Test 4: lecture 6 pregnancy Flashcards
Monotocous
1 offspring at birth
Multiparous
> 1 pregnancy and parturition
> 1 offspring at birth (litter)
Nulliparous
never pregnant
pluriparous
> 1 pregnancy and parturition
polytocous
litter bearers
first pregnancy
primiparous
uniparous
1 pregnancy and parturition
1 offspring at birth
viviparous
offspring delivered alive
organogensis
very early in pregnancy from embryo→ fetus
ewe 12-34 days
cow 12-45 days
mare 12-60 days
gestation length for cow
280
gestation length for mare
340
gestation length for ewe
146
gestation length for doe
146
sow gestation length
114
bitch gestation length
63
queen gestation length
63
parts of the oviduct
infundibulum
ampulla (where fertilization takes place)
isthmus
2 cell embryo
blastomere
stage of division of embryo
zygote
blastomere (2 Cell)
4-8 morula
blastocyst (fluid cavity and tight junctions on periphery(trophoblast), gap junctions internal cells (ICM))
hatching from ZP and implantation
what happens to hatched blastocyst in sheep cattle and pigs
elongated→ filamentous structure → increases surface area to allow uterus to see
maternal recognition of pregnancy
Process by which the pre-attachment conceptus signals its presence to the dam. The must occur before luteolysis or the female will return to estrus.
CL must be preserved to maintain pregnancy
normal luteolysis
if not pregnant the uterus will secrete ___
PGF2 alpha
in cow, ewe and sow the vein will transfer PGF to the uterine artery and cause luteolysis of the non pregnant CL
CL released oxytocin → if there is enough oxytocin the uterus will release PGF
___ will prevent oxytocin from CL from binding to receptors during pregnancy
interferon (IFN T)
In cows and sheep
___ prevents luteolysis in sows
estradiol (estrogen produced by the blastocyst)
E2 will force PGF into the lumen of the uterus instead of into the blood→ will lead to contractions of the uterus that moves the blastocyst around
in sows how many embryo needed for maternal recognition
4
evenly distributed between both horns
___ helps with maternal recognition in the mare
migration all over the uterus
small or large amounts of PGF will cause luteolysis in mares and cows
cow, ewe and sow → large amounts
mare → small amounts
what does progesterone do?
Histotrophic secretion
- Closes cervix
- Increases uterine tone
- Suppresses myometrial activity
progesterone made by CL
what animals are not luteal dependent
mare, ewe and cow
CL stops producing progesterone some time during pregnancy and the placenta will produce progestogens to maintain pregnancy
human chorionic gonadotropin
HCG → has LH activity→ stimulate ovulation
human and cow
7-9 days days after implantation
- Luteotropic –LH activity
- Responsible for maternal recognition of pregnancy
Basis of most early pregnancy tests for women
equine chorionic gonadotropin is produced by
chorionic girdle → borrow into endometrium and female body will attack and around 120 days will slough off
40-120 days of gestation
During early gestation cell from the chorionic girdle of the embryo burrow into the endometrium of the mare and form endometrial cups. These cups are arranged in a circle. The cups produce equine chorionic gonadotropin which is associated with the formation of secondary corpora lutea. The mare mounts an lymphocytic immune response to the cups and they are destroyed. ECG concentrations are elevated in the pregnant mare from day 40 to 120 days of gestation.
ECG can be administered to ewes to stimulate multiple ovulations.
prostaglandins Interact with___ to regulate uterine blood flow
steroids and catecholamines
PGE produced by the equine conceptus controls___ through the isthmus of the oviduct
transport of the equine embryo
lactogen
produced to tell female to divert energy to the fetus and develop mammary gland
Placental lactogen is a polypeptide hormone produced by the placenta in cows, sheep, does, women, mice and rats. Placental lactogen is also known as chorionic somatomammotropin. Placental lactogen has prolactin and growth hormone-like activity. During pregnancy placental
lactogen influences maternal metabolism to direct nutrients to the fetus, promoting growth of the fetus. Placental lactogen also has lactogenic activity and stimulates mammary gland development. The somatotropic/lactogenic activity of this hormone varies between species.
relaxin
Produced by the placenta and ovary
- Women, mares, queens, bitches, sows
- Softens and relaxes pelvic ligaments near term
- Aid in expulsion of the fetus
placentation in horse
Progesterone stimulates synthesis of glycocalyx
- Endometrium covered by MUC-1 (prevents embryo from attaching)
- Progesterone receptors down-regulate
- MUC-1 decreases
- Allows conceptus to contact endometrium
- Attachment by interdigitation of trophoblastic and endometrial microvilli
- Resulting in epitheliochorial placentation
ruminants placentation
Binucleate cells form
- Fuse with endometrial epithelium to form multinucleate cells (syncytium)
- Chorion form papillae that project into uterine glands
- Villi (cotyledons) form over caruncles to form placentomes
Binucleate cells form from trophoblast cells starting on day 17. The binucleate cells migrate and fuse with the underlying endometrial epithelium to form multinucleate cells or a syncytium. The cells may be involved in the immunologic protection of the conceptus and transfer of placental lactogen (produced by binucleate cells) to the maternal circulation. Early on the chorion form papillae that project into the lumen of the uterine glands and provide an anchor and absorptive surface. More complex microvilli (cotyledons) form over the caruncles to form the placentomes.
cotyledon and caruncle =
placentomes → ruminants
binucleate cells form and fuse with endometrial epithelium to form ___
multinucleate cells (syncytium)
ruminants
function of the fetal membrane
Protection • Nutrient gas exchange • Substance transfer • Fetal wastes • Synthesis enzymes and hormones • Respiration
chorion
trophoblast and mesoderm (2 layer)
allantochorion
trophoblast, mesoderm and allantosis
development of the allantois
what kind of animals have a diffuse placentation
sow and mare
___ have convex cotyledonary placentation
___ have concave
cow and giraffe
sheep and goat
what kind of placenta does a dog have
zonary placentation
what kind of placenta for human
discoidal placenta
epitheliochorial
6 layers of tissue
no AB exchange
very little damage to endometrium at birth
endotheliochorial
dogs and cats
5 cell layers
some Ig pass
some damage to endometrium during birth
hemochorial
humans
3 layers
fetal tissue bathed in maternal blood
Ig pass easily
deciduate
Maternal epithelium and submucosa are lost at parturition leaving a denuded endometrium
(humans)
Indeciduate
Fetal membranes are expelled after birth leaving an intact epithelium.
(horses and cattle)
how do epitheliochorial get Ig
no transfer (6 layers)
get from colostrum
INF T will cause
decrease lymphocytes → prevent mother from attacking fetus
___ will inhibit T lymphocyte activation
TGF beta
PGE2
uterine serpin
progesterone
___ bind and cause lymphocyte death to protect fetus
Fas ligand
Fusion of pronuclei
syngamy
4-8 cells
morula → usually passed to uterus
cells on outside of blastocyst form __
tight junctions
trophoblast → fetal membrane
Na pump cause water to fill blastocoele
part of the chorionic girdle that produces eCG from day 40-120 of 340 days in horses
red dots are ___
on ___ side of the ___
attach to the ___ forming the ___
cotyledons
chorion side of the placenta
attach to the caruncle of the endometrium forming the placentomes
area outside red
intercotyledon area
