Pregnancy and Fetal Disorders

The Y chromosome ____ gene, testosterone and AMH are needed for proper male developement

SRY gene

What hormone is needed for the regression of the male tract and persistence of the female tract in a bipotential gonad?

female is the default (no hormones needed)

Sertoli cell ____ causes mullerian duct regression

AMH

Leydig cell testerone supports ________ which does what

wolffian ducts

masculinizes external genitalia

What is androgen insensitivity?

testes and AMH present, but external genitalia are female or ambiguous

(not responding to signals - phenotypically female)

What are disorders of sexual development?

any mismatch between genotype sex and gonadal and/or phenotypic sex

What is euploidy

the correct number of chromosomes in a species

XX or XY

What is a chimera

XX and XY in one animal

What is aneuploidy

an abnormal number of chromosomes

(XXY of X0)

What is freemartinism

- most common DSD

- male and female twins

- Chimeras (XX and XY) = male cells exchange with female due to mingling of placental blood supply

- hypoplastic uterus and ovaries

Explain euploidy with gene knockouts with polled intersex syndrome

- select for goats without horn gene

- horn gene next to testicular repressor gene

- testicular repressor gene gets deleted with the horn gene

- females born with testicles

Explain euploidy with gene knockouts with persistent mullerian duct syndrome

male miniature schnauzers with AMH receptor defect

- males with abnormal testicles attached to uterus

What is the main hormone of the placenta and where does it come from

Progesterone!

corpus luteum (dogs, cats, pigs, early in cattle)

endometrial cups and accessory CL early on (horses

What are the fetal membranes of the placenta

amnion (directly around fetus)

allantois

(layers the same in people - pic just to help visualize)

Compare the following placenta types: epitheliochorial, endotheliochoriol, hemochoriol

epitheliochorial: least placental invastion

endotheliochoriol

hemochoriol: most placental invasion

What placenta types requires the offspring to NEED colostrum

epitheliochorial

What is the cervical star

part of placenta that was up against the cervix

What is a hippomane

Allantoic calculi (cellular debris in cows/mares)

(normal!)

Are amniotic plaques normal?

yes

What is eponychium

rubbery covering on newborn foals

What is the epithelion?

skin covering to keep fluid in fetus and prevent osmosis

What is adventitial placentation?

The formation of additional placentomas (in ruminants) i. NOTE: this is considered a hyperplastic response to inadequacy of the placentomal surface area. This reduction of area is due to loss caruncles.

Not enough oxygen exchange!

What is umbilical cord knot? is this normal?

MUST see hemorrhage or edema to be pathologic

What is hydrops allantois?

chorioallantoic cavity filled with fluid

(problem with the placenta!)

What is hydrops amnion?

Buildup of fluid around fetus

Fetus can't swallow the fluid up

(problem with fetus)

When is a placenta considered retained in cows vs horses? who has it more serious

> 24 hrs cows

> 3 hrs mare

Mares can become septic! ensure the whole placenta came out

Fetal monster: appearance of conjoined twins

Fetal monster: appearance of amorphous globosus/ acardiac bovine twin

Fetal monster: appearance of schistosomus reflexus

What is the triad of causes for abortions

maternal

infectious

fetal

Abortion vs stillbirth

Abortion: death of fetus before term

stillbirth: death of term fetus

What happens with an abortion if there are multiple fetuses?

pregnancy continues

Fate of the fetus in abortion depends on what

1. timing

2. prescence of bacteria

What happens to an aborted fetus bacteria vs no bacteria

No bacteria: resorption or mummification

bacteria: fetal maceration or emphysematous fetus is stillborn (destroys soft tissue and leaves bones)

What are sources of infectous abortions (placentitis)

- venereal

- hematogenous

- ascending from cervix

Why should you always wear gloves when dealing with placentas?

many infectious agents of the placenta/repro tract are zoonotic

Appearance and causes of intercotyledonary placentitis

Appearance and causes of cotyledon and fetal lesions

Know the agents in the photo!

Partuition is started by increasing fetal ____ and falling levels of maternal ____

Partuition is started by increasing fetal cortisol and falling levels of maternal progesterone

What is dystocia caused by

- fetus too big

- birth canal is too small

Fetopelvic disproportion can predispose to?

uterine torsion and rupture due to fetal malposition

How can overconditioning cause dystocia

fat deposits in pelvic canal

What are typical gross findings on the fetus or dam with dystocia?