{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T10:51:37Z","timestamp":1767955897435,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T00:00:00Z","timestamp":1767916800000},"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>Sheep are routinely used as orthopedic models due to their similarities to human joints. Spinal anesthesia provides adequate analgesia for these procedures, and its duration can be enhanced with adjuvant drugs. Clonidine is commonly used in human spinal anesthesia, while dexmedetomidine is a newer and more selective \u03b1-2 agonist. This study compared the duration and analgesic effect of these two drugs as adjuvants in spinal anesthesia. Thirty-nine sheep undergoing experimental pelvic limb cartilage damage surgery were enrolled. Animals were sedated with diazepam (0.4 mg kg\u22121) and buprenorphine (10 \u03bcg kg\u22121) intravenously. Propofol was given as needed (0.5 mg kg\u22121) and oxygen support via face mask was continuous. Animals were positioned with the treated limb in a dependent position for the lumbosacral spinal block. Sheep were divided into three groups (n = 13), receiving lidocaine 2% (L group), lidocaine 2% + clonidine 20 \u03bcg mL\u22121 (CL group), or lidocaine 2% + dexmedetomidine 1 \u03bcg mL\u22121 (LD group) for spinal block (1 mL every 10 kg). Recovery times (minute) from the spinal block were recorded: anal sphincter tone (AS), recovery of sensibility (RoS), first limb movements (FMov), time of standing (ToS), and first rescue analgesia; ataxia (ATA) was also measured after standing. Dexmedetomidine increased the duration of spinal anesthesia, affecting both motor and sensory functions.<\/jats:p>","DOI":"10.3390\/ani16020197","type":"journal-article","created":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T09:25:02Z","timestamp":1767950702000},"page":"197","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dexmedetomidine Versus Clonidine as an Adjuvant to Lidocaine Spinal Anesthesia in an Ovine Experimental Model"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-1397-6109","authenticated-orcid":false,"given":"Claudia","family":"Piemontese","sequence":"first","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-5803-2070","authenticated-orcid":false,"given":"Caterina","family":"Vicenti","sequence":"additional","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alberto Maria","family":"Crovace","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, Piazza Universit\u00e0, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-8890-9859","authenticated-orcid":false,"given":"Roberta","family":"Pizzi","sequence":"additional","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6252-3179","authenticated-orcid":false,"given":"Marzia","family":"Stabile","sequence":"additional","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4917-355X","authenticated-orcid":false,"given":"Marta","family":"Guadalupi","sequence":"additional","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4963-8673","authenticated-orcid":false,"given":"Luca","family":"Lacitignola","sequence":"additional","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2085-376X","authenticated-orcid":false,"given":"Francesco","family":"Staffieri","sequence":"additional","affiliation":[{"name":"Department of Precision and Regenerative Medicine and Jonic Area (DiMePRe-J), University of Bari, Piazza Umberto I, 70121 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,9]]},"reference":[{"key":"ref_1","first-page":"292","article-title":"Sheep model in orthopedic research: A literature review","volume":"51","author":"Martini","year":"2001","journal-title":"Comp. 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