{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T05:54:57Z","timestamp":1790402097518,"version":"4.1.0"},"reference-count":41,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,5,14]],"date-time":"2020-05-14T00:00:00Z","timestamp":1589414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"This research was supported by the Ministry of Science, Innovation and Universities, Spain (Grants: RYC-2014-15581 and AGL2017- 88329-R), and the Regional Government of Catalonia (2017-SGR-1229). J.C. was funded by the National Commission of Scientific Re","award":["RYC-2014-1558 & AGL2017-88329R \/ 2017-SGR-1229 \/ 2017\/72180128"],"award-info":[{"award-number":["RYC-2014-1558 & AGL2017-88329R \/ 2017-SGR-1229 \/ 2017\/72180128"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>In the donkey, artificial insemination (AI) with frozen-thawed semen is associated with low fertility rates, which could be partially augmented through adding seminal plasma (SP) and increasing sperm concentration. On the other hand, post-AI endometrial inflammation in the jenny is significantly higher than in the mare. While previous studies analyzed this response through recovering Polymorphonuclear Neutrophils (PMN) from uterine washings, successive lavages can detrimentally impact the endometrium, leading to fertility issues. For this reason, the first set of experiments in this work intended to set an in vitro model through harvesting PMN from the peripheral blood of jennies. Thereafter, how PMN, which require a triggering agent like formyl-methionyl-leucyl-phenylalanine (FMLP) to be activated, are affected by donkey semen was interrogated. Finally, we tested how four concentrations of spermatozoa (100 \u00d7 106, 200 \u00d7 106, 500 \u00d7 106 and 1000 \u00d7 106 spermatozoa\/mL) affected their interaction with PMN. We observed that semen, which consists of sperm and SP, is able to activate PMN. Whereas there was a reduced percentage of spermatozoa phagocytosed by PMN, most remained attached on the PMN surface or into a surrounding halo. Spermatozoa not attached to PMN were viable, and most of those bound to PMN were also viable and showed high tail beating. Finally, only sperm concentrations higher than 500 \u00d7 106 spermatozoa\/mL showed free sperm cells after 3 h of incubation, and percentages of spermatozoa not attached to PMN were higher at 3 h than at 1 h, exhibiting high motility. We can thus conclude that semen activates PMN in the donkey, and that the percentage of spermatozoa phagocytosed by PMN is low. Furthermore, because percentages of spermatozoa not attached to PMN were higher after 3 h than after 1 h of incubation, we suggest that PMN-sperm interaction plays an instrumental role in the reproductive strategy of the donkey.<\/jats:p>","DOI":"10.3390\/ijms21103478","type":"journal-article","created":{"date-parts":[[2020,5,15]],"date-time":"2020-05-15T10:53:59Z","timestamp":1589540039000},"page":"3478","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Seminal Plasma, Sperm Concentration, and Sperm-PMN Interaction in the Donkey: An In Vitro Model to Study Endometrial Inflammation at Post-Insemination"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1085-0039","authenticated-orcid":false,"given":"Jordi","family":"Mir\u00f3","sequence":"first","affiliation":[{"name":"Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, E-08193 Bellaterra (Cerdanyola del Vall\u00e8s), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henar","family":"Mar\u00edn","sequence":"additional","affiliation":[{"name":"Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, E-08193 Bellaterra (Cerdanyola del Vall\u00e8s), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0878-7819","authenticated-orcid":false,"given":"Jaime","family":"Catal\u00e1n","sequence":"additional","affiliation":[{"name":"Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, E-08193 Bellaterra (Cerdanyola del Vall\u00e8s), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8610-2734","authenticated-orcid":false,"given":"Marion","family":"Papas","sequence":"additional","affiliation":[{"name":"Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, E-08193 Bellaterra (Cerdanyola del Vall\u00e8s), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabrina","family":"Gacem","sequence":"additional","affiliation":[{"name":"Equine Reproduction Service, Department of Animal Medicine and Surgery, Faculty of Veterinary Sciences, Autonomous University of Barcelona, E-08193 Bellaterra (Cerdanyola del Vall\u00e8s), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2209-340X","authenticated-orcid":false,"given":"Marc","family":"Yeste","sequence":"additional","affiliation":[{"name":"Biotechnology of Animal and Human Reproduction (TechnoSperm), Institute of Food and Agricultural Technology, University of Girona, E-17003 Girona, Spain"},{"name":"Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, E-17003 Girona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1016\/j.cveq.2019.08.014","article-title":"Key Aspects of Donkey and Mule Reproduction","volume":"35","author":"Canisso","year":"2019","journal-title":"Vet. 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