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Maternal Recognition of Pregnancy - Anatomy & Physiology (view source)
Revision as of 21:49, 13 September 2008
, 21:49, 13 September 2008→Sow
== Sow ==
== Sow ==
* The pig conceptus produces oestradiol as the signal for maternal recognition of pregnancy.
* Also, PGF2 is produced in significant quantities, but is rerouted into the uterine lumen.
* Oestradiol is produced 11-12 days after ovulation. This does not inhibit secretion of PGF2 , but causes it to be secreted in a different direction than in a cycling sow.
* It is secreted away from submucosal capillaries, towards the uterine lumen.
* Luminal PGF2 has little access to the circulation, and thus cannot cause luteolysis.
* Production of oestradiol not only prevents luteolysis, but serves to stimulate contractions of the uterine myometrium. This ensures distribution of the conceptuses with proper spacing along the uterine horns.
=== Conceptus ===
* The secretion of oestradiol occurs in the period of conceptus elongation.
* There must be at least two conceptuses in each uterine horn for pregnancy to be maintained.
* If they are not present in one uterine horn, PGF2 will be secreted in an endocrine fashion and luteolysis will occur, thus terminating the pregnancy.