The effects of breed and routes of administration on the plasma pharmacokinetics and faecal excretion of robenacoxib in goats
Özet
Robenacoxib (RX) is a non-steroidal anti-inflammatory drug (NSAID) of the coxib class. This study aimed to
evaluate the plasma dispositions and faecal excretion profiles of RX in Alpine and Saanen goats following oral
and subcutaneous routes. Two different goat breeds were allocated into two treatment groups concerning the
breed. RX was administered subcutaneously to animals at a dose of 4 mg/kg b.w. Following a one-week washout
period, RX was administered by oral route to the same animals at the same dose. Heparinized blood samples were
collected from all animals before drug administration (0 h) and subsequently up to 24 h. Faecal samples were
collected at various times between 8 h and 36 h. The concentrations of RX in plasma and faeces were determined
by HPLC. The plasma half-life (T1/2λz) of RX in Saanen goats (1.21 h) was significantly longer (P < 0.017) than in
Alpine goats (0.90 h) after subcutaneous administration. In both goat breeds, statistical differences were
observed between subcutaneous and oral administration of RX for T1/2λz, Tlast, Cmax, AUC0-∞, and MRT0-∞. Faecal
Cmax and Tmax parameters following oral administrations were 0.92 µg/g and 0.85 µg/g at 30 h and at 24 h in
Alpine and Saanen goats, respectively. The difference in plasma protein ratio between Alpine and Saanen goats
may have affected the T1/2λz of the drug. NSAIDs are among the drug groups frequently detected in aquatic and
terrestrial ecosystems around the world and there are data on the effects of NSAID residues on wildlife and
aquatic species. Therefore, revealing the excretion of NSAIDs, which are frequently used in the veterinary field,
in faeces and urine should be considered for ecological sustainability.
