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The Role of Ovine Conceptus Secretory Proteins in the Establishment of Pregnancy

  • Fuller W. Bazer
  • J. L. Vallet
  • C. J. Ashworth
  • R. V. Anthony
  • R. M. Roberts
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 230)

Abstract

Sheep (Ovis aries) that are not pregnant have recurring estrous cycles of about 17 days’ duration during the breeding season, i.e., August through December to January. The first day of behavioral estrus is designated Day 0 with ovulation occurring about 30h after onset of estrus and the ovulatory surge of Luteinizing Hormone (LH). The estrous cycle is characterized by growth (Days 4–12) and then regression (luteolysis) of the corpus luteum (CL). Luteolysis begins on about Day 15 after onset of estrus. Prostaglandin F2-alpha (PGF), produced by the uterine endometrium, is the uterine luteolytic hormone in sheep (1). Beginning on Days 14 to 15 and continuing until the onset of the next period of estrus, PGF is released in a pulsatile manner. About 5 episodes of PGF release per 24h are required for luteolysis (2,3).

Keywords

Corpus Luteum Estrous Cycle Uterine Horn Oxytocin Receptor Uterine Endometrium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Fuller W. Bazer
    • 1
    • 2
  • J. L. Vallet
    • 1
    • 2
  • C. J. Ashworth
    • 1
    • 2
  • R. V. Anthony
    • 1
    • 2
  • R. M. Roberts
    • 1
    • 2
  1. 1.University of FloridaGainesvilleUSA
  2. 2.University of MissouriColumbiaUSA

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