Pig
What is the pig placenta based on all classification
Diffuse, epitheliochorial, nondeciduate, smooth/fold
What is the horse placenta based on all classifications
Diffuse, epitheliochorial, nondecidiuate, villous
classify ruminant placenta
Cotyledonary, epitheliochorial (most), nondeciduate/ delayed deciduate, villous
Classify carnivore placenta
Zonary, endotheliochorial, deciduate, lamellar/ labyrinth
Horses have a long or short umbilical cord
Long- foal can stand after birth
At time of birth what happened to amnion
Fetus ruptures amnion at time of birth
The diffuse placenta of a horse contains three “micro” structures. What are they
Microplacentomes, microcotyledons, microcaruncels
Placentome=
Caruncle + cotyledon
What is the fetal component of the placenta labyrinth
Chorion
The spongy layer glands are the site of what that occurs at birth
Site where separation of placenta occurs at birth
What is the embryo/fetus to placenta ratio
Each embryo/fetus has its own placenta
Where is amnion in a horse placenta
Amnion is free floating (no Fusion to chorion)
remains around fetus after birth, attendant must remove to prevent suffocation of foal
What is the name of the “binucleated giant cells” in placenta of ruminants
Diplokaryocytes- originate from cytotrophoblasts
What are the maternal component of the labyrinth
Endometrial blood vessels
What is the hippomane in horse placenta composed of
Cellular debris and GAGs
What must occur by day 12 of gestatoon to prevent abortion of fetuses
Must be 2 fetuses in each horn by day 12
What are three other structures of the placenta unique to the horse
“Cervical star”, Hippomane, endometrial cups
What other cells are present at the surface of chorion
Simple cytotrophoblasts (mononuclear trophpoblasts)
What four things are included in the chorion component of placenta labyrinth
Cytotrophoblasts, syncytiotrophoblasts, fetal capillaries, and mesenchyme
Region at the junction of yolk sac and allantois
trophoblasts leave the chorion in this region and invade into endometrium to form endometrial cup
Since pig placenta is epitheliochorial, what is at the surface of the chorion
Simple trophoblasts at the surface of the chorion
What are endometrial cups
Discrete areas in endometrium of uterus, source of chorionic gonadotropin (eCG), chorionic girdle
What is the difference in shape of the placentome of cattle vs sheep and goats
Convex in cattle, concave in sheep and goats
What is the marginal hematoma and what happens here
Lateral margins of labyrinth, “brown border” in cats
maternal blood degraded by trophoblats
In a low mag of uterus and placenta in transverse orientation, what can you see
Placenta labyrinth, spongy layer Glands, supraglandular layer, deep glandular layer