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The deposition of calcium in the placenta as a result of placental abruption, infarction, or aging. This form of placental degeneration may contribute to preterm labor and fetal distress. See: abruptio placentae; infarction
See also: calcification
pertaining to or emanating from placenta.
the placental separation of maternal and fetal blood which varies in its structure and permeability between the species. In general the more layers of cells between the two circulations the less permeable the membrane. In none of the domestic animals are significant amounts of immune globulins or erythrocyte antigens passed through the membranes unless the epithelium is damaged. See also placenta.
accumulations of mineral deposit especially around the vessels and in the allantois, a normal occurrence in most species.
the allantoic and amniotic cavities; called also amniotic and allantoic sac.
edema of the placenta, without necessarily any involvement of the fetus.
the placenta in all species produces estrogens and progesterone. In the cow it also produces lactogen, a hormone that influences structural and functional aspects of milk production. In the mare the endometrial cups produce pmsg (now called eCG) which assists in the maintenance of pregnancy. The equine, feline and primate placentae also produce relaxin which has a similar action.
the placenta of a viable fetus, escaped from the genital tract, can implant successfully to the peritoneum.
a placental hormone present in the cow's peripheral circulation at about 160 days of pregnancy; thought to have prolactin and growth-hormone capabilities.
are normal structures on the amnion in most species. They are foci of squamous epithelium.
manual removal per vagina, detaching the placenta from each caruncle in turn.
placental transfer of immunoglobulins
see placental barrier (above) and passive immunity.