{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T21:31:59Z","timestamp":1779312719885,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,5,31]],"date-time":"2023-05-31T00:00:00Z","timestamp":1685491200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hong Kong Jockey Club"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The impact of recommended withholding periods (RWPs) for omeprazole on the recurrence of Equine Gastric Ulcer Syndrome (EGUS) is unknown. The study was designed to compare the effect of two RWPs on EGUS recurrence post-omeprazole treatment and to determine if a nutraceutical supplement would reduce EGUS recurrence when administrated during an RWP. The study was a blinded, randomized clinical trial. Part 1: Horses were allocated to an RWP0 or RWP2 and crossed over after 4-weeks. Horses received oral omeprazole once daily, except during the RWPs at the end of the treatment periods. Part 2: Horses received omeprazole for 21 days prior to an RWP2 during which they received a nutraceutical supplement. Gastroscopy was performed on Day 0 and pre- and post- RWP. Part 1: More horses were affected by Equine Squamous Gastric Disease (ESGD) after the \u20182-clear-days\u2019 RWP than the \u2018not on race-day\u2019 RWP (p = 0.012). The prevalence of ESGD post-RWP for \u20182-clear-days\u2019 did not differ from day 0 (p = 0.478). Part 2: The prevalence of ESGD post-RWP was lower than on Day 0 (p = 0.046). A difference in recurrence of ESGD was present between the two common RWPs. The implications of this on the welfare of Thoroughbred racehorses warrant further discussion.<\/jats:p>","DOI":"10.3390\/ani13111823","type":"journal-article","created":{"date-parts":[[2023,6,1]],"date-time":"2023-06-01T01:40:56Z","timestamp":1685583656000},"page":"1823","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["The Impact of Two Recommended Withholding Periods for Omeprazole and the Use of a Nutraceutical Supplement on Recurrence of Equine Gastric Ulcer Syndrome in Thoroughbred Racehorses"],"prefix":"10.3390","volume":"13","author":[{"given":"Ran","family":"Shan","sequence":"first","affiliation":[{"name":"Department of Veterinary Clinical Services, The Hong Kong Jockey Club, Conghua Racecourse, Guangzhou 510900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7106-7884","authenticated-orcid":false,"given":"Catherine M.","family":"Steel","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical Services, The Hong Kong Jockey Club, Conghua Racecourse, Guangzhou 510900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ben","family":"Sykes","sequence":"additional","affiliation":[{"name":"School of Veterinary Sciences, Massey University, Private Bag, 11-222, Palmerston North 4442, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1288","DOI":"10.1111\/jvim.13578","article-title":"European College of Equine Internal Medicine\u2014Consensus Statement Equine Gastric Ulcer Syndrome (EGUS) in Adult Horses","volume":"29","author":"Sykes","year":"2015","journal-title":"J. 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