{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T05:04:34Z","timestamp":1789362274749,"version":"build-2803163510"},"reference-count":43,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T00:00:00Z","timestamp":1789344000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      Although ovulation synchronization protocols effectively control the timing of ovulation, pregnancy success remains highly variable among individual cows. The periovulatory ovarian responses associated with subsequent pregnancy outcome following synchronization remain poorly characterized in\n                      <jats:italic>Bos indicus<\/jats:italic>\n                      beef cattle. Therefore, this exploratory longitudinal study characterized individual ovarian sonographic and hormonal responses during an Ovsynch synchronization protocol and evaluated associations with pregnancy outcome in Peranakan Ongole cows.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Ten multiparous Peranakan Ongole cows without apparent reproductive abnormalities and body condition scores of 2.5\u20133.0 (5-point scale) were synchronized using a single Ovsynch protocol. Ovarian sonographic characteristics and circulating estradiol and progesterone concentrations were evaluated throughout the periovulatory period, and pregnancy was determined by ultrasonography.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Nine of the ten cows ovulated following the synchronization protocol, and pregnancy was confirmed in four cows. Most post-ovulatory ovarian and hormonal variables showed weak associations at the 72-h post-ovulatory assessment. Baseline ovarian characteristics showed no detectable associations with post-ovulatory responses, whereas pre- and post-ovulatory estradiol concentrations remained positively associated. Among the post-ovulatory variables evaluated, corpus hemorrhagicum diameter showed the strongest nominal association with pregnancy outcome. Combining corpus hemorrhagicum diameter with largest follicle diameter or corpus hemorrhagicum echogenicity also showed nominal associations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>These preliminary findings suggest that early post-ovulatory ovarian characteristics, particularly corpus hemorrhagicum development, may be relevant to pregnancy outcome following synchronization.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fvets.2026.1920158","type":"journal-article","created":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T04:36:07Z","timestamp":1789360567000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Individual periovulatory ovarian responses associated with pregnancy outcome following an Ovsynch protocol in Peranakan Ongole cows"],"prefix":"10.3389","volume":"13","author":[{"given":"Sari Yanti","family":"Hayanti","sequence":"first","affiliation":[{"name":"Study Program of Veterinary Biomedical Sciences, Postgraduate School, IPB University","place":["Bogor, West Java, Indonesia"]},{"name":"Research Center for Animal Husbandry, Research Organization of Agriculture and Food, National Research and Innovation Agency (BRIN)","place":["Bogor, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad","family":"Imron","sequence":"additional","affiliation":[{"name":"Center for Livestock Breeding and Forage Feed Development, Ministry of Agriculture","place":["Sembawa, South Sumatra, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Santoso","family":"Santoso","sequence":"additional","affiliation":[{"name":"Research Center for Animal Husbandry, Research Organization of Agriculture and Food, National Research and Innovation Agency (BRIN)","place":["Bogor, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmad","family":"Adigunawan","sequence":"additional","affiliation":[{"name":"Study Program of Veterinary Biomedical Sciences, Postgraduate School, IPB University","place":["Bogor, West Java, Indonesia"]},{"name":"Center for Livestock Breeding and Forage Feed Development, Ministry of Agriculture","place":["Sembawa, South Sumatra, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rahma Isartina","family":"Anwar","sequence":"additional","affiliation":[{"name":"Research Center for Animal Husbandry, Research Organization of Agriculture and Food, National Research and Innovation Agency (BRIN)","place":["Bogor, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adelaide Jos\u00e9 Pereira","family":"Crist\u00f3v\u00e3o","sequence":"additional","affiliation":[{"name":"Animal Health Department, Faculty of Agriculture, Universidade Nacional Timor Lorosa\u2019e (UNTL)","place":["Dili, Timor-Leste"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamad Agus","family":"Setiadi","sequence":"additional","affiliation":[{"name":"Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University","place":["Bogor, West Java, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Herdis","family":"Herdis","sequence":"additional","affiliation":[{"name":"Research Center for Animal Husbandry, Research Organization of Agriculture and Food, National Research and Innovation Agency (BRIN)","place":["Bogor, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bambang","family":"Purwantara","sequence":"additional","affiliation":[{"name":"Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University","place":["Bogor, West Java, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mokhamad Fakhrul","family":"Ulum","sequence":"additional","affiliation":[{"name":"Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University","place":["Bogor, West Java, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amrozi","family":"Amrozi","sequence":"additional","affiliation":[{"name":"Division of Reproduction and Obstetrics, School of Veterinary Medicine and Biomedical Sciences, IPB University","place":["Bogor, West Java, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,14]]},"reference":[{"key":"ref1","first-page":"1","volume-title":"Encyclopedia of Livestock medicine for large animal and Poultry 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