{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T00:00:32Z","timestamp":1771632032693,"version":"3.50.1"},"reference-count":59,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2012,6,1]],"date-time":"2012-06-01T00:00:00Z","timestamp":1338508800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":["rep.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2012,6,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The ovaries of eight African elephant foetuses and their mothers between 2 and 22 months of gestation, and those of two cycling and two lactating elephants, were examined grossly, histologically and immunocytochemically, with emphasis on the development and regression of accessory corpora lutea (CL) of pregnancy and the steroidogenic capacities of the accessory CL and the foetal ovaries. The results supported recent findings that the accessory CL form as a result of luteinisation, with and without ovulation, of medium-sized follicles during the 3-week inter-luteal period of the oestrous cycle. They enlarge significantly and become steroidogenically active around 5 weeks of gestation, probably in response to the placental lactogen which is secreted by the implanting trophoblast of the conceptus. The large luteal cells stained strongly for 3\u03b2 hydroxysteroid dehydrogenase (3\u03b2HSD) activity throughout the 22-month gestation period although they showed vacuolation and other degenerative changes in the final months of gestation coincident with hypertrophy and hyperplasia of 3\u03b2HSD-positive interstitial cells in the foetal gonads. It is proposed that the progestagens secreted by the enlarged gonads of the elephant foetus may function both to assist the maternal ovaries in supporting the pregnancy state and to induce torpor and intrauterine immobility of the rapidly growing foetus.<\/jats:p>","DOI":"10.1530\/rep-12-0032","type":"journal-article","created":{"date-parts":[[2012,3,28]],"date-time":"2012-03-28T23:33:04Z","timestamp":1332977584000},"page":"845-854","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-1","source":"Crossref","is-referenced-by-count":15,"title":["Luteal maintenance of pregnancy in the African elephant (\n                    <i>Loxodonta africana<\/i>\n                    )"],"prefix":"10.1093","volume":"143","author":[{"given":"F J","family":"Stansfield","sequence":"first","affiliation":[{"name":"The Elephant Research and Conservation Unit Sav\u00e9 Valley Conservancy, Chiredzi, Harare, Zimbabwe 2Faculty of Veterinary Science University of Pretoria, Onderstepoort 0110 Gauteng P Bag X 04, South Africa and 3The Paul Mellon Laboratory \u2018Brunswick\u2019, 18 Woodditton Road, Newmarket, Suffolk CB8 9BJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"W R","family":"Allen","sequence":"additional","affiliation":[{"name":"The Elephant Research and Conservation Unit Sav\u00e9 Valley Conservancy, Chiredzi, Harare, Zimbabwe 2Faculty of Veterinary Science University of Pretoria, Onderstepoort 0110 Gauteng P Bag X 04, South Africa and 3The Paul Mellon Laboratory \u2018Brunswick\u2019, 18 Woodditton Road, Newmarket, Suffolk CB8 9BJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2012,6,1]]},"reference":[{"key":"2026010712560665300_bib1","first-page":"405","article-title":"The influence of fetal genotype upon endometrial cup development and PMSG and progestagen production in equids","volume":"Supplement 23","author":"Allen","year":"1975","journal-title":"Journal of Reproduction and Fertility"},{"key":"2026010712560665300_bib2","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1098\/rstb.2006.1831","article-title":"Ovulation, pregnancy, placentation and husbandry in the African elephant (Loxodonta africana)","volume":"361","author":"Allen","year":"2006","journal-title":"Philosophical Transactions of the Royal Society B"},{"key":"2026010712560665300_bib3","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1530\/jrf.0.0290313","article-title":"The origin of the equine endometrial cups I. 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