{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:52:08Z","timestamp":1760230328859,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,7,18]],"date-time":"2022-07-18T00:00:00Z","timestamp":1658102400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n Proyectos Torres Quevedo","doi-asserted-by":"publisher","award":["PTQ-09-02-01982"],"award-info":[{"award-number":["PTQ-09-02-01982"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Hormonal treatments used in the artificial insemination (AI) of sheep can cause several physiological problems that can affect negatively fertility and animal health; however, AI protocols based on the detection of natural estrus offer a more sustainable option and can achieve high fertility. In this study, an AI protocol at natural estrus in organic Churra sheep was performed. In the first phase (AI protocol development), 125 ewes were exocervically inseminated, and their fertility was assessed based on the following factors: number of AI, physiological state, body condition, estrus detection\u2013AI interval, and vaginal fluids in cervix. That protocol was repeated for six consecutive years. In all individuals, fertilities based on the timing of insemination after estrus detection were very high. Lactating ewes produced better results than did dry ewes, which was probably because of the better feeding of the former. In addition, double insemination increased the fertility of ewes whose estrus was detected within 16 h of onset. Body condition and amount of vaginal fluid were correlated with fertility. Exocervical inseminations at natural estrus can produce acceptable fertility and prolificity in Churra ewes.<\/jats:p>","DOI":"10.3390\/vetsci9070370","type":"journal-article","created":{"date-parts":[[2022,7,19]],"date-time":"2022-07-19T00:19:21Z","timestamp":1658189961000},"page":"370","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Efficiency of Artificial Insemination at Natural Estrus in Organic Churra Ewes"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5876-6226","authenticated-orcid":false,"given":"Carlos","family":"Palacios","sequence":"first","affiliation":[{"name":"Faculty of Environmental and Agricultural Sciences, University of Salamanca, Avenida Filiberto Villalobos 119-129, 37007 Salamanca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2827-3054","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Abecia","sequence":"additional","affiliation":[{"name":"Institute of Research in Environmental Sciences of Arag\u00f3n (IUCA), University of Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8908-1606","authenticated-orcid":false,"given":"Javier","family":"Plaza","sequence":"additional","affiliation":[{"name":"Faculty of Environmental and Agricultural Sciences, University of Salamanca, Avenida Filiberto Villalobos 119-129, 37007 Salamanca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristina","family":"Hidalgo","sequence":"additional","affiliation":[{"name":"Faculty of Economic and Business Science, University of Le\u00f3n, Campus de Vegazana s\/n, 24071 Le\u00f3n, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0882-5552","authenticated-orcid":false,"given":"Luis F.","family":"de la Fuente","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, University of Le\u00f3n, Campus de Vegazana s\/n, 24071 Le\u00f3n, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"195","DOI":"10.22256\/pubvet.v9n5.220-231","article-title":"T\u00e9cnicas de insemina\u00e7\u00e3o artificial e implica\u00e7\u00f5es fisiopatol\u00f3gicas em ovinos [Artificial insemination techniques and pathophysiological implications in sheep]","volume":"9","author":"Alvares","year":"2015","journal-title":"PUBVET"},{"key":"ref_2","first-page":"49","article-title":"Inducci\u00f3n y Sincronizaci\u00f3n de Celo y La Ovulaci\u00f3n En La Oveja; Utilizaci\u00f3n En La Inseminaci\u00f3n Artificial [Induction and Synchronization of Oestrus and Ovulation in the Ewe; Use in Artificial Insemination]","volume":"36","year":"1995","journal-title":"Ovis"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1016\/j.smallrumres.2019.03.018","article-title":"Organic Breeding in Sarda Ewes: Utilization of the Ram Effect in an Artificial Insemination Program","volume":"174","author":"Mayorga","year":"2019","journal-title":"Small Rumin. 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