title: Reversible anaesthesia of free-ranging lions (Panthera leo) in Zimbabwe.
abstract: The combination of medetomidine-zolazepam-tiletamine with subsequent antagonism by atipamezole was evaluated for reversible anaesthesia of free-ranging lions (Panthera leo). Twenty-one anaesthetic events of 17 free-ranging lions (5 males and 12 females, body weight 105-211 kg) were studied in Zimbabwe. Medetomidine at 0.027-0.055 mg/kg (total dose 4-11 mg) and zolazepam-tiletamine at 0.38-1.32 mg/kg (total dose 50-275 mg) were administered i.m. by dart injection. The doses were gradually decreased to improve recovery. Respiratory and heart rates, rectal temperature and relative haemoglobin oxygen saturation (SpO2) were recorded every 15 min. Arterial blood samples were collected from 5 lions for analysis of blood gases and acid-base status. For anaesthetic reversal, atipamezole was administered i.m. at 2.5 or 5 times the medetomidine dose. Induction was smooth and all lions were anaesthetised with good muscle relaxation within 3.4-9.5 min after darting. The predictable working time was a minimum of 1 h and no additional drug doses were needed. Respiratory and heart rates and SpO2 were stable throughout anaesthesia, whereas rectal temperature changed significantly over time. Atipamezole at 2.5 times the medetomidine dose was sufficient for reversal and recoveries were smooth and calm in all lions independent of the atipamezole dose. First sign of recovery was observed 3-27 min after reversal. The animals were up walking 8-26 min after reversal when zolazepam-tiletamine doses < 1 mg/kg were used. In practice, a total dose of 6 mg medetomidine and 80 mg zolazepam-tiletamine and reversal with 15 mg atipamezole can be used for either sex of an adult or subadult lion. The drugs and doses used in this study provided a reliable, safe and reversible anaesthesia protocol for free-ranging lions.
authors.affiliation: Section of Anaesthesiology and Emergency and Critical Care, Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, PO Box 7018, SE-750 07 Uppsala, Sweden. asa_fahlman@hotmail.com
authors.forename: A
authors.initials: A
authors.lastname: Fahlman
authors.forename: A
authors.initials: A
authors.lastname: Loveridge
authors.forename: C
authors.initials: C
authors.lastname: Wenham
authors.forename: C
authors.initials: C
authors.lastname: Foggin
authors.forename: J M
authors.initials: JM
authors.lastname: Arnemo
authors.forename: G
authors.initials: G
authors.lastname: Nyman
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage*; D000758:Anesthesia / Q000379:methods / Q000662:veterinary*; D019162:Anesthetics, Combined / Q000008:administration & dosage*; D000778:Anesthetics, Dissociative / Q000008:administration & dosage; D000818:Animals; D000835:Animals, Wild; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D007093:Imidazoles / Q000008:administration & dosage; D007273:Injections, Intramuscular / Q000662:veterinary; D008045:Lions / Q000502:physiology*; D008297:Male; D020926:Medetomidine / Q000008:administration & dosage; D012119:Respiration / Q000187:drug effects; D013992:Tiletamine / Q000008:administration & dosage; D013997:Time Factors; D015030:Zimbabwe; D015041:Zolazepam / Q000008:administration & dosage
chemical_list: D000317:Adrenergic alpha-Antagonists; D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative; D006993:Hypnotics and Sedatives; D007093:Imidazoles; C050701:atipamezole; D013992:Tiletamine; D015041:Zolazepam; D020926:Medetomidine