{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T23:46:45Z","timestamp":1784764005316,"version":"3.55.0"},"reference-count":31,"publisher":"American Veterinary Medical Association (AVMA)","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2006,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n<jats:p><jats:bold>Objective<\/jats:bold>\u2014To compare serum concentrations of liposome-encapsulated butorphanol tartrate (LEBT) and standard butorphanol tartrate (STDBT) following SC and IM administration, respectively, and to evaluate analgesic effects of LEBT and STDBT after parenteral administration to Hispaniolan parrots.<\/jats:p>\n<jats:p><jats:bold>Animals<\/jats:bold>\u201411 adult Hispaniolan parrots.<\/jats:p>\n<jats:p><jats:bold>Procedure<\/jats:bold>\u2014The ability of LEBT to prolong the duration of analgesia in an avian species was tested. Blood samples were collected at serial time points after SC administration of LEBT (10 mg\/kg or 15 mg\/kg) or IM administration of STDBT (5 mg\/kg). Serum concentrations of butorphanol tartrate were determined by use of a commercial immunoassay that measured parent drug and metabolites. Analgesic efficacy was evaluated in parrots exposed to electrical and thermal stimuli. Foot withdrawal thresholds were recorded at baseline and at serial time points after LEBT (15 mg\/kg), liposome vehicle, STDBT (2 mg\/kg), or physiologic saline (0.9% NaCl) solution administration.<\/jats:p>\n<jats:p><jats:bold>Results<\/jats:bold>\u2014LEBT had a prolonged in vivo release for up to 5 days. Negligible serum butorphanol and butorphanol metabolite concentrations were obtained at 24 hours after IM administration of STDBT. Analgesic efficacy of LEBT as measured by foot withdrawal threshold to noxious thermal and electrical stimuli persisted for 3 to 5 days following SC administration of LEBT.<\/jats:p>\n<jats:p><jats:bold>Conclusions and Clinical Relevance<\/jats:bold>\u2014SC administration of LEBT provided analgesia and detectable serum butorphanol concentrations in Hispaniolan parrots for up to 5 days. The use of LEBT may allow for substantial improvement in long-term pain relief without subjecting birds to the stress of handling and multiple daily injections.<\/jats:p>","DOI":"10.2460\/ajvr.67.5.775","type":"journal-article","created":{"date-parts":[[2006,5,1]],"date-time":"2006-05-01T16:31:51Z","timestamp":1146501111000},"page":"775-781","source":"Crossref","is-referenced-by-count":80,"title":["Serum concentrations and analgesic effects of liposome-encapsulated and standard butorphanol tartrate in parrots"],"prefix":"10.2460","volume":"67","author":[{"given":"Kurt K.","family":"Sladky","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lisa","family":"Krugner-Higby","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth","family":"Meek-Walker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Timothy 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post-surgical analgesia in ferrets (Mustela putorius furo)","volume":"39","author":"Sladky","year":"2000"},{"key":"ref5","series-title":"J Am Vet Med Assoc","doi-asserted-by":"publisher","first-page":"692","DOI":"10.2460\/javma.2004.224.692","article-title":"Study of pain and analgesia: a call for a cross-species approach","volume":"224","author":"Paul-Murphy","year":"2004"},{"key":"ref6","series-title":"Annu Conf Assoc Avian Vet","first-page":"17","article-title":"Evaluation of the isoflurane-sparing effects of butorphanol and flunixin in psittaciformes, in Proceedings","author":"Curro","year":"1993"},{"key":"ref7","series-title":"Vet Surg","doi-asserted-by":"publisher","first-page":"429","DOI":"10.1111\/j.1532-950X.1994.tb00502.x","article-title":"Determination of the ED50 of isoflurane and evaluation of the analgesic properties of butorphanol in cockatoos (Cacatua spp.)","volume":"23","author":"Curro","year":"1994"},{"key":"ref8","series-title":"Res Vet Sci","doi-asserted-by":"publisher","first-page":"263","DOI":"10.1016\/S0034-5288(97)90031-X","article-title":"Evaluation of a protocol for determining the effectiveness of pretreatment with local analgesics for reducing experimentally induced articular pain in domestic fowl","volume":"63","author":"Hocking","year":"1997"},{"key":"ref9","series-title":"J Avian Med Surg","first-page":"276","article-title":"Round table discussion: pain management in clinical practice","volume":"12","author":"Clubb","year":"1998"},{"key":"ref10","series-title":"Vet Rec","doi-asserted-by":"publisher","first-page":"668","DOI":"10.1136\/vr.144.24.668","article-title":"Effect of carprofen on lameness in broiler chickens","volume":"144","author":"McGeown","year":"1999"},{"key":"ref11","series-title":"Am J Vet Res","first-page":"1218","article-title":"Analgesic effects of butorphanol and buprenorphine in conscious African grey parrots (Psittacus erithacus erithacus and Psittacus erithacus timneh)","volume":"60","author":"Paul-Murphy","year":"1999"},{"key":"ref12","series-title":"Pharmacol