Bioavailability ruminant species

For pigs and ruminant species, dosing is generally by intramuscular injection, with once-daily dosing schedules. For example, Anaddn et al. reported a bioavailability of 74.5% after intramuscular dosing of enrofloxacin (2.5 mg/kg) in pigs, and tissue residue concentrations of enrofloxacin and the ciprofloxacin metabolite (mg/kg) at 5 days were 0.03, 0.08 (fat), 0.06, 0.04 (kidney), 0.06,... 

Published data on the pharmacokinetics of ionophores are limited. Dowling reports high bioavailability in mono-gastric species and approximately 50% in ruminants. Most ionophores are metabolized extensively in the liver, forming many metabolites that are secreted in bile and excreted in feces. 

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