid in muscle and liver was highest In pelagic flsh like coalfish and mackerel. The mean concentration in muscle of all positive samples at the day of medication termination were 4.38 pg g-l and 0.42 pg g-' at 2 different farms. Maximum concentration of oxolinic acid in muscle samples was 12.51 pg g-' We found a simultaneous occurrence of oxolinic acid and the fish pathogenic bacterium A. salmonicida in the gut of both cultured and wild fish. This may lead to development and dispersion of resistant bacteria. Blue mussels Mytjlus edulis harvested at one of the farms contained an elevated level of bacteria resistant to oxolinic acid.