Comparative pharmacokinetics of intravenous and intramuscular cefquinome sulfate administration in ducklings and goslings

OBJECTIVE To compare the pharmacokinetics of cefquinome sulfate in ducklings and goslings after IV or IM administration of a single dose. ANIMALS 216 healthy Muscovy ducklings (Cairina moschata) and 216 healthy Sichuan white goslings (Anser cygnoides). PROCEDURES Ducklings and goslings were each randomly assigned to 3 groups (n = 72/group) that received a single dose (2 mg/kg) of injectable cefquinome sulfate administered IV or IM or of injectable cefquinome sulfate suspension administered IM. Blood samples were collected at various points after drug administration (n = 6 birds/time point). Plasma cefquinome concentrations were measured by high-performance liquid chromatography with UV detection, and pharmacokinetic parameters were calculated with a 2-compartment model method. RESULTS After IV injection, mean distribution half-life of cefquinome was longer in goslings (0.446 hours) than in ducklings (0.019 hours), whereas volume of distribution at steady state was greater (0.432 vs 0.042 L/kg) and elimination half-life was slower (1.737 vs 0.972 hours). After IM administration of injectable cefquinome sulfate, bioavailability of the drug was higher in goslings (113.9%) than in ducklings (67.5%). After IM administration of injectable cefquinome sulfate suspension, bioavailability was also higher in goslings (123.1%) than in ducklings (96.8%), whereas elimination half-life was slower (6.917 vs 1.895 hours, respectively). CONCLUSIONS AND CLINICAL RELEVANCE In goslings, IV administration of cefquinome resulted in slower distribution and metabolism of the drug than in ducklings and IM administration resulted in higher bioavailability. The delayed-release effect of the injectable cefquinome sulfate suspension when administered IM was observed only in goslings.