{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,2]],"date-time":"2025-11-02T11:47:30Z","timestamp":1762084050117,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,23]],"date-time":"2022-12-23T00:00:00Z","timestamp":1671753600000},"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>After breeding or artificial insemination, especially with frozen\/thawed semen, mares often develop a persistent uterine inflammation, which is diagnosed by intra-uterine fluid accumulation. Here, we explored whether intra-uterine fluid accumulation affects corpus luteum function and tested the hypothesis that intra-uterine fluid accumulation after artificial insemination alters blood flow in the corpus luteum and plasma progesterone concentrations. A total of 40 Standardbred mares were artificially inseminated with frozen-thawed semen 30 to 36 h after induction of ovulation, and cases with or without intra-uterine fluid accumulation were detected by ultrasound 12 h after insemination. Luteal blood flow was measured by Power Doppler ultrasonography 3 and 6 days after ovulation, progesterone concentration was measured in peripheral plasma by ELISA 6 days after ovulation, and pregnancy was diagnosed by ultrasonography 14 days after ovulation. Luteal blood flow increased between 3 and 6 days after ovulation, but blood flow did not differ significantly between cases with (n = 28) and without (n = 25) intra-uterine fluid accumulation after insemination. Surprisingly, progesterone concentrations were higher in cases of intra-uterine fluid accumulation than cases without (9.3 \u00b1 1.1 vs. 6.6 \u00b1 0.5 ng\/mL, p = 0.048). Pregnancy was less likely in cases with intra-uterine fluid accumulation than in cases without (10\/28 vs. 17\/25, p = 0.019), and there was a negative correlation between the severity of intra-uterine fluid accumulation and per cycle pregnancy rate. These data suggest that although intra-uterine fluid accumulation increases the secretion of progesterone, pregnancy is more dependent on uterine health than ovarian function.<\/jats:p>","DOI":"10.3390\/ani13010067","type":"journal-article","created":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T07:02:12Z","timestamp":1672124532000},"page":"67","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Effects of Intra-Uterine Fluid Accumulation after Artificial Insemination on Luteal Function in Mares"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1645-2111","authenticated-orcid":false,"given":"Francesca","family":"Freccero","sequence":"first","affiliation":[{"name":"DIMEVET, Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell\u2019Emilia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0127-4890","authenticated-orcid":false,"given":"Beatrice","family":"Mislei","sequence":"additional","affiliation":[{"name":"AUB INFA National Institute of Artificial Insemination, University of Bologna, Via Gandolfi 16, 40057 Cadriano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6276-2674","authenticated-orcid":false,"given":"Diego","family":"Bucci","sequence":"additional","affiliation":[{"name":"DIMEVET, Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell\u2019Emilia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8259-6458","authenticated-orcid":false,"given":"Francesco","family":"Dondi","sequence":"additional","affiliation":[{"name":"DIMEVET, Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell\u2019Emilia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6890-7272","authenticated-orcid":false,"given":"Gaetano","family":"Mari","sequence":"additional","affiliation":[{"name":"DIMEVET, Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell\u2019Emilia, Italy"},{"name":"AUB INFA National Institute of Artificial Insemination, University of Bologna, Via Gandolfi 16, 40057 Cadriano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1016\/0093-691X(94)90173-G","article-title":"Sperm-induced leucocytosis in the equine uterus","volume":"41","author":"Kotilainen","year":"1994","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/j.repbio.2016.06.002","article-title":"Evaluation of diagnostic methods in equine endometritis","volume":"16","author":"Katila","year":"2016","journal-title":"Reprod. 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