Plasma pharmacokinetic profile of fipronil 1% pour-on in goats

of 558.4 ± 92.1 ng day/mL. This is the first study to characterize the plasma pharmacokinetic profile of fipronil pour-on in goats. The observed systemic exposure in goats was substantially higher (over 800-fold) than previously reported for cattle, suggesting major species-specific differences in dermal absorption. The prolonged persistence and delayed metabolite formation are suggestive of- flip-flop kinetic pattern, likely governed by slow redistribution from skin and adipose reservoirs. These findings provide a preliminary pharmacokinetic background for future residue depletion studies and food safety assessments in goats.