final Flashcards
define embryo
similar between species; can’t distinguish species
define fetus
can determine species
how can age be estimated
crown-rump length
length of femur/radius/tibia
circumference of head
what make us the factors of fetal growth
genetics
environment
fetal hormones
what makes up genetics
species
breed
litter size (increased offspring=slower growth rate)
genotype (certain lines of animals grow faster)
what makes up the environment
from the mother:
nutrition
parity (number of previous pregnancies)
from placenta:
blood flow
size
what makes up fetal hormones
thyroid- skeletal and muscular development
insulin- increased energy substrate availability and stimulates placental growth
growth hormone- stimulates fetal growth
where does P4 come from
the CL and the placenta
what type of P4 do sows use
P4 from the placenta
what other species don’t have P4 from the placenta
bitch
queen
alpaca
rabbit
goat
what causes an increase in prenatal loss
nutritional stress
disease of reproductive tract
endocrine imbalance
aging of gametes prior to fertilization
adrenal changes with age
what is the orientation of the fetus
begins on back and reorients so front feet and head will exit first
define breech
rump exits first
describe stage one of labor
initial myometrium contraction
progesterone block is removed to increase E2 and PGF2a
pressure applied to cervix
describe stage two of labor
delivery of fetus
mediated by oxytocin release
relaxin from CL/placenta softens cervix
E2 increases mucous in cervix
describe stage three of labor
delivery of fetal membrane
vasoconstriction of chorionic villi allow for separation
continues myometrial contractions
time differs between species
define dystocia. what can cause it
difficult birth
excessive fetal size
abnormal presentations
twins
fescue toxicosis
what are perinatal fetal changes
cardiovascular
thermoregulatory
energy metabolism
immune response
describe the cardiovascular perinatal change
ductus arteriosis, foramen ovale, and ductus venosus all close
define ductus arteriosis
blood from dam goes straight into the fetus’ heart
define foramen ovale
connects left and right ventricles of fetus
define ductus venosus
brings blood directly to fetus’ liver
describe the thermoregulatory perinatal change
regulates body temp
increase metabolism
brown fat
describe the energy metabolism perinatal change
until suckling, relies on its own storage of glycogen
describe the immune response perinatal change
no protective antibodies
passive immunity from mother
gut permeable antibodies in colostrum
define involution
uterus shrinks
how much does pregnany rate increase after the first birth?
2nd?
3rd?
4th?
35%
50%
73%
74%
define amenorhea
absence of menstruation
describe mare’s special postpartum estrus
foal heat (6-13 days post-partum)
fertility depends on body condition
describe sow’s special postpartum estrus
anovulatory estrus (3-5 days post-farrowing)
weaning induces estrus 3-5 days later
what does the Y chromosome contain
SRY gene which causes male reproductive tract to develop
define anti-mullerian hormone
from the sertoli cells and causes degeneration of the paramesoneptiric ducts
what do the testis attach to before descending
the gubernaculum
what surrounds the testis
visceral vaginal tunica and parietal vaginal tunica
where do the testis pass through
inguinal ring
define cryptorchidism
undescended testicles
can be unilateral or bilateral
produce testosterone, but infertile
heritable
define freeman
female born twin to a bull
placental membranes fuse, meaning hormones are shared
what hormone do the freemans share
milieu
what does milieu do
testosterone increased in females
anti-mullenan hormone
chimeric (both contain SRY)
female repro tract does not develop
infertile female
