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Physical changes predicting pregnancy

-relaxation of pelvic ligaments
-poor tail tone
-filling of udder
-filling of teats, milk vein engorgement
-drop in body temp
-behavioral changes (mare off feed, bitch more friendly)

280 days

Cow gestation period

341 days +/- 2-3 wks

mare gestation period
-those foaling in jan-march have ~10 day longer gestation

63 days +/-1 day

-bitch gestation period

progesterone drop

-in cow, P4 <1ng/ml is 99% accurate in predicting parturition in next 12hrs
-expensive, not practical
-in bitch, shown by drop in rectal temp 1-2 degrees C
-in mare occurs ~1hr before parturition

Foaling predictors

-best to use all signs together
-due date
-udder development
-pelvic ligaments
-milk composition

Stages of labour

stage 1) uterine contractions, repositioning of fetus, dilation of cervix
stage 2) rupture of chorioallantois & delivery of foal
stage 3) passage of placenta (happens w/ puppies in bitch)

Signs of stage 1

cow: anorexia, arched back, restless, elevated tail
mare: anorexia, colicky, patchy sweating, frequent urination/defecation
bitch: panting, vomiting, nesting, restless

Fetal positioning in late gestation in mare

-by about 8 months hindfeet become trapped by limb horn
-holds fetus in this position until term
-need to roll over & extend front feet & head when they are born

Stage 2 labour in mare

-begins with breaking of water
-rupture of chorioallantois occurs at cervical star
-delivery of foal takes 5-30 min
-want foal to come out in lateral recumbancy

Stage 3 labour in mare

-delivery of placenta
-should occur w/in 3 hrs of delivery or is considered retained in mare
-important to evaluate placenta for intactness & problems

Red bag delivery

-absolute emergency
-premature separation of chorion from uterus
-hypoxemia of foal
-break membrane & deliver foal immediately

When help is needed

-failure of delivery to progress as expected is cause for alarm
-absence of correct presentation of head & limbs
-nose or foot coming out of mare's rectum
-mare straining for more than 20 minutes w/ no progress

Maternal causes of dystocia

-abnormalities of pelvis (fractures), cervix (ringwomb), vagina
-uterine torsion
-uterine inertia (no contractions)


-occurs in sheep
-cause unknown
-genetic link, runs in certain bloodlines
-normal hormonal changes don't happen, no signs of impending labour
-presents as fetal membranes hanging from vulva
-tx-usually c-section

Uterine torsion

-direction v. important!
-correct first, rolling & detorsion
-C-section usually req'd

Fetal causes of dystocia

-fetal maternal disproportion
-fetal misalignment, presentation, posture or position
-multiple fetuses
-fetal monsters

Fetal maternal disproportion

-most common cause of dystocia in cattle
-rare in other species

Fetal misalignment

-most common cause of dystocia in horses
-incl abnormalities of presentation, posture or position

Presentation of fetal alignment

-describes relative assoc of long axis of fetus w/ maternal birth canal
-which half of fetus is presented first at entry to birth canal
-normal is anterior (joints flex in same direction) longitudinal & posterior (joints flex in opposite direction) longitudinal

Position of fetal alignment

-describes surface of maternal birth canal to which the dorsal part of fetus is aligned
-dorsal-sacral is normal

Posture of fetal alignment

-describes disposition of fetal head, neck & limbs
-normal is extended head & limbs


-posterior w/ bilateral hip flexion
-have butt & head

Abnormal presentation

-transverse: fetus lies in pelvic inlet
-dorsal: fetal back at pelvic inlet
-ventral:all 4 limbs at pelvic inlet
vertical:fetus sits vertically in pelvic inlet, 'dog-sitting'

Obstetrical principles

-care & caution
-rule of 3: must have 3 parts to pull
-have a plan & timelines

Assessing fetal viability

-fetal reflexes (interdigital claw, swallowing, eyeball, anal reflex not consistent)
-heart beat (umbilical, tail, thorax)

Principles in fetal repositioning

-control of limbs/head
-rotation (distal limbs brought medially, joint rotated laterally)
-3 parts in pelvic canal

Assisted vaginal delivery

-performed while cow is standing
-deliver fetus in downward arc
-walk fetus through birth canal one forelimb in front of other

Options for resolution of dystocia

-assisted vaginal delivery
-controlled vaginal delivery (anesthetized)


-dismemberment of fetus to facilitate delivery
-goal is to reduce size of fetus &/or remove offending parts
-complete or partial (preferred in mare)


-instruments used to perform fetotomies
-double-barreled is preferred

Complete fetotomy

-used in anterior presentation, involves 6 cuts
-preferable if worried about contaminating mare in c-section & $$

