{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T19:28:05Z","timestamp":1791228485374,"version":"4.1.0"},"reference-count":41,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,3,9]],"date-time":"2025-03-09T00:00:00Z","timestamp":1741478400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>If global warming persists, new strategies will be necessary to keep high-yielding dairy cows\u2019 reproduction at a thermo-neutral level. In this study, two years of data from around 2000 cooled cows from a dairy farm in northeastern Romania were analyzed. In both years, an automated cooling system was used to maintain the temperature\u2013humidity index (THI) within the range of 65\u201375 when environmental conditions exceeded the upper limit of this range. The univariate analysis shows that there may be a potential association between parity and the heat detection rate (p &lt; 0.25). Additionally, the analysis suggests possible associations between conception rate and season, parity, and 4 + AIs (p &lt; 0.25). These findings warrant further investigation through multivariate analysis. Summer season had the biggest impact (p = 0.001) on poor conception rate, according to the multivariate logistic regression analysis. Notably, the effects on conception rates extended into autumn (p = 0.004) in cooled high-yielding dairy cows. As expected, repeat breeding (4 + AIs) and parity (3 + lact.) impacted reproduction (p = 0.05). However, there was no association between OvSynch and OvSynch + GnRH on day 5 after AI and conception rate (p &gt; 0.05). According to data from the current study, we concluded that the current cooling systems need to be improved to maintain reproduction at a thermo-neutral level for high-yielding dairy cows.<\/jats:p>","DOI":"10.3390\/ani15060777","type":"journal-article","created":{"date-parts":[[2025,3,10]],"date-time":"2025-03-10T09:36:24Z","timestamp":1741599384000},"page":"777","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Impact of Season and OvSynch + GnRH on Day 5 After Artificial Insemination (AI) on the Heat Detection and Conception Rates of Cooled High-Yielding Holstein Cows"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9601-0788","authenticated-orcid":false,"given":"Silviu-Ionu\u021b","family":"Bor\u015f","sequence":"first","affiliation":[{"name":"Research and Development Station for Cattle Breeding Dancu, 707252 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vasile","family":"Vintil\u0103","sequence":"additional","affiliation":[{"name":"Research and Development Station for Cattle Breeding Dancu, 707252 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alina","family":"Bor\u015f","sequence":"additional","affiliation":[{"name":"\u201cIon Ionescu de la Brad\u201d Iasi University of Life Sciences, 700490 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3568-0811","authenticated-orcid":false,"given":"Viorel-Cezar","family":"Flori\u0219tean","sequence":"additional","affiliation":[{"name":"\u201cIon Ionescu de la Brad\u201d Iasi University of Life Sciences, 700490 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.theriogenology.2024.11.007","article-title":"Perspectives in cattle reproduction for the next 20 years\u2013A European context","volume":"233","author":"Pascottini","year":"2025","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"100847","DOI":"10.1016\/j.animal.2023.100847","article-title":"Review: Reproductive consequences of whole-body adaptations of dairy cattle to heat stress","volume":"17","author":"Rhoads","year":"2023","journal-title":"Animal"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"6660","DOI":"10.3168\/jds.2018-16011","article-title":"Influence of on-farm measurements for heat stress indicators on dairy cow productivity, female fertility, and health","volume":"102","author":"Gernand","year":"2019","journal-title":"J. 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