{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T08:47:21Z","timestamp":1791794841970,"version":"4.3.4"},"reference-count":37,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T00:00:00Z","timestamp":1790899200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T00:00:00Z","timestamp":1790899200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"USDA Hatch Fund"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The objective of this experiment was to compare the clinical efficacy of various dosages of phenylbutazone (PBZ) with a negative control. The hypothesis was that higher PBZ doses would result in improved efficacy in a dose-dependent manner. Eight horses were shod with adjustable heart bar shoes on one front foot. Grade 4.0\/5.0 lameness was induced every 2 to 4 weeks by tightening a set screw against the heart bar. Heart rate (HR) and lameness score (LS) were monitored at rest; every 20 min after lameness induction for 5 h; and hourly for another 8 h. One hour after lameness induction, treatment was administered IV in a randomized blinded manner and included negative control (isotonic saline: SAL) or PBZ at 2.2 (LOW), 4.4 (MOD), or 8.8 (HIGH) mg\/kg body weight. Jugular blood samples were obtained at experiment hours 0, 1:05, 3, 5, 9, and 13, and were evaluated for plasma PBZ concentration. Results were compared using repeated measures analysis of variance and Student\u2013Newman\u2013Keul\u2019s test with the level of significance set at p &lt; 0.05. MOD and HIGH dose PBZ reduced HR from 3.0 h through 12.0 h and LS from 1.67 h through 12.0 h post-administration (p &lt; 0.05); there was no difference in response between MOD and HIGH dose PBZ. Compared to SAL, LOW dose PBZ reduced HR from 3.67 h through 5.0 h and LS from 3.67 h through 4.0 h after administration (p &lt; 0.05). The conclusions were that LOW dose PBZ was clinically effective for only a brief period compared to SAL, and HIGH dose was not more effective than MOD dose PBZ.<\/jats:p>","DOI":"10.3390\/ani16193096","type":"journal-article","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T08:15:18Z","timestamp":1790928918000},"page":"3096","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical Efficacy of Varying Dosages of Intravenous Phenylbutazone in a Reversible Model of Equine Foot Lameness"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9305-6120","authenticated-orcid":false,"given":"Jonathan H.","family":"Foreman","sequence":"first","affiliation":[{"name":"Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, IL 61802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,2]]},"reference":[{"key":"ref_1","unstructured":"Tobin, T. 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