Abstract

White-spotted bamboo sharks (Chiloscyllium plagiosum) and related species are a common set of elasmobranchs housed in zoos and aquaria. Medical concerns like conspecific trauma and bacterial infections commonly lead to the empirical use of antibiotic medications like ceftazidime, despite limited to no prior pharmacokinetic studies for these drugs in elasmobranchs. In order to ascertain this information, 36 white-spotted bamboo sharks were divided into six groups to investigate the pharmacokinetics of a single intramuscular dose of ceftazidime at 20 mg/kg. Blood samples were collected across the groups for plasma drug concentration at time points t=0, 30 minutes, and 1, 2, 4, 6, 12, 24, 48, 72, and 96 hours post-injection. Samples were analyzed by the Clinical Pharmacology Laboratory at the College of Veterinary Medicine of North Carolina State University using high-pressure liquid chromatography (HPLC) analysis for plasma drug concentration with methods previously used by this laboratory for other species. Results revealed that for at least 96 hours, all sharks in the study maintained plasma concentrations of ceftazidime above the minimum inhibitory concentration (MIC) of susceptible bacteria. The long elimination half time suggests that recommended dosing intervals may be extended beyond the commonly used three days to at least every 96 hours.

Acknowledgements

The authors would like to thank the veterinary technical and zoological support staff of SeaWorld San Diego for assistance with sampling for this study.

*Presenting author
+Student presenter