Abstract
The scientific literature on binturongs (Arctictis binturong) is sparse and there is very little information on anesthesia of binturongs or any other viverrids.1,3 Anesthetic combinations of medetomidine, butorphanol, and ketamine have been proven to allow quick, relatively safe, and reversible immobilization and anesthesia in other members of the order Carnivora.2,4 This study investigated the effects of two combinations of medetomidine, butorphanol, and ketamine in order to determine an effective anesthetic protocol for binturongs.
Thirty-four captive adult binturongs were anesthetized for physical examinations. The cardiopulmonary effects of two combinations of ketamine-medetomidine-butorphanol were compared. Animals were assigned to one of two groups by stratified randomization. Group HK/LM was administered a relatively high dose of ketamine (Ketaset, Fort Dodge Animal Health, Fort Dodge, IA, USA; 8 mg/kg), a low dose of medetomidine (Dormitor, Pfizer Animal Health, Exton, PA, USA; 0.02 mg/kg), and butorphanol (Torbugesic, Fort Dodge Animal Health, Fort Dodge, IA, USA; 0.4 mg/kg). Group LK/HM was administered a relatively low dose of ketamine (4 mg/kg), and a high dose of medetomidine (0.04 mg/kg) and butorphanol (0.4 mg/kg). The weight of each animal was estimated prior to injection. Animals were restrained with a net and hand-injected in the thigh muscles. Each animal was allowed 10–15 minutes for induction. If needed, supplemental drugs were administered following the allotted induction period.
After transportation to a central processing location, animals were weighed and monitoring equipment was attached. Temperature, heart rate, respiratory rate, arterial blood pressure, arterial oxygen saturation, and end-tidal CO2 were measured every 5 minutes for 45 minutes. Time of induction, time to head up, and time of recovery (time to standing) were also noted. After 45 minutes of monitoring, animals in the HK/LM group were given an IM injection of atipamezole at 0.1 mg/kg (Antisedan, Pfizer Animal Health, Exton, PA, USA) and animals in the LK/HM group were administered 0.2 mg/kg of atipamezole. When possible, a 30 ml blood sample was obtained for complete blood count, serum biochemistries, serum vitamin and mineral analysis, and steroid hormone analysis. Most blood samples were obtained from the jugular vein, but other venipuncture sites included the cephalic, femoral, saphenous, and tail veins.
Data sets were tested for normality using Shapiro and Wilk’s test. Data sets that were normally distributed are reported as means (± standard deviations) and were analyzed by repeated measure ANOVA. Data sets that were not normally distributed were analyzed using a Kruskal-Wallis Test and median values are reported. Animals weighed 16–32 kg. Individuals varied greatly in the response to the anesthetic combinations. Of the 34 binturongs anesthetized, six in each group required supplemental agents to achieve adequate anesthesia. Physiologic values for the remaining 22 animals were analyzed. Leaving the animals without any stimulation for 10–15 minutes after administration appeared to improve the quality of induction and anesthesia. Heart rates were significantly higher in the LK/HM group at all time points. There were no significant differences in arterial oxygen saturation and both groups had animals with values <90%. Values for mean arterial blood pressure were not significantly different between groups. Respiratory rates, end-tidal CO2 values, and body temperatures were similar between the two groups. Time to intubation was significantly less in the HK/LM group (5 minutes) than in the LK/HM group (10 minutes). However, time to head up and time to recovery were significantly longer in the HK/LM group (24 minutes and 38 minutes, respectively) than in the LK/HM group (6 minutes and 12 minutes, respectively).
Although the LK/HM animals had longer induction times, the substantially shorter recovery times made this the preferred combination of the two investigated. However, there was a considerable amount of variability, as well as mild-to-moderate hypoxemia, with both combinations. Ketamine-medetomidine-butorphanol combinations can be used effectively in binturongs, but other anesthetic combinations should be investigated in an effort to find a protocol that provides more consistent results in this challenging species.
Literature Cited
1. Gray, C.W., M. Bush, and C.C. Beck. 1974. Clinical experience using CI-744 in chemical restraint and anesthesia of exotic specimens. J Zoo Anim Med. 5:12–21.
2. Langan, J.N., J. Schumacher, C. Pollock, S.E. Orosz, M.P. Jones, and R.C. Harvey. 2000. Cardiopulmonary and anesthetic effect of medetomidine-ketamine-butorphanol and antagonism with atipamezole in servals (Felis serval). J Zoo Wildl Med. 31:329–334.
3. Schobert, E. 1987. Telazol® use in wild and exotic animals. Vet Med Sm Anim Clin. 82:1080–1088.
4. Sladky K.K., B.T. Kelly, M.R. Loomis, M.K. Stoskopf, and W.A. Horne. 2000. Cardiorespiratory effects of four alpha2-adrenoceptor agonist-ketamine combinations in captive red wolves. J Am Vet Med Assoc. 217:1366–1371.