Enrofloxacin-based therapy to prevent endometritis in embryo transfer mares

GONZALEZ, .; C, MORENO, L,; FUMUSO, E., .; CONFALONIERI, A.,; SPARO, M.,; SÁNCHEZ BRUNI, S

JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS

WILEY-BLACKWELL PUBLISHING, INC

Año: 2009

0140-7783

Enrofloxacin (EFX) is often used empirically to prevent uterine infections inmares in order to improve efficiency on Commercial Embryo Transfer Farms.This study investigated the uterine distribution of EFX and its metaboliteciprofloxacin (CFX) in mares and assessed the minimal inhibitory concentra-tions (MIC) of EFX against various common pathogens as a basis forestablishing a rational dosing schedule. Plasma and uterine pharmacokinetic(PK) studies were performed in two groups (n = 5) of healthy mares followingintravenous (i.v.) administration of EFX at either 2.5 and at 5 mg⁄ kgbodyweight. Plasma and endometrial tissue samples, taken before for up to48 h after treatment were analysed by Reverse Phase HPLC. MIC values forwild strains of Gram-negative (Escherichia coli, Pseudomonas aeruginosa) andGram-positive bacteria (b-haemolytic streptococci) ranged from 0.25–2 and1.5–3.0 lg ⁄ mL respectively. In terms of tissue distribution, the sum of theendometrial concentrations of the parent drug (EFX) and its active metabolite(CFX) (in terms of AUC), exceeded those in plasma by 249% and 941%following administration of EFX at 2.5 and 5 mg⁄ kg respectively. After i.v.treatment with EFX at 5 mg⁄ kg, endometrial concentrations of EFX and CFXabove the MIC value were detected for 36–48 and 22–43 h posttreatment forGram-negative and -positive isolates respectively. Concentrations above MICwere maintained for much shorter periods at the lower (2.5 mg⁄ kg) treatmentdose. Based on these results, a conventional dose (5 mg⁄ kg) of EFX givenprebreeding followed by two further doses at 36–48 h postbreeding areproposed as a rational strategy for using of EFX as a preventative therapyagainst a variety of common bacterial strains associated with equineendometriti