Anesthetic Effects of Intravenous Tiletamine-Zolazepam Injections in Bamboo Sharks
Abstract
The anesthetic effects of intravenous tiletamine-zolazepam (Telazol®) were evaluated in both white-spotted bamboo sharks (Chiloscyllium plagiosum) and brown-banded bamboo sharks (Chiloscyllium punctatum). The purpose of this study was to evaluate Telazol® as an alternative to tricaine methanesulfonate (MS-222) or propofol for the immobilization of sharks.1,2 Previous reports of intramuscular administration of Telazol® in other shark species resulted in excitability.3 In this study, Telazol® (50 mg/mL) was administered via the ventral tail vein at 5, 10, 15, and 20 mg/kg to two adult bamboo sharks (mean weight 2.03 kg ± SD 0.47) at each dose. Respiratory rate, loss of righting reflex, ventilatory reflex when removed from the water, and pain response (fin pinch) were evaluated at 5-minute intervals and used to determine the depth of anesthesia. Differences in response based on sex and species were not evaluated. Although increasing doses of Telazol® resulted in increased periods of sedation, anesthetic response to the drug was varied even in sharks that received the same dose. Increasing doses also increased the duration of apnea post-administration, requiring assisted ventilation to avoid hypoxia, hypercarbia, and acidosis. Telazol® administered intravenously at 15 mg/kg provided complete immobilization within 15 minutes lasting up to an hour with the least amount respiratory depression. However, the variability in anesthetic depth between individuals receiving the same dose and prolonged apnea make Telazol® a less desirable anesthetic for immobilization than MS-222 or propofol.
Acknowledgements
The authors wish to thank the husbandry staff at the Aquarium of the Pacific for the care of the animals used in this study.
* Presenting author
Literature Cited
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