Biochem Behav","doi-asserted-by":"publisher","first-page":"339","DOI":"10.1016\/S0091-3057(99)00029-5","article-title":"Evaluation of intraarticular opioid analgesia for the relief of articular pain in the domestic fowl","volume":"63","author":"Gentle","year":"1999"},{"key":"ref13","series-title":"The veterinary clinics of North America: exotic animal practice","first-page":"35","article-title":"Avian analgesia","author":"Paul-Murphy","year":"2000"},{"key":"ref14","series-title":"Vet Rec","doi-asserted-by":"publisher","first-page":"307","DOI":"10.1136\/vr.146.11.307","article-title":"Self-selection of the analgesic drug carprofen by lame broiler chickens","volume":"146","author":"Danbury","year":"2000"},{"key":"ref15","series-title":"Recent advances in veterinary anesthesia and analgesia: companion animals","article-title":"Injectable anesthesia and analgesia of birds","author":"Paul-Murphy","year":"2001"},{"key":"ref16","series-title":"J Avian Med Surg","doi-asserted-by":"publisher","first-page":"124","DOI":"10.1647\/2002-008","article-title":"Disposition and analgesic effects of fentanyl in the umbrella cockatoo (Cacatua alba)","volume":"17","author":"Hoppes","year":"2003"},{"key":"ref17","series-title":"J Avian Med Surg","doi-asserted-by":"publisher","first-page":"224","DOI":"10.1647\/2001-039","article-title":"Pharmacokinetic properties of a single intramuscular dose of buprenorphine in African grey parrots (Psittacus erithacus erithacus)","volume":"18","author":"Paul-Murphy","year":"2004"},{"key":"ref18","series-title":"J Gen Intern Med","doi-asserted-by":"publisher","first-page":"688","DOI":"10.1007\/BF02598290","article-title":"Abuse potential of various opioid medications","volume":"8","author":"Brookoff","year":"1993"},{"key":"ref19","series-title":"Cancer Chemother Pharmacol","doi-asserted-by":"publisher","first-page":"187","DOI":"10.1007\/BF00686214","article-title":"Extended-release formulation of morphine for subcutaneous administration","volume":"33","author":"Kim","year":"1993"},{"key":"ref20","series-title":"Anesthesiology","doi-asserted-by":"publisher","first-page":"331","DOI":"10.1097\/00000542-199608000-00015","article-title":"Sustained-release morphine for epidural analgesia in rats","volume":"85","author":"Kim","year":"1996"},{"key":"ref21","series-title":"Anesthesiology","first-page":"402","article-title":"Serum concentrations and efficacy of epidurally delivered sustained-release encapsulated morphine in dogs","volume":"90","author":"Yaksh","year":"1999"},{"key":"ref22","series-title":"Contemp Top Lab Anim Sci","first-page":"21","article-title":"A comparison of two opioid analgesics for relief of visceral pain induced by intestinal resection in rats","volume":"40","author":"Clark","year":"2001"},{"key":"ref23","series-title":"Comp Med","first-page":"270","article-title":"Liposome-encapsulated oxymorphone hydrochloride provides prolonged relief of postsurgical visceral pain in rats","volume":"53","author":"Krugner-Higby","year":"2002"},{"key":"ref24","series-title":"Comp Med","first-page":"280","article-title":"A single dose of liposome-encapsulated oxymorphone or morphine provides long-term analgesia in an animal model of neuropathic pain","volume":"53","author":"Smith","year":"2003"},{"key":"ref25","series-title":"J Vet Pharmacol Ther","doi-asserted-by":"publisher","first-page":"369","DOI":"10.1111\/j.1365-2885.2004.00582.x","article-title":"Sedative effects and serum drug concentrations of oxymorphone and metabolites after subcutaneous administration of a liposome-encapsulated formulation in dogs","volume":"27","author":"Smith","year":"2004"},{"key":"ref26","series-title":"Comp Med","first-page":"558","article-title":"Evaluation of liposome-encapsulated oxymorphone hydrochloride in mice after splenectomy","volume":"54","author":"Clark","year":"2004"},{"key":"ref27","series-title":"Am J Vet Res","first-page":"1213","article-title":"A technique for evaluating analgesia in conscious perching birds","volume":"60","author":"Paul-Murphy","year":"1999"},{"key":"ref28","series-title":"Animal pain","first-page":"453","article-title":"Animal models for the evaluation of analgesic agents","author":"Raffe","year":"1992"},{"key":"ref29","series-title":"Liposome technology","first-page":"19","article-title":"A simple procedure for preparing liposomes capable of high encapsulation efficiency under mild conditions","author":"Kirby","year":"1984"},{"key":"ref30","series-title":"Methods Enzymol","doi-asserted-by":"publisher","first-page":"111","DOI":"10.1016\/0076-6879(87)49048-4","article-title":"Covalent attachment of proteins to liposomes","volume":"149","author":"Heath","year":"1987"},{"key":"ref31","series-title":"SAS Statview reference guide: version 5.0.1 (for MacIntosh and Windows)","first-page":"120","year":"1998"}],"container-title":["American Journal of Veterinary 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