Normal Parturition + post-partum period Flashcards
Describe the stage of preparation of parturition
Placenta releases hormones, influencing the fetal hypothalamus.
Fetal stress signals (hypoxia, blood glucose changes, etc.) activate the hypothalamus.
The hypothalamus stimulates the pituitary, which releases ACTH.
ACTH triggers the fetal adrenal glands to produce adrenaline and corticosteroids.
These hormones promote fetal maturation, preparing for birth.
This cascade initiates labor by signaling maternal hormonal changes.
also the effect of late term relaxin production => relaxing and softening of cervix pelvic ligaments and perineum
Describe first stage parturition
Describe 2nd stage parturition
Describe 3rd stage parturition
Abdominal contractions largely cease
Myometrial contractions decrease in amplitude, increase in frequency and become less regular
Baseline uterine tone increases
Placenta expelled
How long does parturition last in different species?
Mare 30 minutes
Cow 1 hour
Ewe 1 hour
Queen 2 hours
Sow 3 hours
Bitch 6 hours
What are the maternal causes of dystocia?
Inadequate expulsive forces:
- uterine inertia
- weak abdominal straining
Inadequate size of birth canal:
- incomplete dilation or constriction of birth canal
- inadequate pelvis
What are the foetal causes of dystocia?
Oversized:
- relative and absolute e.g., small litter, prolonged gestation
- congenital monsters
- foetal pathology e.g., ascites, emphysema
Fault disposition:
- presentation
- position
- posture
Describe primary and secondary secondary inertia
Give examples of post-partum conditions
Haemorrhage
Trauma/lacerations/contusions
Prolapse of something
Placental retention
Metritis
Recumbency / nerve damage
What are the possible causes of post-partum haemorrhage?
Profuse bleeding can be due to:
- Breakage of the umbilicus and blood leaking from the placenta
- Uterine or vaginal laceration
Minor seepage can occur from where placenta attached
Describe trauma/lacerations/contusions seen post-partum
Result of bruising of the wall of the vestibule or vulva during delivery
Perineal laceration: most commonly seen in cow and mare, often at first parturition, and most commonly when there has been forced traction
First degree - Skin and mucosa (usually of dorsal commissure)
Second degree - Deeper laceration involving muscle of perineal body
Third degree - Torn vagina and rectal wall (creating a cloaca)
Vaginal-rectal fistula - Penetration from the vaginal cavity into the rectum but not continuous distally
Describe post-partum bladder protrusion/prolapse
In some cases (ewe or cow) the bladder prolapses through a tear in the vagina (external [serosal] surface of the bladder is visible)
In other cases (mare) the bladder everts through the large urethra (internal [mucosal] surface of the bladder is visible)
Describe uterine prolapse post-partum in different species
Cow and ewe
- Common post-partum
- Usually complete eversion of previously pregnant horn
Sow
- Infrequent
- Eversion of one horn
Mare
- Rare
- Eversion of the whole of the uterus
Bitch and Queen
- Rare
- Eversion of one horn
What causes uterine prolapse post partum?
Associated with uterine inertia or poor involution of a portion of uterus which predisposes to protrusion when there is protracted abdominal straining
May be associated with traction of retained placenta (mare)
Hypocalcaemia is predisposing factor
Describe the treatment of a prolapsed uterus
Epidural, establish ‘frog-leg’ position in cow
Push components close to vulval lips first and gradually replace
Ensure complete inversion
Post replacement: oxytocin, calcium, parenteral antibiotic, NSAIDs
Prognosis: good if treated soon after prolapse occurred
What is the consequence of retained foetal membranes?
Cow - (common post-partum condition) Important in metritis-endometritis-pyometra complex
Mare - metritis -> laminitis (can be very severe)
Ewe, bitch, queen - metritis
What causes retained foetal membranes in cows and mares?
Failure of normal process of dehiscence and expulsion of placenta - not usually due to poor contractions
Cow
- Associated with abortion, dystocia, inertia, hypocalcaemia, caesarean, twins, some mineral/vitamin deficiencies
Mare
- Associated with breed, dystocia, uterine inertia, hypocalcaemia
Describe the treatment of retained foetal membranes in cows
Gentle removal (triple glove!!)
Parenteral antibiotics if clinically ill
Ecbolic have little (PG) or no (oxytocin) effect
Describe the treatment of retained foetal membranes in mares
Treatment is urgent
Can be removed by careful traction
Sometimes ecbolic agents used (oxytocin in different regimes) to increase contractions
Remember careful examination of membranes (fragments remaining = metritis)
NSAIDs and systemic antibiotics
Describe the treatment of retained foetal membranes of bitches and queens
The condition is less common than the concern about it
- Dams often eat the placentae and this is not noted by the owner
- Persistence of green-coloured discharge is suitable confirmation
Diagnosis/treatment is often undertaken from day 2
Ecbolic agents; oxytocin, prostaglandin, ergometrine
Critical other treatments: NSAIDs, parenteral antibiotic, fluid therapy
Describe post-partum metritis
Associated with dystocia, assisted parturition, placental retention
Placenta detaches and pulls some of the uterine surface with it leaving deeper tissue layers exposed to bacteria and infection
Affects most species:
- May be severe and be associated with odorous discharge and acute toxaemia with dehydration, pyrexia and collapse
- May be chronic and be mainly a pooling of fluid in the uterus
Describe the treatment of post-partum metritis
Fluid therapy, NSAIDs, intra-uterine and/or parenteral antibiotics, drainage of fluids by oxytocin or PG administration (remember no CL), calcium administration, uterine lavage
Describe post-partum recumbency/nerve damage in cows
Most common in cows due to nerve damage during parturition
Gluteal paralysis
Obturator paralysis
Treatment with NSAIDs, hobbling, and provision of firm footing
General nursing and attention to mammary glands is important
What is post-partum recumbency in mares commonly associated with?
colic
general weakness/age
cast
