{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T17:04:16Z","timestamp":1776877456310,"version":"3.51.2"},"reference-count":42,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,5,19]],"date-time":"2020-05-19T00:00:00Z","timestamp":1589846400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["AGL2017-84681-R"],"award-info":[{"award-number":["AGL2017-84681-R"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["RYC-2017-21545"],"award-info":[{"award-number":["RYC-2017-21545"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["RTI2018-093548-B-I00"],"award-info":[{"award-number":["RTI2018-093548-B-I00"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100014181","name":"Junta de Extremadura","doi-asserted-by":"publisher","award":["TA18008"],"award-info":[{"award-number":["TA18008"]}],"id":[{"id":"10.13039\/501100014181","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015720","name":"Universidad de Extremadura","doi-asserted-by":"publisher","award":["Acci\u00f3n II Beca RC4"],"award-info":[{"award-number":["Acci\u00f3n II Beca RC4"]}],"id":[{"id":"10.13039\/501100015720","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Production of equine embryos in vitro is currently a commercial technique and a reliable way of obtaining offspring. In order to produce those embryos, immature oocytes are retrieved from postmortem ovaries or live mares by ovum pick-up (OPU), matured in vitro (IVM), fertilized by intracytoplasmic sperm injection (ICSI), and cultured until day 8\u201310 of development. However, at best, roughly 10% of the oocytes matured in vitro and followed by ICSI end up in successful pregnancy and foaling, and this could be due to suboptimal IVM conditions. Hence, in the present work, we aimed to elucidate the major metabolites present in equine preovulatory follicular fluid (FF) obtained from postmortem mares using proton nuclear magnetic resonance spectroscopy (1H-NMR). The results were contrasted against the composition of the most commonly used media for equine oocyte IVM: tissue culture medium 199 (TCM-199) and Dulbecco\u2019s modified eagle medium\/nutrient mixture F-12 Ham (DMEM\/F-12). Twenty-two metabolites were identified in equine FF; among these, nine of them are not included in the composition of DMEM\/F-12 or TCM-199 media, including (mean \u00b1 SEM): acetylcarnitine (0.37 \u00b1 0.2 mM), carnitine (0.09 \u00b1 0.01 mM), citrate (0.4 \u00b1 0.04 mM), creatine (0.36 \u00b1 0.14 mM), creatine phosphate (0.36 \u00b1 0.05 mM), fumarate (0.05 \u00b1 0.007 mM), glucose-1-phosphate (6.9 \u00b1 0.4 mM), histamine (0.25 \u00b1 0.01 mM), or lactate (27.3 \u00b1 2.2 mM). Besides, the mean concentration of core metabolites such as glucose varied (4.3 mM in FF vs. 5.55 mM in TCM-199 vs. 17.5 mM in DMEM\/F-12). Hence, our data suggest that the currently used media for equine oocyte IVM can be further improved.<\/jats:p>","DOI":"10.3390\/ani10050883","type":"journal-article","created":{"date-parts":[[2020,5,20]],"date-time":"2020-05-20T02:48:24Z","timestamp":1589942904000},"page":"883","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Study of the Metabolomics of Equine Preovulatory Follicular Fluid: A Way to Improve Current In Vitro Maturation Media"],"prefix":"10.3390","volume":"10","author":[{"given":"Pablo","family":"Fern\u00e1ndez-Hern\u00e1ndez","sequence":"first","affiliation":[{"name":"Research Group of Intracellular Signaling and Technology of Reproduction, Research Institute INBIO G + C, University of Extremadura, 10003 C\u00e1ceres, Spain"},{"name":"Department of Animal Medicine, Faculty of Veterinary Sciences, University of Extremadura, 10003 C\u00e1ceres, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0801-2327","authenticated-orcid":false,"given":"Mar\u00eda Jes\u00fas","family":"S\u00e1nchez-Calabuig","sequence":"additional","affiliation":[{"name":"Department of Animal Reproduction, INIA, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, University Complutense of Madrid, 28040 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1795-7381","authenticated-orcid":false,"given":"Luis Jes\u00fas","family":"Garc\u00eda-Mar\u00edn","sequence":"additional","affiliation":[{"name":"Research Group of Intracellular Signaling and Technology of Reproduction, Research Institute INBIO G + C, University of Extremadura, 10003 C\u00e1ceres, Spain"},{"name":"Department of Physiology, Faculty of Veterinary Sciences, University of Extremadura, 10003 C\u00e1ceres, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7770-0775","authenticated-orcid":false,"given":"Mar\u00eda J.","family":"Bragado","sequence":"additional","affiliation":[{"name":"Research Group of Intracellular Signaling and Technology of Reproduction, Research Institute INBIO G + C, University of Extremadura, 10003 C\u00e1ceres, Spain"},{"name":"Department of Biochemistry and Molecular Biology and Genetics, Faculty of Veterinary Sciences, University of Extremadura, 10003 C\u00e1ceres, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9893-9179","authenticated-orcid":false,"given":"Alfonso","family":"Guti\u00e9rrez-Ad\u00e1n","sequence":"additional","affiliation":[{"name":"Department of Animal Reproduction, INIA, 28040 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8748-4105","authenticated-orcid":false,"given":"\u00d3scar","family":"Millet","sequence":"additional","affiliation":[{"name":"Precision Medicine and Metabolism Lab., CICbioGUNE, 48160 Vizcaya, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4252-8180","authenticated-orcid":false,"given":"Chiara","family":"Bruzzone","sequence":"additional","affiliation":[{"name":"Precision Medicine and Metabolism Lab., CICbioGUNE, 48160 Vizcaya, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5568-548X","authenticated-orcid":false,"given":"Lauro","family":"Gonz\u00e1lez-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Research Group of Intracellular Signaling and Technology of Reproduction, Research Institute INBIO G + C, University of Extremadura, 10003 C\u00e1ceres, Spain"},{"name":"Department of Biochemistry and Molecular Biology and Genetics, Faculty of Veterinary Sciences, University of Extremadura, 10003 C\u00e1ceres, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5331-9793","authenticated-orcid":false,"given":"Beatriz","family":"Mac\u00edas-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Research Group of Intracellular Signaling and Technology of Reproduction, Research Institute INBIO G + C, University of Extremadura, 10003 C\u00e1ceres, Spain"},{"name":"Department of Animal Medicine, Faculty of Veterinary Sciences, University of Extremadura, 10003 C\u00e1ceres, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1111\/rda.13259","article-title":"Assisted reproductive techniques in mares","volume":"53","author":"Hinrichs","year":"2018","journal-title":"Reprod. 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