108 AJVR, Vol 69, No. 1, January 2008 O rthopedic problems are common in swine. In Scan- dinavia, the incidence of lameness is reported to be approximately 10% in young pigs, 1,2 with a preva- lence of 8.8% in loose-housed adult swine. 3 In Austra- lia, fibrinopurulent inflammation is a common find- ing in lame pigs < 6 weeks old, 4 whereas in Denmark, suppurative arthritis is less common in older lame pigs (3 to 5 months old). 5 In Finland, the most commonly diagnosed clinical condition in lame sows and gilts is osteochondrosis or osteoarthrosis. 3 In Denmark, mac- roscopic osteochondrotic lesions have been detected at slaughter in 47% of pigs with a history of lameness Evaluation of bioequivalence after oral, intramuscular, and intravenous administration of racemic ketoprofen in pigs Marja R. Raekallio, DVM, PhD; Katja M. Mustonen, DVM; Mari L. Heinonen, DVM, PhD; Olli A. T. Peltoniemi, DVM, PhD; Mia S. Säkkinen, PhD; S. Marikki Peltoniemi, PhD; Juhana M. Honkavaara, DVM; Outi M. Vainio, DVM, PhD Objective—To assess bioequivalence after oral, IM, and IV administration of racemic keto- profen in pigs and to investigate the bioavailability after oral and IM administration. Animals—8 crossbred pigs. Procedures—Each pig received 4 treatments in a randomized crossover design, with a 6- day washout period. Ketoprofen was administered at 3 and 6 mg/kg, PO; 3 mg/kg, IM; and 3 mg/kg, IV. Plasma ketoprofen concentrations were measured by use of high-performance liquid chromatography for up to 48 hours. To assess bioequivalence, a 90% confidence in- terval was calculated for the area under the time-concentration curve (AUC) and maximum plasma concentration (C max ). Results—Equivalence was not detected in the AUCs among the various routes of admin- istration nor in C max between oral and IM administration of 3 mg/kg. The bioavailability of ketoprofen was almost complete after each oral or IM administration. Mean ± SD C max was 5.09 ± 1.41 µg/mL and 7.62 ± 1.22 µg/mL after oral and IM doses of 3 mg/kg, respectively. Mean elimination half-life varied from 3.52 ± 0.90 hours after oral administration of 3 mg/kg to 2.66 ± 0.50 hours after IV administration. Time to peak C max after administration of all treatments was approximately 1 hour. Increases in AUC and C max were proportional when the orally administered dose was increased from 3 to 6 mg/kg. Conclusions and Clinical Relevance—Orally administered ketoprofen was absorbed well in pigs, although bioequivalence with IM administration of ketoprofen was not detected. Orally administered ketoprofen may have potential for use in treating pigs. (Am J Vet Res 2008;69:108–113) and 35% of pigs without a history of lameness. 5 Clini- cal lameness induces an acute-phase reaction in adult swine 3 and finishing pigs. 6 An injection of meloxicam can reportedly 7 alleviate lameness and improve feed intake in pigs with noninfectious locomotor disorders. Alleviation of pain is probably also beneficial when used in combination with administration of antimicro- bials to treat pigs with joint infections. A need exists Received February 6, 2007. Accepted June 11, 2007. From the Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, PO Box 57, University of Helsinki, Fl-00014 Helsinki, Finland (Raekallio, Honkavaara, Vainio); Vetcare Ltd, PO Box 99, FI-24101 Salo, Finland (Mustonen); and the Division of Biopharmaceutics and Pharmacokinetics, Faculty of Pharmacy, (Säkkinen, SM Peltoniemi) and the Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, FI- 04920 Saarentaus, Finland (Heinonen, OAT Peltoniemi). Supported by Vetcare Limited. The authors thank Katri Koski and Erja Piitulainen for assistance with high-performance liquid chromatography assays and Elina Viitasaari and Laura Malinen for assistance with collection and preparation of blood samples. Address correspondence to Dr. Raekallio. ABBREVIATIONS NSAID Nonsteroidal anti-inflammatory drug HPLC High-performance liquid chromatography AUC Area under the time-concentration curve AUC 0–12 Area under the time-concentration curve from time 0 to 12 hours AUC 0–∞฀ Area under the time-concentration curve from time 0 to infinity C max Maximum plasma concentration T max Time to maximum plasma concentration t ½ Elimination half-life β฀ Rate constant of the elimination phase V d Volume of distribution CL Total clearance MRT Mean residence time MAT Mean absorption time CI Confidence interval Unauthenticated | Downloaded 02/27/23 07:38 AM UTC