{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:30:53Z","timestamp":1787027453142,"version":"build-2736575974"},"reference-count":47,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,24]],"date-time":"2022-12-24T00:00:00Z","timestamp":1671840000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Natural Sciences and Engineering Research Council of Canada"},{"name":"Buckeye Feed Mills, Dalton, OH, USA"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Oral electrolyte supplementation may influence acid-base state during exercise due to the intestinal absorption of administered water and electrolytes used to mitigating sweat losses. This study examined the effect of pre-exercise electrolyte supplementation (3 and 8 L) on plasma acid-base variables at rest, during moderate intensity exercise and during recovery. It was hypothesized that electrolyte supplementation will result in improved acid-base state compared to the alkalosis typical of prolonged exercise. In randomized crossover fashion, four horses were administered 3 L or 8 L of a hypotonic electrolyte solution (PNW) intended to replace sweat losses, or water alone (CON), 1 h before treadmill exercise to fatigue (at 35% of peak VO2) or for 45 min at 50% peak VO2. Blood was sampled at 10-min intervals before, during and after exercise, and analyzed for dependent and independent acid-base variables. Effects of 3 L of supplementation at low exercise intensities were minimal. In the 8 L trials, plasma [H+] decreased (p &lt; 0.05) during exercise and early recovery in CON but not PNW. Plasma TCO2 decreased (p &lt; 0.05) by 30 min after PNW reaching a nadir of 28.0 \u00b1 1.5 mmol\/L during the early exercise period (p = 0.018). Plasma pCO2 and strong ion difference [SID] were the primary contributors to changes in [H+] and [TCO2], respectively. Pre-exercise PNW of 8 L intended to fully replenish sweat loses maintained [H+], decreased [TCO2] and mitigated the mild alkalosis during moderate intensity exercise.<\/jats:p>","DOI":"10.3390\/ani13010073","type":"journal-article","created":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T07:30:06Z","timestamp":1672126206000},"page":"73","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Tracing Acid-Base Variables in Exercising Horses: Effects of Pre-Loading Oral Electrolytes"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1522-6021","authenticated-orcid":false,"given":"Amanda P.","family":"Waller","sequence":"first","affiliation":[{"name":"Center for Clinical & Translational Research, Nationwide Children\u2019s Hospital, Columbus, OH 43205, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1001-4302","authenticated-orcid":false,"given":"Michael I.","family":"Lindinger","sequence":"additional","affiliation":[{"name":"Research and Development, The Nutraceutical Alliance Inc., Guelph, ON N1E 2G7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1079\/ECP200549","article-title":"Physicochemical Analysis of Acid\u2013Base Status during Recovery from High-Intensity Exercise in Standardbred Racehorses","volume":"2","author":"Waller","year":"2005","journal-title":"Equine Comp. 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