Partial fetotomy

-strategic removal of offending fetal parts
-ventroflexion of head & neck

Fetotomy aftercare

-retained fetal membranes very common
-thorough exam (trauma, tears)
-uterine lavage
-systemic antibiotics
-supportive care
-gentle exercise

Complications of dystocia

-perineal lacerations
-cervical & vaginal tears
-necrotizing vaginitis

post-partum exam

-freq requested by owner
-anytime a problem is suspected
-usually w/in 24hrs of birth
-incl history, visual inspection, physical exam & repro exam

Visual inspection

-retained placenta
-uterine prolapse
-vaginal discharge
-perineal laceration

Vaginoscopy & vaginal examination

-always check for another fetus
-vaginal tears or bruising
-cervical tears
-assessment of retained placenta

Uterine involution

-mare & cow return to pregravid size by 25-32 days post-partum
-dairy cows start cycling 25 days pp
-cow endometrium is repaired by ~45 days pp

Signs of uterine involution in cow

-check at 3rd wk pp
1) uterus in pelvic cavity
2) diameter of cervix <5cm
3) symmetry of both uterine horns

Mare postpartum period

-foat heat (will foal 1 month earlier next year)
-avg 10 days pp
-timing of next estrus will be "30 day heat"
-rapid uterine involution 32 days
-repair of luminal epi by 4-7 days
-resorption of microcaruncles by 7 days
-normal histo by 14-15 days

Uterine prolapse

-common in cows, rare in mares
-usually immediately postpartum
-contributing factors incl dystocia, forced extraction, fetotomy, hypocalcemia, uterine inertia, thin, malnourished cow

Replacement of uterine prolapse

-cow standing
-give epidural
-wash uterus, remove placenta, evaluate for tears
-+/- give oxytocin
-replace uterus by gently alternating dorsal & ventral parts
-infuse fluid & give oxytocin
-Buhner suture

Uterine prolapse prognosis

-good for uncomplicated cases
-potential for hemorrhage from uterine vessels

Retained fetal membranes -cows

-results from anything that interferes w/ normal maturation, flattening, uterine contractions & expulsion
-if sick give systemic antibiotics
-intrauterine antibiotics
-manual removal
-evacuation of uterus (lavage)

Retained fetal membranes in mare

-retained if not passed w/in 3 hours
-potential for serious consequences in mares (toxic metritis, endotoxemia, laminitis)
-treat as emergency
Tx: low dose oxytocin, uterine lavage, systemic antibiotics or fluids if needed

Burns technique

-used to remove RFM from mare
-keeps vagina/uterus from prolapsing
-distend intact chorioallantois w/ fluid for 20-30min
-stretches membrane & uterus

Uterine artery rupture

-causes hematoma formation in broad ligament
Tx-keep quiet, supportive care, monitor PCV & mm colour
-usually live if hemorrhage is limited to broad ligament

Cystic ovarian disease

-major cause of reproductive inefficiency in cattle
-occurs in 12-14% of all problem breeder cows
-follicular-like structures >2.5cm
-persist >10 days in absence of CL
-before 50 days postpartum, 50% of COD cases resolve spontaneously
-examine all cows 45 days pp


-inflammation of endometrium, not sick


-inflammation of uterus

Septic metritis

-early postpartum
-toxic infection
-acute, severe illness

Follicular cysts

-pathological cysts
-Tx: pgf2 alpha
-thin walled, fluid-filled
-follicle continues to grow but fails to ovulate
-not cycling so have low serum P4
-usually multiple

Luteal cysts

-pathological cysts
-Tx: spontaneous recovery, GnRH/pCG or CIDR
-thick wall, usually single
-wall of cyst may luteinize & prod progesterone
-moderate to high P4

Puerperal period

-calving to GnRH responsiveness
-day 7-14 pp
-uterine involution & bacterial clearance
-metritis, septic metritis, endometritis

Intermediate period

-to first ovulation, d21 (mare =10)
-continues involution & bacterial clearance
-endometritis, pyogenes + gram neg anaerobe

Postovulatory period

-to complete involution
-d45 & after
-endometritis & pyometra


-aka metricure
-labelled in cows for intrauterine tx of subacute & chronic endometritis
-single tx
-active in pus & debris & anaerobic environment


-most effective in post-ovulatory period against A. pyogenes
-least effective in early period due to penicillinase-producing organisms


-most effective in early period, works in anaerobic conditions & in presence of pus
-irritating used intrauterine, can cause sloughing of endometrium
-better used systemically for metritis w/ sick cow


-clinical signs incl large fluid-filled uterus
-cows are not sick
-CL present!
-cause damage to endometrium , inability to prod PGF2a, no luteolysis
-WBCs in pus prod PGE that keep CL around
Tx: PGF2a, +/-lavage or intrauterine antibiotics

Cystic corpora lutea

-normal functioning CL w/ fluid filled center
-found in up to 1/3 of CLs in mares in early diestrus

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