Goats are gaining popularity as companion animals and are increasingly used in investigative studies, so the need to anesthetize these animals to facilitate surgical treatment or research is increasing. Only a few reports1–3 describe induction of anesthesia in goats, but ketamine continues to be a mainstay in the anesthetic management of small ruminants because of its reasonable cost and wide margin of safety.4 However, challenges with intubation owing to large amounts of salivary and oral secretions, maintenance of reflexes, and inadequate muscle relaxation combined with the anatomic challenges of a small oral cavity opening and long soft palate are reported.5 For these reasons, large or repeated doses may be necessary to provide adequate conditions for intubation in this species.1,6 A delay in intubation or multiple unsuccessful attempts can predispose a patient to potential complications such as regurgitation and aspiration.1,6 In goats, as with other species, ketamine is therefore frequently combined with either propofol or a benzodiazepine in an effort to improve intubation conditions and reduce the required dose of ketamine.4,6,7
Alfaxalone, a neuroactive steroid anesthetic induction agent, has recently become available in the United States. It has been used to induce anesthesia in many veterinary species, including cats, dogs, sheep, horses, and pigs.8–12 Intravenous doses of 2 and 5 mg of alfaxalone/kg have resulted in anesthesia of unpremedicated dogs and cats, respectively.8,9 Results from a study3 of 6 mixed-breed goats indicate the anesthetic induction dose of alfaxalone is between 2 and 3 mg/kg, depending on the degree of sedation following preanesthetic medication. In that study,3 alfaxalone was administered at a dosage of 1.5 mg/kg, IV, over 30 seconds, followed by additional alfaxalone boluses of 0.5 mg/kg, IV, every 15 seconds as needed until swallowing reflexes were diminished and jaw tone was relaxed enough to allow for orotracheal intubation. The use of alfaxalone as a maintenance anesthetic in a population of indigenous African goats is also described.3,13,14 The purpose of the study reported here was to build on this limited prior information in a different population of goats and directly compare the traditional anesthetic agent ketamine with the newer anesthetic agent alfaxalone for induction of anesthesia in premedicated goats. The null hypothesis was that no differences in measured variables would be observed between goats that received ketamine and those that received alfaxalone.
No third-party funding or support was received in connection with this study or with the writing or publication of the manuscript. The authors declare that there were no conflicts of interest.
Published in abstract form in the Proceedings of the American College of Veterinary Anesthesia and Analgesia Annual Meeting, New Orleans, September 2018.
Diastolic arterial blood pressure
Mean arterial blood pressure
Systolic arterial blood pressure
Random integer generator. Randomness and Integrity Services Ltd, Dublin, Ireland. Available at: www.random.org/integers/. Accessed Dec 16, 2017.
West-Ward Pharmaceutical Corp, Eatontown, NJ.
Deltran, Utah Medical Products Inc, Midvale, Utah.
Alfaxan, Jurox Inc, Kansas City, Mo.
VetaKet, Akorn Animal Health, Lake Forest, Ill.
Piramal Critical Care Inc, Bethlehem, Pa.
Normosol R, Hospira Inc, Lake Forest, Ill.
SAS Proc Mixed, version 9.4, SAS Institute Inc, Cary, NC.
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