Uney, KamilCorum, OrhanCorum, Duygu DurnaCoskun, DevranSakin, FatihElmas, Muammer2024-12-242024-12-2420240140-77831365-2885https://doi.org/10.1111/jvp.13481https://hdl.handle.net/20.500.12604/7153Flunixin's pharmacokinetics, bioavailability, and plasma protein binding were examined in rainbow trout. The experiment involved 252 rainbow trout (Oncorhynchus mykiss) maintained at 12 +/- 0.6 degrees C. Flunixin was administered to rainbow trout via intravascular (IV), intramuscular (IM), and oral routes at a dosage of 2.2 mg/kg. Plasma samples were collected at times 0 (control), 0.25, 0.5, 1, 2, 4, 6, 8, 10, 12, 24, 48, 72, and 96 h. High-pressure liquid chromatography-ultraviolet was employed to quantify flunixin concentrations. The elimination half-life (t(1/2 lambda z)) for flunixin was 8.37 h for IV, 8.68 h for IM, and 8.76 h for oral. The t(1/2 lambda z) was similar between administration groups. The volume of distribution at a steady state and total body clearance were 55.81 mL/kg and 6.83 mL/h/kg, respectively, after IV administration. The mean peak plasma concentration was 6.24 +/- 0.41 mu g/mL at 4 h for oral administration and 13.98 +/- 0.86 mu g/mL at 2 h for IM administration. The in vitro protein binding ratio of flunixin in rainbow trout plasma was 96.34 +/- 2.29%. The bioavailability of flunixin after oral (25.74%) administration was lower than that after IM (66.70%) administration. Thus, developing an oral pharmaceutical formulation that can be administered with feed and has high bioavailability could enhance the therapeutic effect.eninfo:eu-repo/semantics/closedAccessbioavailabilityflunixinpharmacokineticsplasma protein bindingrainbow troutArticleN/AWOS:001313623300001Q12-s2.0-852040656033927927510.1111/jvp.13481