Single‐dose pharmacokinetics of flumequine in halibut (Hippoglossus hippoglossus) and turbot (Scophthalmus maximus)

Abstract

Flumequine was administered to halibut (Hippoglossus hippoglossus) and turbot (Scophthalmus maximus) intravenously (i.v.) and orally (p.o.) at a dose of 10 mg/ kg bodyweight, and as a bath-treatment at a dose of 10 mg/L water for 2 h, using identical experimental designs. The study was performed in seawater with a salinity of 3% and a temperature of 10.3+/-0.4 degrees C (halibut) and 18.0+/-0.3 degrees C (turbot). Pharmacokinetic modelling of the data showed that flumequine had quite similar pharmacokinetic properties in halibut and turbot. Following intravenous administration, the volumes of distribution at steady state (Vss) were 2.99 L/kg (halibut) and 3.75 L/kg (turbot). Plasma clearances (Cl) were 0.12 L/kg (halibut) and 0.17 L/h x kg (turbot) and the elimination half-lives (t(1/2lambdaz)) were calculated to be 32 h (halibut) and 34 h (turbot). Mean residence times (MRT) were 25.1 h (halibut) and 22.2 h (turbot). Following oral administration, the t(1/2lambdaz) were 43 h (halibut) and 42 h (turbot). Maximal plasma concentrations (tmax) were 1.4 mg/L (halibut) and 1.9 mg/L (turbot), and were observed 7 h post administration in both species. The oral bioavailabilities (F) were calculated to 56% (halibut) and 59% (turbot). Following bath administration maximal plasma concentrations were 0.08 mg/L (halibut) and 0.14 mg/ L (turbot), and were observed 0 h (halibut) and 3 h (turbot) after the end of the bath. The bioavailability in halibut following a 2-h bath treatment was 5%.

Pharmacokinetics and tissue behavior of enrofloxacin and its metabolite ciprofloxacin in turbot Scophthalmus maximus at two water temperatures

“…The reported 50.82% or 66.13% bioavailability of enrofl oxacin was much lower than that of quinolones in domestic animals (Hu and Feng, 1999;Zeng et al, 2003;Albarellos et al, 2005;Dimitrova et al, 2006). However, other quinolones in turbot were reported with lower bioavailabilities than the bioavailability of enrofl oxacin, such as a 27.90% bioavailability of oxolinic acid after 10 mg/kg at 16°C, and a 59% bioavailability of fl umequine after oral administration at 10 mg/kg at 18°C (Poher, 1998;Hansen and Horsberg, 1999).…”

Diseases, prophylaxis and treatment of the Atlantic halibut Hippoglossus hippoglossus: a review

“…Atlantic halibut with a mean weight of 89 ± 15 g, held in seawater at 10.3°C were dosed with flumequine by intravenous injection and via oral administration in feed (10 mg kg -1 ) (Hansen & Horsberg 1999). Bioavailability following oral administration was 56% and plasma t 1/2 β values were 32 and 43 h respectively, following i.v.…”

“…group reached a C max of 1.4 µg ml -1 at a T max of 7 h. The distribution volume was 2.99 l kg -1 . Employing bath treatment for 2 h and a concentration of 10 mg l -1 of flumequine in the bath, the mean plasma concentration was calculated to be 0.08 µg ml -1 and bioavailability to be 5% (Hansen & Horsberg 1999). The authors concluded that a higher concentration of the drug in the bath and a prolonged treatment regime are needed to obtain therapeutic concentrations.…”

Administration of the antibacterial agents flumequine and oxolinic acid to small turbot (Scophthalmus maximus L.) by bath

“…The quinolones flumequine and oxolinic acid have been used intensively to treat systemic bacterial infections like furunculosis, vibriosis and enteric redmouth disease in fish (Michel et al 1980; Austin et al 1983; Rodgers and Austin 1983; O'Grady et al 1988; Samuelsen 1997; Samuelsen et al 2000a). The widespread use of these drugs is mainly because of their relatively low minimum inhibitory concentrations (MIC) for the most susceptible fish pathogens (Martinsen 1993) and effective systemic distribution in fish (Chevalier et al 1981; Elema et al 1994; Martinsen and Horsberg 1995; Samuelsen and Ervik 1997; Hansen and Horsberg 1999, 2000; Samuelsen et al 2000b). The absorption and elimination of quinolones administered by bath in seawater has been previouly described for large (200 g) turbot, small (3–5 g) Atlantic halibut ( Hippoglossus hippoglossus L.), cod ( Gadus morhua L.), goldsinny wrasse ( Ctenolabrus rupestris L.) and corkwing wrasse ( Symphodus melops L.) (Samuelsen and Lunestad 1996; Hansen and Horsberg 1999, 2000; Samuelsen and Ervik 2001).…”

“…The widespread use of these drugs is mainly because of their relatively low minimum inhibitory concentrations (MIC) for the most susceptible fish pathogens (Martinsen 1993) and effective systemic distribution in fish (Chevalier et al 1981; Elema et al 1994; Martinsen and Horsberg 1995; Samuelsen and Ervik 1997; Hansen and Horsberg 1999, 2000; Samuelsen et al 2000b). The absorption and elimination of quinolones administered by bath in seawater has been previouly described for large (200 g) turbot, small (3–5 g) Atlantic halibut ( Hippoglossus hippoglossus L.), cod ( Gadus morhua L.), goldsinny wrasse ( Ctenolabrus rupestris L.) and corkwing wrasse ( Symphodus melops L.) (Samuelsen and Lunestad 1996; Hansen and Horsberg 1999, 2000; Samuelsen and Ervik 2001). Using a concentration of 10 mg L −1 of flumequine in the bath and a 2‐h treatment, the plasma concentrations achieved in turbot were low (0.14 μ g ml −1 ) (Hansen and Horsberg 1999).…”