{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:00:17Z","timestamp":1760234417666,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,5,14]],"date-time":"2021-05-14T00:00:00Z","timestamp":1620950400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Balikesir University, Scientific Research Unit, Turkey","award":["2015\/89"],"award-info":[{"award-number":["2015\/89"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Effect of one-day delaying progesterone administration at the beginning of 5-day Cosynch protocol was investigated in Holstein heifers for the first artificial insemination (AI). Heifers received a synchronized ovulation and timed AI (TAI) with CIDR inserted on day (d) 0 (CIDR-5; n = 206) or d 1 (CIDR-4; n = 192). In both group, GnRH was administered on d 0 followed by a single PGF2\u03b1 injection and CIDR removal five days later from GnRH. On d 8, TAI and GnRH administration were concurrently conducted. Heifers detected in estrus up to 24 h prior to TAI were inseminated without GnRH administration. Rates of ovulation, accessory CL formation and new dominant follicle development following initial GnRH injection did not differ between groups. P\/AI did not differ between CIDR-4 (44.3%, [85\/192]) and CIDR-5 (51.9%, [107\/206]) groups, respectively. Pregnancy per AI (P\/AI) was significantly (p &lt; 0.01) declined as heifers\u2019 age (12\u201313, 14, 15, 16 and17\u201321 months) proceeded in CIDR-4 group (55.6%, 52.1%, 37.9%, 35.7%, 32.4%) compared to those in CIDR-5 group (60.0%, 50.0%, 53.9%, 51.5%, 46.2%) respectively. In conclusion, there is no benefit for delaying CIDR administration in 5-day Cosynch protocol in dairy heifers. However, higher P\/AI in CIDR-5 group in older heifers can be considered for reproductive management.<\/jats:p>","DOI":"10.3390\/ani11051402","type":"journal-article","created":{"date-parts":[[2021,5,14]],"date-time":"2021-05-14T10:54:22Z","timestamp":1620989662000},"page":"1402","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of One-Day Delaying CIDR Administration in 5-Day Cosynch Protocol in Dairy Heifers"],"prefix":"10.3390","volume":"11","author":[{"given":"S\u00fckr\u00fc Metin","family":"Pancarci","sequence":"first","affiliation":[{"name":"Faculty of Veterinary Medicine, Bal\u0131kesir University, 10145 Bal\u0131kesir, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"\u00d6rsan","family":"G\u00fcng\u00f6r","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Burdur Mehmet Akif Ersoy University, 15030 Burdur, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Osman","family":"Harput","sequence":"additional","affiliation":[{"name":"UNSPED Dairy Farm Incorporation, 70500 Karaman, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oguz","family":"Calisici","sequence":"additional","affiliation":[{"name":"Clinic for Cattle, University of Veterinary Medicine Hannover (Foundation), 30173 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1017\/S1751731114000755","article-title":"Heifer fertility and carry over consequences for life time production in dairy and beef cattle","volume":"8","author":"Wathes","year":"2014","journal-title":"Animal"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Eastham, N.T., Coates, A., Cripps, P., Richardson, H., Smith, R., and Oikonomou, G. 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