{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T22:05:21Z","timestamp":1793052321802,"version":"4.5.0"},"reference-count":48,"publisher":"CSIRO Publishing","issue":"3","license":[{"start":{"date-parts":[[2025,5,27]],"date-time":"2025-05-27T00:00:00Z","timestamp":1748304000000},"content-version":"vor","delay-in-days":6321,"URL":"https:\/\/doi.org\/10.1071\/journalslicense"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2008,3,11]]},"abstract":"<jats:p>Higher systemic progesterone in the immediate post-conception period is associated with an increase in embryonic growth rate, interferon-tau production and pregnancy rate in cattle. The objective of this study was to examine the effect of increasing progesterone concentration on Day 3 on subsequent embryo survival and development. Oestrus (Day 0) was synchronised in beef-cross heifers (n = 210) and approximately two-thirds of the heifers were inseminated with semen from a proven sire, while the remainder were not inseminated. In order to produce animals with divergent progesterone concentrations, half of the animals received a progesterone-releasing intravaginal device (PRID) on Day 3 of the oestrous cycle, which was left in situ until slaughter. The four treatment groups were: (i) pregnant, high progesterone; (ii) pregnant, normal progesterone; (iii) non-pregnant, high progesterone; and (iv) non-pregnant, normal progesterone. Animals were blood-sampled twice daily from Days 0 to 8 and once daily thereafter until slaughter on Days 5, 7, 13 or 16, corresponding to the 16-cell stage, the blastocyst stage, the beginning of elongation and the day of maternal recognition of pregnancy, respectively. Embryos were recovered by flushing the tract with phosphate-buffered saline and characterised by stage of development and, in the case of Days 13 and 16, measured. Data were analysed by mixed models ANOVA, Chi-square analysis and Student\u2019s t-test where appropriate. Insertion of a PRID on Day 3 increased (P &amp;lt; 0.05) progesterone concentrations from Day 3.5 onwards. There was no difference between treatments in the proportion of embryos at the expected stage of development on Days 5 or 7 (P &amp;gt; 0.05). While not significantly different, the proportion of viable embryos recovered was numerically greater in the high progesterone group on both Day 13 (58 v. 43%) and Day 16 (90 v. 50%). Elevation of progesterone significantly increased embryonic length on Day 13 (2.24 \u00b1 0.51 mm v. 1.15 \u00b1 0.16 mm, P = 0.034) and Day 16 (14.06 \u00b1 1.18 cm v. 5.97 \u00b1 1.18 cm, P = 0.012). In conclusion, insertion of a PRID on Day 3 of the oestrous cycle increased serum progesterone concentrations on subsequent days, which, while having no phenotypic effect on embryonic development on Days 5 or 7, was associated with an increase in embryonic size on Days 13 and 16.<\/jats:p>","DOI":"10.1071\/rd07204","type":"journal-article","created":{"date-parts":[[2008,3,10]],"date-time":"2008-03-10T23:49:51Z","timestamp":1205192991000},"page":"368-375","source":"Crossref","is-referenced-by-count":279,"title":["Effect of increasing progesterone concentration from Day 3 of pregnancy on subsequent embryo survival and development in beef heifers"],"prefix":"10.1071","volume":"20","author":[{"given":"F.","family":"Carter","sequence":"first","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"N.","family":"Forde","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P.","family":"Duffy","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.","family":"Wade","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T.","family":"Fair","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M. A.","family":"Crowe","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A. C. O.","family":"Evans","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D. A.","family":"Kenny","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. F.","family":"Roche","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P.","family":"Lonergan","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture, Food Science and Veterinary Medicine, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland."},{"name":"BCorresponding author. Email: pat.lonergan@ucd.ie"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"67","published-online":{"date-parts":[[2008,2,5]]},"reference":[{"key":"2025102818394625700_R1"},{"key":"2025102818394625700_R2"},{"key":"2025102818394625700_R3"},{"key":"2025102818394625700_R4"},{"key":"2025102818394625700_R5"},{"key":"2025102818394625700_R6"},{"key":"2025102818394625700_R7"},{"key":"2025102818394625700_R8"},{"key":"2025102818394625700_R9"},{"key":"2025102818394625700_R10"},{"key":"2025102818394625700_R11"},{"key":"2025102818394625700_R12"},{"key":"2025102818394625700_R13"},{"key":"2025102818394625700_R14"},{"key":"2025102818394625700_R15"},{"key":"2025102818394625700_R16"},{"key":"2025102818394625700_R17"},{"key":"2025102818394625700_R18"},{"key":"2025102818394625700_R19"},{"key":"2025102818394625700_R20"},{"key":"2025102818394625700_R21"},{"key":"2025102818394625700_R22"},{"key":"2025102818394625700_R23"},{"key":"2025102818394625700_R24"},{"key":"2025102818394625700_R25"},{"key":"2025102818394625700_R26"},{"key":"2025102818394625700_R27"},{"key":"2025102818394625700_R28"},{"key":"2025102818394625700_R29"},{"key":"2025102818394625700_R30"},{"key":"2025102818394625700_R31"},{"key":"2025102818394625700_R32"},{"key":"2025102818394625700_R33"},{"key":"2025102818394625700_R34"},{"key":"2025102818394625700_R35"},{"key":"2025102818394625700_R36"},{"key":"2025102818394625700_R37"},{"key":"2025102818394625700_R38"},{"key":"2025102818394625700_R39"},{"key":"2025102818394625700_R40"},{"key":"2025102818394625700_R41"},{"key":"2025102818394625700_R42"},{"key":"2025102818394625700_R43"},{"key":"2025102818394625700_R44"},{"key":"2025102818394625700_R45"},{"key":"2025102818394625700_R46"},{"key":"2025102818394625700_R47"},{"key":"2025102818394625700_R48"}],"container-title":["Reproduction, Fertility and Development"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/connectsci.au\/rd\/article-pdf\/20\/3\/368\/301840\/rd07204.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/connectsci.au\/rd\/article-pdf\/20\/3\/368\/301840\/rd07204.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T22:39:52Z","timestamp":1761691192000},"score":1,"resource":{"primary":{"URL":"https:\/\/connectsci.au\/rd\/article\/20\/3\/368\/48573\/Effect-of-increasing-progesterone-concentration"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2008,2,5]]},"references-count":48,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2008,3,11]]}},"URL":"https:\/\/doi.org\/10.1071\/rd07204","relation":{},"ISSN":["1031-3613","1448-5990"],"issn-type":[{"value":"1031-3613","type":"print"},{"value":"1448-5990","type":"electronic"}],"subject":[],"published":{"date-parts":[[2008,2,5]]}}}