Exam 3 - Teratogens, Obstetrics, Mammary Glands Flashcards
what is a critical period
single agent can induce dramatically different diseases at different stages of gestation
in what stage of development do majority of defects occur
organogenesis
bluetongue virus teratogenic effect
hydranencephaly
akabane virus or schmallenberg virus teratogenic effects
arthrogryposis
hydranencephaly
what are the two lesions of border disease virus
demyelination = tremors
poor wool quality
what are the biotypes of BVDV
non-cytopathogenic if infected 60-120 days
cytopathogenic - infection throughout pregnancy
what biotype of BVDV is responsible for persistently infected calves
non-cytopathogenic
which biotype of BVDV is the virus detectable at birth NOT antibodies
non-cytopathogenic (virus positive)
which biotype of BVDV is Ab positive but virus negative at birth
cytopathogenic (Ab positive)
what hormone is declining with parturition?
progesterone
length of stage I of parturition in the dog
6-12 hours
up to 36 hours
length of stage I of parturition in the cat
1-24 hours
length of stage II of parturition in the dog
6 hours
can be 24 hours
length of stage II of parturition in the cats
first kitten delivered within 60 min
delivered every 30-60min
length of stage III of parturition in the dog/cat
fetal membranes should be passed with fetus or within 15 min
most common cause of dystocia in the canine/feline
Primary uterine inertia
what are the options for medical management? what are the chances for complete success in dogs with medical management of dystocia?
medical management = calcium or oxytocin
28% success rate
Do patients need oxytocin if they are already experiencing uterine contractions?
NO
what criteria make dystocia mild/moderate v. severe?
mild - 4 or less pups remaining
severe - 4 or more pups remaining
normal presentation of the fetus
anterior
normal position of the fetus
dorsal-sacral position
normal posture of the fetus
head and forelimbs extended
cause of primary uterine inertia in cattle
hypocalcemia “milk fever”
what is the difference between an assisted and controlled vaginal delivery
assisted - dam awake, standing or recumbent, sedated or epidural if needed
controlled - anesthesia, no contractions
push fetus cranially out of the maternal pelvic canal into abdominal cavity where more space is available for manipulation is termed what?
repulsion
turning of fetus on long axis is termed what
rotation
rotate fetus perpendicular to its long axis to correct transverse presentation is termed what
version
what is the most common issue/complication with obstetrics intervention
retained placenta
posterior presentation risks
tail head interference
risk of hypoxia due to umbilical cord pinched
transverse presentation risk
no ferguson reflex
main exit vein in the cow?
SQ abdominal v (milk v)
main blood supply to the cow udder?
external pudendal a. & v.
what vessels anastomose to form the milk v with age
cranial and caudal epigastric veins
milk producing cells in the udder
alveolus
what cells surround the alveoli and are stimulated by oxytocin
myoepithelial cells
all mammary tissue is derived from what?
ectoderm
fat pad & median suspensory ligament from mesoderm
what are the main stages of mammary development
band stage
lines
bud stage
components of bovine and equine colostrum
all IgG, most IgM, half of IgA
basic components of bovine milk
water (88%)
lactose
fat
protein
minerals
components of canine colostrum
IgA
what differentiates into teat and gland cisterns during fetal development and growth
primary sprouts
(galactophores)
lactogenesis inhibitory and stimulatory hormones
progesterone - inhibitory
estrogen, prolactin, placental lactogen - stimulatory
hormone that stimulated milk letdown? inhibits milkdown?
oxytocin
epinephrine
how does involution occur
increased hydrostatic pressure
ductal cells resorb
lysosomal enzymes break down & digest epithelial cells decrease
secretion absorbed by lymphatic and venous drainage
stages of involution
active
steady state
redevelopment
colostrogenesis
recommended goal of involution
45 days
causes of galactorrhea in young non-pregnant animas
estrogen (zeralenone)
cystic ovaries
suckling by herdmates/self
genetics
inappropriate milk production by pregnant female prior to parturition?
galactorrhea
causes of agalactia in sow? in horse?
sow mastitis/metritis/agalactia syndrome
ergotism in mares
MOA of ergotism in mares and treatment
Neotyphodium coenophialum = dopamine agonist, inhibits prolactin
Domperidone (dopamine antagonist)
milk letdown failure in cattle due to?
stress - epinephrine
exogenous oxytocin
number one differential for udder asymmetry
mastitis
how to prevent contagious mastitis
post-milk teat dipping
how to prevent environmental mastitis
integrity of teat end
pre-milk teat dip
clean housing
hygienic milk practice
congenital deformaties of the udder
Imperforate plate at gland cistern
Absence of teat cistern
Absence of streak canal
mammary gland development (puberty) requires what hormones
estrogen
progesterone
mammary gland development (pregnancy & lactation) requires what hormones
progesterone
placental lactogen
estrogen
mammary development ceases in most animals after first lactation EXCEPT
cattle and goats (increases up to 4 lactations)
peak milk day
day 90
recommended goal for period of involution
45 days (60 days max)
“drying off”
