Lecture 19 Placentation and Maternal Recognition of PregnancyBlastulationHatchingConceptus GrowthDevelopment of Porcine Conceptuses from Day 10 to 12Elongated Day 15 Porcine ConceptusUterine Location of Elongating Ruminant BlastocystPig Intrauterine MigrationSlide 9Slide 10Transuterine Migration in the MareGastrulationSlide 13GastrulaSlide 15Germ LayersPlacenta FormationPowerPoint PresentationSlide 19Slide 20Placental MembranesPlacental Membranes (cont.)Maternal Recognition of PregnancyLuteal RegressionCL StatusRecognition of PregnancySlide 27Recognition of Pregnancy in the PorcineSlide 29Recognition of Pregnancy in the MareRecognition of Pregnancy in the HumanRecognition of Pregnancy in RodentsSlide 33ImplantantionTime of ImplantationType of ImplantationDegree of Tissue Loss at ParturitionCotelydonary PlacentaSlide 39Placental Attachment in RuminantDay 23 Migration of Bicnucleate Cells and Formation of SyncytiumBinuclear Giant CellsSlide 43Pregnancy Specific Protein BDiffuse PlacentaMicrocotelydonsEndometrial Cups in MareZonary Placenta (bitch, queen)Discoid Placenta (human)Cell Layers Separating Maternal and Fetal BloodHistological ClassificationImportant!!!!Lecture 19Placentation and Maternal Recognition of PregnancyAnimal Science 434John J. ParrishNa+[Na+]H2OZona PellucidaZona PellucidaTrophectodermTrophectodermInner Cell MassInner Cell MassBlastulationTight JunctionsTight JunctionsGap JunctionsGap JunctionsHatchingBovine»9 - 11 daysEquine, Ovine»7 - 8 daysPorcine»6 daysConceptus GrowthSphericalSphericalFilamentousFilamentousCow•Day 15, 1-2 mm•Day 18-19, 10-20 cmTubularTubularEmbryonic AreaEmbryonic AreaElongatingTrophoblastElongatingTrophoblastMare remains spherical!Mare remains spherical!Occurs in cow, pig and sheepDevelopment of Porcine Conceptuses from Day 10 to 125 mm Spherical10 mm Spherical15 mm Tubular150 mmFilamentousInner CellMassElongated Day 15 Porcine ConceptusEmbryoUterine Location of Elongating Ruminant BlastocystCorpusLuteumBovine and OvinePig Intrauterine Migration Day 5Pig Intrauterine MigrationDay 7Pig Intrauterine MigrationDay 12Embryos become fixedTransuterine migration is rare in cow and ewe!Transuterine migration is rare in cow and ewe!Transuterine Migration in the MareCorpusLuteumFixation on day 15 - 16Fixation can occur in either horn!Begins Day 10GastrulationBlastocoeleCavityEndodermEndodermInner Cell MassInner Cell MassTrophectodermTrophectodermFormation of Germ LayersGastrulationEndodermEndodermEndodermEndodermYolk SackYolk SackGastrulaEctodermEctodermEndodermTrophectodermTrophectodermGastrulaEctodermEctodermMesodermMesodermYolk SackYolk SackEndodermEndodermTrophectoderm (Chorion)ExtraembryonicCoelomExtraembryonicCoelomGerm LayersEctoderm»CNS»Sense organs»Mammary glands»Sweat glands»Skin»Hair»hoovesMesoderm»Circulatory»Skeletal»Muscle»Reproductive tracts»Kidneys»Urinary ductsEndoderm»Digestive »Liver»Lungs»Pancreas»Thyroid gland»Other glandsPlacenta FormationYolk SackYolk SackChorionEmbryonicEctodermEmbryonicEctodermMesodermMesodermTrophectodermAmniotic FoldsExtraembryonic CeolomExtraembryonic CeolomEndodermEndodermExtraembryonic