A Comparative Study of Intramuscular Alfaxalone- or Ketamine-Based Anesthetic Mixtures in Gray Squirrels Undergoing Gonadectomy: Clinical and Physiologic Findings

Abstract

The gray squirrel is one of the most common invasive species in Europe, whose presence is dangerous for the survival of the European red squirrel. To cope with this biological invasion and to safeguard biodiversity, the LIFE+U-SAVEREDS project aims to protect the red squirrel, by limiting the growth of the current population of gray squirrels and simultaneously promoting their eradication with surgical sterilization. This study compares two different anesthetic protocols, including dexmedetomidine (40 µg/kg) and midazolam (0.3 mg/kg) associated with ketamine (15 mg/kg; n = 25 squirrels) or alfaxalone (5 mg/kg; n = 22 squirrels). A blinded investigator evaluated the quality and onset of sedation, intraoperative anesthesia, and recovery, as well as the physiologic parameters for each animal. Alfaxalone provided a good quality of anesthesia with limited cardiovascular effects (p < 0.05) and good intraoperative myorelaxation. Ketamine induced complete relaxation in a shorter time (p < 0.05) and a rapid (p < 0.001) and excellent (p < 0.05) recovery. Despite the overall superiority of ketamine, alfaxalone appeared to be an adequate alternative anesthetic drug that can be administered without requiring intravascular access. It should be rapidly metabolized and excreted; however, it requires the combination of longer acting sedatives/myorelaxants to prevent a poor recovery quality.

Gonadectomy in Raccoons: Anesthetic and Cardiorespiratory Effects of Two Ketamine-Based Pre-Anesthetic Protocols before Sevoflurane-Sufentanil

“…In veterinary medicine, the advantages of combining dexmedetomidine and ketamine have been related to the expected, rapid and smooth induction and maintenance of anesthesia. Dexmedetomidine provides excellent muscular relaxation and analgesia for surgical procedures, and the use of atipamezole offers rapid reversal of anesthetic effects leading to a fast recovery [ 19 , 27 , 29 ].…”

“…Time from injection to first manual approach was recorded (‘inj-approach’). Thereafter the animal was removed from the cage and the overall quality and the depth of anesthesia were assessed with a descriptive score scale (DSS) modified by Nannarone et al 2020 [ 19 ]. The DSS included depth of anesthesia, muscle relaxation and ease of cephalic catheterization ( Table 1 ).…”