Llamas (Lama glama) are New World camelids native to South America and are considered to be at an intermediate evolutionary stage between guanacos and alpacas. In South America, llamas reside at altitudes between 0 and 4,500 m.1 Llamas have become increasingly popular in North America, and many surgical procedures performed on these animals necessitate that anesthesia be induced. Because of the unique anatomic features of llamas, jugular venipuncture is difficult, especially in adult males that have thick skin over the jugular furrow. Therefore, in many circumstances, IM administration of anesthetic drugs is a more practical route for delivery. Combinations of xylazine hydrochloride and ketamine hydrochloride are typically used to anesthetize llamas, but at the doses that are commonly administered, such combinations provide anesthesia for only a short duration.2
Tiletamine, a noncompetitive N-methyl–d-aspartate antagonist, and zolazepam, a benzodiazepine, are combined in an anesthetic preparation, which is available commerciallya as a 1:1 tiletamine-zolazepam formula that is used in many animal species. In llamas, administration of tiletamine-zolazepam (2 mg/kg, IM) induces only a brief period of antinociception3; however, increasing the dose of tiletamine-zolazepam does not increase the duration of antinociception (authors' unpublished observations) and has been associated with adverse effects.b Concurrent administration of xylazine, an α2-adrenergic receptor agonist that has sedative and analgesic properties, increases the antinociceptive effects of tiletamine-zolazepam in rats,4 and this combination has been used successfully to anesthetize wild5 and domesticated6 ruminants.
The purpose of the study reported here was to evaluate the antinociceptive and selected physiologic effects associated with IM administration of xylazine hydrochloride in combination with tiletamine-zolazepam in llamas. It was hypothesized that tiletamine-zolazepam would induce antinociception of short duration and that concurrent administration of xylazine would increase the duration of antinociception in a dose-dependent manner.
Diastolic arterial blood pressure
Mean arterial blood pressure
Oxygen saturation as measured by pulse oximetry
Telazol, Fort Dodge Animal Health, New York, NY.
Klein L, Tomasic M, Olson K. Evaluation of telazol in llamas (abstr), in Proceedings. Annu Meet Am Coll Vet Anesth 1989;23.
AnaSed, 100 mg/mL, Alkorn, Decatur, Ill.
1100 Patient Monitor, Criticare Systems, Waukesha, Wis.
Dinamap Veterinary Blood Pressure Monitor 8300, Critikon, Tampa, Fla.
i-STAT Portable clinical analyzer, Heska Corp, Loveland, Colo.
Nellcor N-20V pulse oximeter, Nellcor, Pleasanton, Calif.
Miltex, Lake Success, NY.
SAS, version 9.1, SAS Institute Inc, Cary, NC.
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