{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T11:28:57Z","timestamp":1773055737084,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T00:00:00Z","timestamp":1630368000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>While butorphanol is the most commonly used opioid in horses, methadone is not licensed in most countries. Our aim was to compare the effects of both drugs, combined with romifidine, regarding the quality of sedation and induction in horses undergoing elective surgery. Results indicate the suitability of both methadone and butorphanol in this patient population. Animals were scored 10 min after intravenous injection of sedatives. Despite lower overall sedation (OS) score in horses receiving methadone (p = 0.002), the quality and time of induction and intubation remained unchanged. None of the horses had the lowest OS score (no sedation), nor the highest score for ataxia (horse falling). Methadone induced a tendency for minor noise reaction yet minor head lowering scores, the latter being probably the most influencing parameter when scoring OS. Measured physiological parameters decreased in both groups, with greater bradycardia recorded after methadone (p = 0.017), including a higher incidence of atrioventricular blocks that resolved during general anaesthesia. The quality of induction was good\u2013excellent in most of the animals. While comparisons between the degree of antinociception were beyond the scope of this study, analgesic potency might influence the choice when considering opioids as pre-anaesthetic drugs in combination with romifidine before surgery in equines.<\/jats:p>","DOI":"10.3390\/ani11092572","type":"journal-article","created":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T21:59:45Z","timestamp":1630447185000},"page":"2572","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Methadone or Butorphanol as Pre-Anaesthetic Agents Combined with Romifidine in Horses Undergoing Elective Surgery: Qualitative Assessment of Sedation and Induction"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7774-9920","authenticated-orcid":false,"given":"Sara","family":"Nannarone","sequence":"first","affiliation":[{"name":"Department of Veterinary Medicine, Perugia University, Via San Costanzo 4, 06126 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0490-7721","authenticated-orcid":false,"given":"Giacomo","family":"Giannettoni","sequence":"additional","affiliation":[{"name":"ADVETIA Centre Hospitalier V\u00e9t\u00e9rinaire, V\u00e9lizy-Villacoublay, \u00cele-de-France, 78140 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chiara","family":"Laurenza","sequence":"additional","affiliation":[{"name":"Section of Anesth\u00e9siologie, Universit\u00e9 de Lyon, VetAgro Sup, Marcy l\u2019Etoile, 69280 Lyon, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3615-0978","authenticated-orcid":false,"given":"Andrea","family":"Giontella","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, Perugia University, Via San Costanzo 4, 06126 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8765-8750","authenticated-orcid":false,"given":"Giulia","family":"Moretti","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, Perugia University, Via San Costanzo 4, 06126 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/j.neuint.2007.06.036","article-title":"Alpha2-adrenoceptor subtypes\u2014Unex-pected functions for receptors and ligands derived from gene-targeted mouse models","volume":"51","author":"Knaus","year":"2007","journal-title":"Neurochem. 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