CeolomExtraembryonic CeolomAmniotic FoldAmniotic CavityYolk SackYolk SackAllantoisAllantoisChorionYolk SackYolk SackExtraembryonic CeolomExtraembryonic CeolomChorionAmnionAmnionic CavityCarnuncleAllantoisAllantoisUterineLumenChorionAllantochorion(Chorioallantois)Allantois CavityAllantois CavityCotyledonAmniotic CavityAmnionYolkSackYolkSackPlacental MembranesYolk Sack»In birds to nourish embryo»In mammal atrophies but source of blood cells and primordial germ cellsAmnion»Non-vascular, fluid filled»Fluid produced by fetus»Protective cushion»Ruptures at birth (not breaking of water)Placental Membranes (cont.)Allantois»Blood vessels»Fuses with chorion•Allantochorion or chorioallantois•Brings blood vessels to chorionChorion»Outermost membrane»Attachment to motherMaternal Recognition of PregnancyLuteal RegressionPGF2(Equine)No Uterine Factor(human)PGF2(Bovine, Ovine,Porcine)CL StatusCL(+)Uterine PGF2 Filamentous Embryo(+)MaintainedCAMechanismsCL Regression•Luteolytic•No CL supportCL Maintenance•Antiluteolytic»Block PGF2effects•Luteotrophic»Stimulate progesterone production by CLMechanismsCL Regression•Luteolytic•No CL supportCL Maintenance•Antiluteolytic»Block PGF2effects•Luteotrophic»Stimulate progesterone production by CLRecognition of PregnancyConceptus Secretions•Proteins•SteroidsRecognition of Pregnancy in Bovine and OvineConceptus Secretions•Interferons•oIFN-•bIFN-Mechanism•Antiluteolytic•Inhibit oxytocin receptor synthesis•Inhibit PGF2 synthesisCritical Days•Bovine - 16 to 17•Ovine - 12 to 13Critical Days•Bovine - 16 to 17•Ovine - 12 to 13Recognition of Pregnancy in the PorcinePGF2PGF2PGF2PGF2PGF2PGF2E2E2E2E2E2E2E2E2E2E2E2E2Recognition of Pregnancy in the PorcineConceptus Secretions•EstradiolCritical Days11 to 12Critical Days11 to 12Mechanism•Antiluteolytic»Redirect PGF2»Requires 2 embryos per hornPGF2PGF2PGF2PGF2PGF2PGF2E2E2E2E2E2E2E2E2E2E2E2E2Recognition of Pregnancy in the MarePGF2PGF2Conceptus Secretion•?Critical Days10 to 14Critical Days10 to 14Mechanism•antiluteolyticRecognition of Pregnancy in the HumanHCGConceptus Secretes•HCGMechanism•luteotrophicCritical Days•8 to 12Critical Days•8 to 12Recognition of Pregnancy in RodentsRPLRPL•Luteotrophic•Antiluteolytic•Estrous cycle - 4 days•Mating induces prolactin»Maintenance of CL»Psuedopregnancy•Not Pregnant»Prl after day 7»PGF day 11»Estrus by day 17•Pregnant»RPL after day 7, P4»PGF day 11»RPL protects CL from PGFRecognition of PregnancyConceptus Secretions•Proteins•SteroidsINF-RPLHCGEstradiolINF-RPLHCGEstradiolImplantantionTime of ImplantationAttachment to UterusSpecies Beginning Completionpig 13 24cow 22 40sheep 15 28mare 24 - 40 95 - 100human 7 - 8 30Type of ImplantationSuperficial»Chorion lies opposed to uterine wall»Farm animalsEccentric»Chorionic sack in a uterine fold»RodentInterstitial»Embryo digests part of uterine wall»humanDegree of Tissue Loss at ParturitionDeciduate»Eccentric, interstitial»Rodent, humanIndeciduate or Nondeciduate»Superficial»Farm animalsCotelydonary PlacentaCowCowEweEweConcaveConvexEndometriumCaruncleCotelydon (Chorion)90 - 10070 - 120Cotelydonary
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