Bovine Bovine

Bovine

• Bovine

• 9 - 11 days

• Equine, Ovine

• 7 - 8 days

• Porcine

• 6 days

Ectoderm

• Ectoderm

• CNS
• Sense organs
• Mammary glands
• Sweat glands
• Skin
• Hair
• hooves

Yolk Sack

• Yolk Sack

• In birds to nourish embryo
• In mammal atrophies but source of blood cells and primordial germ cells

• Amnion

• Non-vascular, fluid filled
• Fluid produced by fetus
• Protective cushion
• Ruptures at birth (not breaking of water)

Allantois

• Allantois

• Blood vessels
• Fuses with chorion
• Allantochorion or chorioallantois
• Brings blood vessels to chorion

• Chorion

• Outermost membrane
• Attachment to mother

CL does not regress if not pregnant

• CL does not regress if not pregnant

• no uterine effect

• Psuedopregnancy

• CL last similar length as in pregnancy

Superficial

• Superficial

• Chorion lies opposed to uterine wall
• Farm animals

• Eccentric

• Chorionic sack in a uterine fold
• Rodent

• Interstitial

• Embryo digests part of uterine wall
• human

Deciduate

• Deciduate

• Eccentric, interstitial
• Rodent, human

• Indeciduate or Nondeciduate

• Superficial
• Farm animals

Cotelydonary - cow, sheep

• Cotelydonary - cow, sheep

• Diffuse - pig, horse

• Zonary - dog, cat

• Discoid - human

20% of fetal placenta

• 20% of fetal placenta

• Invade endometrium

• Source

• Placental lactogen
• Pregnancy specific protein B

Unique to ruminants

• Unique to ruminants

• Function uncertain

• Has been used to detect pregnancy

• Cattle, sheep, deer
• Can be used to detect pregnancy in cows after day 25

From both trophoblast and endometrium

• From both trophoblast and endometrium

• 5 to 10

• Form between days 35 to 60

• Produce equine chorionic gonadotropin (eCG, PMSG)

• Sloughed off after day 60

Fetal and maternal blood does not mix during gestation.

• Fetal and maternal blood does not mix during gestation.

• Mixing may occur at parturition and may result in antibodies against specific fetal blood type. Impacts future fetuses or neonates!!!

• Erythoroblastosis Fetalis – Human
• Antibodies cross placenta (Rh factor)
• Neonatal Isoerythrolysis – Cat and Horse
• Antibodies in colostrum and absorbed first 24 hr of neonate’s life