title: Chemical restraint of the Nile hippopotamus (Hippopotamus amphibius) in captivity.
abstract: This retrospective study describes 16 immobilizations performed on nine adult captive Nile hippopotamus (Hippopotamus amphibius). Animals were immobilized using intramuscular etorphine alone (1.0-5.0 micrograms/kg; n = 9) or in combination with xylazine (67-83 micrograms/kg; n = 6) or acepromazine (20 micrograms/kg; n = 1). Exact weights for the animals were unknown so drug dosages were based on estimated weights. Seven animals either were in good health or had minor or localized medical problems. Following etorphine and xylazine induction, one animal undergoing castration was anesthetized with isoflurane in oxygen delivered by endotracheal tube. Ten immobilizations occurred without complications, and eight of those procedures were rated as good or excellent. Complications, including bradypnea, cyanosis, and apnea, occurred during six immobilizations. One animal died following prolonged apnea, and the necropsy failed to find a specific cause of death. Immobilizations were reversed with diprenorphine alone (4.4-10.0 micrograms/kg; n = 13), diprenorphine (2.9 micrograms/kg) and naloxone (14.6 mu k/kg; n = 1), or naltrexone (146-180 micrograms/kg; n = 2). Mean time to reversal of immobilization for those animals given etorphine alone and reversed with diprenorphine alone was 21.6 min (n = 5). Time to reversal for the two immobilizations reversed with only naltrexone was 4 min. No renarcotizations were observed. Total doses of 2.0-6.0 mg etorphine i.m. should produce heavy sedation to surgical anesthesia in calm adult captive Nile hippopotamuses. Insufflation with oxygen during immobilization seems warranted.
authors.affiliation: Department of Comparative Medicine, College of Veterinary Medicine, University of Tennessee, Knoxville 37901-1071, USA.
authors.forename: E C
authors.initials: EC
authors.lastname: Ramsay
authors.forename: M R
authors.initials: MR
authors.lastname: Loomis
authors.forename: K G
authors.initials: KG
authors.lastname: Mehren
authors.forename: W S
authors.initials: WS
authors.lastname: Boardman
authors.forename: J
authors.initials: J
authors.lastname: Jensen
authors.forename: D
authors.initials: D
authors.lastname: Geiser
mesh_terms: D000075:Acepromazine / Q000008:administration & dosage / Q000494:pharmacology; D000759:Adjuvants, Anesthesia / Q000008:administration & dosage / Q000494:pharmacology; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000494:pharmacology; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D000836:Animals, Zoo / Q000502:physiology*; D001188:Artiodactyla / Q000502:physiology*; D001285:Atropine / Q000008:administration & dosage / Q000494:pharmacology; D001831:Body Temperature / Q000187:drug effects; D004174:Diprenorphine / Q000008:administration & dosage / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D005048:Etorphine / Q000008:administration & dosage / Q000494:pharmacology; D005215:Fasting / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D007103:Immobilization; D007273:Injections, Intramuscular / Q000662:veterinary; D007530:Isoflurane / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D009292:Narcotic Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D010092:Oximetry / Q000662:veterinary; D010100:Oxygen / Q000097:blood; D012119:Respiration / Q000187:drug effects; D012189:Retrospective Studies; D014991:Xylazine / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D000759:Adjuvants, Anesthesia; D000701:Analgesics, Opioid; D018685:Anesthetics, Inhalation; D018492:Dopamine Antagonists; D009292:Narcotic Antagonists; D004174:Diprenorphine; D014991:Xylazine; D005048:Etorphine; D000075:Acepromazine; D001285:Atropine; D007530:Isoflurane; D010100:Oxygen