Pharmacokinetic Behavior of Enrofloxacin in Estuarine Crocodile (Crocodylus porosus) after Single Intravenous, Intramuscular, and Oral Doses

Abstract

The disposition kinetics of enrofloxacin at a single dose of 5 mg/kg body weight were determined in clinically healthy captive-reared estuarine crocodiles (Crocodylus porosus) after intravenous (i.v.), intramuscular (i.m.), and oral (p.o.) administration. Enrofloxacin plasma concentrations were determined by diode array detection-high-performance liquid chromatography (limit of detection/limit of quantitation: 0.05 microg/ml). Data were subjected to noncompartmental analysis. The integrated pharmacokinetic-pharmacodynamic (PK-PD) variables showed that optimal area under the curve from the time of dosing to 24 hr:minimal inhibitory concentration (MIC) (>125) and peak plasma concentrations:MIC (>8) ratios, as reported for concentration-dependent bactericidal antimicrobials like fluoroquinolones, were achievable with both a single i.v. or i.m. dose for susceptible microorganisms with MIC values of < or =0.5 microg/ml, while the relatively slow onset of peak time allowed an effective plasma drug level only on day 3. The persistence of useful plasma concentrations indicated the possibility of redosing every 3 day for parenteral routes of administration, while further studies are needed for the oral route. Nevertheless, the absence of adverse reactions in the animals following i.v., i.m., or p.o. administration of enrofloxacin after a single dose of 5 mg/kg indicates the possibility of its safe and effective clinical use in captive estuarine crocodiles.

Pharmacokinetics of marbofloxacin in freshwater crocodiles (Crocodylus siamensis) after intravenous and intramuscular administration

“…This finding fits well with those for enrofloxacin, another veterinary fluoroquinolone that has shown similar overall pharmacokinetic behavior to MBF in crocodiles. Indeed, it has been characterized by rapid absorption with an almost complete bioavailability and a prolonged elimination half‐life in American alligators (Helmick et al ., ) and in Crocodylus porosus (Martelli et al ., ).…”

Population pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin in clinically diseased or injured Eastern box turtles (Terrapene carolina carolina), yellow‐bellied sliders (Trachemys scripta scripta), and river cooters (Pseudemys concinna)

“…tiles (Papich, 2018). The pharmacokinetics of fluoroquinolones in chelonians, crocodilians, lizards, and snakes have varied by route and dose (Coke, Isaza, Koch, Pellerin, & Hunter, 2006;Corum et al, 2019;Giorgi et al, 2013;Lai et al, 2019Lai et al, , 2009Marín et al, 2008;Martelli et al, 2009;Poapolathep et al, 2020;Prezant, Isaza, & Jacobson, 1994;Salvadori et al, 2016;Spöle, Göbel, & Schildger, 1991;Young, Schumacher, Papich, & Jacobson, 1997). Enrofloxacin, the fluoroquinolone selected for study here, has potent antibacterial activity and is also metabolized in some animals to the active metabolite ciprofloxacin (Helmick, Papich, Vliet, Bennett, & Jacobson, 2004;Raphael, Papich, & Cook, 1994;Waxman et al, 2014).…”

Pharmacokinetics of marbofloxacin in Green sea turtles (Chelonia mydas) following intravenous and intramuscular administration at two dosage rates

“…To date, the information about dosage regimen of fluoroquinolone is available in some reptiles (Corum et al, 2019;Martelli et al, 2009;Salvadori, De Vito, Owen, & Giorgi, 2015); however, limited information about of marbofloxacin dosage regimen is available in sea turtles, C. Mydas. The different physiology and metabolism of reptiles make dosage extrapolation from mammalian studies questionable (Hunter & Isaza, 2008).…”