{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T18:50:04Z","timestamp":1791312604875,"version":"4.3.1"},"reference-count":33,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2024,6,21]],"date-time":"2024-06-21T00:00:00Z","timestamp":1718928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Council of Thailand (NRCT)","award":["N42A660892"],"award-info":[{"award-number":["N42A660892"]}]},{"name":"90th Anniversary of Chulalongkorn University Scholarship","award":["N42A660892"],"award-info":[{"award-number":["N42A660892"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>This study investigated the gross morphology of reproductive organs and oxytocin receptor distribution across different parities in hyperprolific sows. A total of thirty-two reproductive organs from Landrace \u00d7 Yorkshire crossbred sows were categorized into three groups based on parity numbers: 1 (n = 10), 2\u20135 (n = 12), and \u22656 (n = 10). All sows were culled due to management problems, and none had reproductive disorders. A gross morphology examination of the ovaries, uterus, and the rest of the reproductive tract was conducted. Using immunohistochemistry, the levels of oxytocin receptor were evaluated in five layers of the uterus, the epithelial, superficial glandular, deep glandular, and circular and longitudinal smooth muscles of the myometrium, and were quantified using an H-score. On average, the age and body weight of sows and the total number of piglets born per litter were 799.8 \u00b1 327.8 days, 213.2 \u00b1 31.7 kg, and 15.5 \u00b1 4.8, respectively. The numbers of ovulations in sows in parity number 1 (19.9 \u00b1 2.4) were lower than those in sows in parity numbers 2\u20135 (29.7 \u00b1 2.0, p = 0.004) and \u22656 (27.7 \u00b1 2.1, p = 0.022). The uterine weights of sows in parity number 1 (902.9 \u00b1 112.5 g) were lower than those of parity numbers 2\u20135 (1442.1 \u00b1 111.8 g, p = 0.001) and \u22656 (1394.3 \u00b1 125.1 g, p = 0.004). The length of the uterus in sows with parity number 1 (277.9 \u00b1 26.1 cm) was shorter than those in sows with parity numbers 2\u20135 (354.6 \u00b1 25.9 cm, p = 0.033) and tended to be shorter than those in sows with parity numbers \u2265 6 (346.6 \u00b1 29.0 cm, p = 0.068). The immunolocalization of oxytocin receptors could be detected in various parts of the porcine endometrium and myometrium. Among the five tissue layers of the uterus, the H-score of oxytocin receptors in the deep uterine glands was greater than in the superficial uterine glands (p = 0.023) and the circular muscle layer of the myometrium (p = 0.011), but it did not differ from the epithelial layer of the endometrium (p = 0.428) or the longitudinal muscle layer of the myometrium (p = 0.081). Sows with parity numbers \u2265 6 had a lower oxytocin receptor H-score than those with parity numbers 1 (p &lt; 0.001) and 2\u20135 (p &lt; 0.001). In conclusion, these data emphasize the notable variations in several reproductive parameters and the levels of oxytocin receptor within the uterus of hyperprolific sows. Across the majority of uterine tissue layers, there was a marked decrease in the H-score of the oxytocin receptor in the older sows.<\/jats:p>","DOI":"10.3390\/ani14131846","type":"journal-article","created":{"date-parts":[[2024,6,21]],"date-time":"2024-06-21T11:10:28Z","timestamp":1718968228000},"page":"1846","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Exploring Hyperprolific Sows: A Study of Gross Morphology of Reproductive Organs and Oxytocin Receptor Distribution across Parities"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4458-0433","authenticated-orcid":false,"given":"Yosua Kristian","family":"Adi","sequence":"first","affiliation":[{"name":"Centre of Excellence in Swine Reproduction, Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Department of Reproduction and Obstetrics, Faculty of Veterinary Medicine, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9856-1847","authenticated-orcid":false,"given":"Preechaphon","family":"Taechamaeteekul","sequence":"additional","affiliation":[{"name":"Centre of Excellence in Swine Reproduction, Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sawang","family":"Kesdangsakonwut","sequence":"additional","affiliation":[{"name":"CU-Animal Fertility Research Unit, Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9554-7436","authenticated-orcid":false,"given":"Paisan","family":"Tienthai","sequence":"additional","affiliation":[{"name":"Department of Anatomy, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3294-8301","authenticated-orcid":false,"given":"Roy N.","family":"Kirkwood","sequence":"additional","affiliation":[{"name":"School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, SA 5371, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7000-4371","authenticated-orcid":false,"given":"Padet","family":"Tummaruk","sequence":"additional","affiliation":[{"name":"Centre of Excellence in Swine Reproduction, Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1002\/mrd.23661","article-title":"Managing prolific sows in tropical environments","volume":"90","author":"Tummaruk","year":"2023","journal-title":"Mol. 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