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Different gonadotropin\u2010releasing hormone (GnRH) agonists have been developed to gain better control of follicular development, timing, and ovulation quality; therefore, they have been extensively used in FTAI protocols. This literature review resumes the most important characteristics of the physiology of follicular development and ovulation in sows, followed by a discussion about the hormonal alternatives available to induce ovulation (human chorionic gonadotropin, hCG; porcine luteinizing hormone, LH and GnRH agonists). Also, ovulation induction failures with GnRH agonists are described. Finally, current FTAI protocols with GnRH agonists are resumed and discussed. FTAI with GnRH agonists has proven to be an efficient, successful reproductive protocol that can be implemented in pig farms due to better knowledge of an endocrine system that regulates follicular development and ovulation and increased availability of several GnRH agonists that allow more efficient reproductive swine programs.<\/jats:p>","DOI":"10.1111\/rda.14326","type":"journal-article","created":{"date-parts":[[2023,2,7]],"date-time":"2023-02-07T07:03:10Z","timestamp":1675753390000},"page":"571-582","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["GnRH agonists: Updating fixed\u2010time artificial insemination protocols in sows"],"prefix":"10.1111","volume":"58","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6964-7011","authenticated-orcid":false,"given":"Mar\u00eda Victoria","family":"Falceto","sequence":"first","affiliation":[{"name":"Agroalimentary Institute of Aragon\u2010IA2, Department of Animal Pathology Universidad de Zaragoza\u2010CITA Zaragoza Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9s","family":"Su\u00e1rez\u2010Usbeck","sequence":"additional","affiliation":[{"name":"Department of Animal Pathology Universidad de Zaragoza Zaragoza Spain"},{"name":"Facultad de Ciencias Pecuarias Escuela Superior Polit\u00e9cnica de Chimborazo Riobamba Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5026-5144","authenticated-orcid":false,"given":"Mar\u00eda Teresa","family":"Tejedor","sequence":"additional","affiliation":[{"name":"Department of Anatomy, Embriology and Animal Genetics, CiberCV Universidad de Zaragoza Zaragoza Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raquel","family":"Ausejo","sequence":"additional","affiliation":[{"name":"Department of Animal Pathology Universidad de Zaragoza Zaragoza Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana Mar\u00eda","family":"Garrido","sequence":"additional","affiliation":[{"name":"Department of Animal Pathology Universidad de Zaragoza Zaragoza Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9907-2941","authenticated-orcid":false,"given":"Olga","family":"Mitjana","sequence":"additional","affiliation":[{"name":"Agroalimentary Institute of Aragon\u2010IA2, Department of Animal Pathology Universidad de Zaragoza\u2010CITA Zaragoza Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2023,2,20]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0093-691X(00)00281-8"},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1439-0531.2004.00500.x"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1111\/rda.12805"},{"key":"e_1_2_10_5_1","doi-asserted-by":"publisher","DOI":"10.1590\/S1413-95962001000300009"},{"key":"e_1_2_10_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.mce.2013.10.015"},{"issue":"4","key":"e_1_2_10_7_1","doi-asserted-by":"crossref","first-page":"182","DOI":"10.54846\/jshap\/536","article-title":"Equine chorionic gonadotrophin and porcine luteinizing hormone to shorten and synchronize the wean\u2010to\u2010breed interval among parity\u2010one and parity\u2010two sows","volume":"16","author":"Bennett\u2010Steward K.","year":"2008","journal-title":"Journal of Swine Health and Production"},{"key":"e_1_2_10_8_1","first-page":"37","article-title":"Control of follicular development during and after lactation in sows","volume":"33","author":"Britt J. 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