Pharmacokinetics of Marbofloxacin Following Oral Administration in Lactic Acid Pretreated Broiler Chickens

Background: It is hypothesized that feeding lactic acid as a feed additive has the potential to alter the pharmacokinetics of many antimicrobial drugs being used for the treatment of infectious disease in general and marbofloxacin in particular; leading to either increased or decreased efficiency. Hence, the present study was planned to explore the effects of lactic acid pre-treatment on the pharmacokinetics of marbofloxacin after oral administration in broiler chickens. Methods: The pharmacokinetics of marbofloxacin was investigated following single dose oral administration (5 mg/kg) in lactic acid pre-treated (8 gm/l each, oral, 10 days) broiler chickens. The plasma concentration of marbofloxacin was determined by ultra-high-performance liquid chromatography to workout pharmacokinetic profile of marbofloxacin using non compartment model. Result: The AUC (area under curve) of marbofloxacin declined from 14.70 ìg·h/mL to 6.16 ìg·h/mL after pre-treatment of lactic acid. Similarly, the average values of maximum plasma concentration (Cmax) of drug decreased from 2.11 ìg/mL to 0.98 ìg/mL and mean body clearance (ClB) increased from 0.47 L/h/kg to 1.03 L/h/kg. The average elimination half-lives (t½â) of marbofloxacin before and after pre-treatment with lactic acid were 4.89 h and 2.81 h, respectively. Furthermore, the investigation revealed alteration of pharmacokinetic parameters evident in lactic acid pre-treated broiler chickens (as compared to non pre-treated birds) requiring adjustment of dosage regimens.