{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T22:13:41Z","timestamp":1784758421604,"version":"3.55.0"},"reference-count":46,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,3,3]],"date-time":"2025-03-03T00:00:00Z","timestamp":1740960000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Centro para el Desarrollo Tecnol\u00f3gico Industrial\u2019 (Spanish Ministry for Science and Innovation)","award":["IDI-20200342"],"award-info":[{"award-number":["IDI-20200342"]}]},{"name":"Centro para el Desarrollo Tecnol\u00f3gico Industrial\u2019 (Spanish Ministry for Science and Innovation)","award":["Group A25_23R"],"award-info":[{"award-number":["Group A25_23R"]}]},{"name":"Government of Aragon, Grant Research Group Funds","award":["IDI-20200342"],"award-info":[{"award-number":["IDI-20200342"]}]},{"name":"Government of Aragon, Grant Research Group Funds","award":["Group A25_23R"],"award-info":[{"award-number":["Group A25_23R"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>This study assessed the effects of using a total mixed ration (TMR), compared to distributing the concentrate and the forage separately, on the productive performance of beef cattle fed high-concentrate diets and on rumen fermentation characteristics, including methane production. Eighteen rumen-fistulated beef calves were fed a concentrate plus pelleted barley straw separately (CS; n = 9) or as TMR (n = 9). Average daily gain and intake of TMR and of straw and concentrate with the CS treatment were recorded. Digestibility was estimated using ashes insoluble in hydrochloric acid as a marker. Rumen liquid and gas samples were obtained, and the abundance of total bacteria, methanogens, protozoa, and anaerobic fungi was analysed. Animals were slaughtered at 500 kg live weight (LW), and dressing percentage and carcass classification were obtained. Another 49 animals for each treatment were used on a commercial farm to exclusively assess animal performance. The treatment (CS or TMR) did not significantly affect (p &gt; 0.05) final LW, average daily gain, carcass dressing percentage, dry matter or digestible organic matter intake, digestibility values, production of methane and carbon dioxide, and abundance of microorganisms in the rumen. However, animals fed TMR had lower rumen pH (5.87 vs. 5.58, p = 0.041 for CS and TMR), suggesting a higher risk of experiencing rumen acidosis than those fed straw and concentrate separately. In conclusion, using a total mixed ration does not seem a suitable strategy to reduce methane production or prevent rumen acidosis in feedlot cattle.<\/jats:p>","DOI":"10.3390\/ani15050723","type":"journal-article","created":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T04:58:17Z","timestamp":1741064297000},"page":"723","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Unmixed Diet Versus Total Mixed Ration in Beef Cattle Fed High-Concentrate Diets: Effects on Methane Emissions, Animal Performance, and Rumen Fermentation"],"prefix":"10.3390","volume":"15","author":[{"given":"Amira","family":"Arbaoui","sequence":"first","affiliation":[{"name":"Departamento de Producci\u00f3n Animal y Ciencia de los Alimentos, Instituto Agroalimentario de Arag\u00f3n (IA2), Universidad de Zaragoza-CITA, Miguel Servet 177, 50013 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-6478-7857","authenticated-orcid":false,"given":"Gonzalo","family":"Gonzalo","sequence":"additional","affiliation":[{"name":"Servicio de Experimentaci\u00f3n Animal, Universidad de Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5880-6021","authenticated-orcid":false,"given":"Alejandro","family":"Belanche","sequence":"additional","affiliation":[{"name":"Departamento de Producci\u00f3n Animal y Ciencia de los Alimentos, Instituto Agroalimentario de Arag\u00f3n (IA2), Universidad de Zaragoza-CITA, Miguel Servet 177, 50013 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8753-8887","authenticated-orcid":false,"given":"Antonio","family":"de Vega","sequence":"additional","affiliation":[{"name":"Departamento de Producci\u00f3n Animal y Ciencia de los Alimentos, Instituto Agroalimentario de Arag\u00f3n (IA2), Universidad de Zaragoza-CITA, Miguel Servet 177, 50013 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.anifeedsci.2010.07.002","article-title":"Influence of hydrogen on rumen methane formation and fermentation balances through microbial growth kinetics and fermentation thermodynamics","volume":"160","author":"Janssen","year":"2010","journal-title":"Anim. 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