Large Animal - Pregnancy Problems Flashcards
Define dystocia
Abnormal parturition
Define eustocia
Normal parturition
What do we regard as dystocia when calving?
Any calving that requires intervention
Sometimes not veterinary as farmer can handle a lot of them
What are the four stages around parturition?
Pre-parturient stage
Parturition
Puerperium
Postpartum period
Describe the pre-parturient (prodomal) period
Cow separates off and becomes restless
Udder begins to bag up
Ligament starts slacking off
Important for farmer
When does the farmer notice a problem during the pre-parturient period?
When things are occurring then stop suddenly
What are some examples of problems that can occur during the post-partum period?
Mastitis
NE balance
What are the three stages of parturition?
Stage 1 - foetus positioned for birth, cervix dilated, foetal membranes exposed through vulva, possible rupture of foetal membranes
Stage 2 - Foetus expulsion
Stage 3 - Placenta expulsion
If the cow is making progress what should you not do?
Interfere
What varies between species in regards to parturition?
Duration of the stages of parturition
How long is each stage of parturition in various animals?
Cow - 1 6 hours, 2 0.5 to 4 hours, 3 6 hours
Mare - 1 1 to 4 hours, 2 10 to 30 minutes, 3 1 to 2 hours
Ewe - 1 2 to 6 hours, 2 1 hour, 3 3 hours
Doe - 1 2 to 6 hours, 2 1 hour, 3 3 hours
Sow - 1 2 to 12 hours, 2 4 hours, 3 1 to 4 hours
Bitch - 1 2 to 12 hours, 2 6 hours
Queen - 1 1 to 12 hours, 2 4 hours
What tends to occur in bitches and queens that doesn’t in large animals?
Placenta emerges with foetus
Which breeds have a high incidence of dystocia?
Brachycephalic breeds
Which cows is dystocia incidence higher in?
Beef cattle
What are the three causal categories of dystocia?
Maternal
Foetal
Foeto-maternal disproportion
What are some maternal causes of dystocia?
Expulsion - primary uterine inertia, secondary uterine inertia, defective straining, inadequate straining
Birth canal - failure of cervix, soft tissues or ligaments to relax, uterine torsion, inadequate pelvic diameter
What are some foetal causes of dystocia?
Foetal size - too large, monster
Disposition - abnormal presentation, abnormal position, abnormal posture
What is the main reason for dystocia caused by foetal-maternal disproportion?
Foetal skeleton is too large to fit through pelvis of mother
When is dystocia an emergency?
When the client thinks it is
Severity of emergency always depends on owner
Treat as an emergency whatever
What sort of questions should included in a dystocia history?
Full term, overdue or early? First time or had calves before? Any problems during pregnancy? Number of foetuses? When did straining begin? Hormonal treatments? Water bag, foetal fluids or foetus? Foetus alive?
What should be checked on a general examination of a dystotia cow?
Status of the dam
Exhaustion - struggling to breath, acidotic, straining for too long
Milk fever
What is needed when examining dystocia cows?
Adequte restraint - big animals, ensure she doesn’t pressure you
What is needed for both you and the cow during examination?
Floor grip - prevent slipping
What equipment do you need for a dystocia case?
Parturition gown - stay clean, ideally sterile
Halter
Head and leg snares - rope, chain, lambing aid
Lots of lube - reduce friction
Soap, disinfectant and cotton wool - clean cow off
Syringes
Local anaesthetic - case dependent
Calcium
Antibiotics
Why do we need to be as sterile as possible during a dystocia case?
Dystocia increases chances of endometritis 5 times
Reduce introduction of bugs from us
What four things should you think about during a specific examination of a dystocia case?
Hygiene - vet, dam, environment
Lighting
Assistance
Position of dam - sow lying, cow standing, mare standing, ewe standing
What three things should be examined in the vulva, vagina and cervix?
Injury - check before to ensure you don’t get blamed for it
Dilation of birth canal - calf could struggle to come out
Lubrication
What should you examine the foetus for in a dystocia case?
Three Ps - presentation, posture and position
Number of foetuses
Live or dead - impacts course of action
Size in relation to dam
How can you check whether a calf is alive or dead?
Squeeze on foot and see whether it pulls back
Dystocia can depress reflexes
Feel for heartbeat instead or umbilicus
Eye socket can be a good place to look
What three things shuold be thought about when correcting dystocia by manipulation?
Lubrication
Repostioning
Traction
What are the three methods of correcting dystocia?
Manipulation
Foetotomy - only if calf is dead
Caesarean section - not before trying traction
What are the five types of anaesthesia that can be given to a cow in dystocia to help parturition?
None Epidural Paravertebral Inverted L Line block
Why should you be careful giving cows sedation?
Can go down which will hurt both you and the cow
What three things should be thought of when calving a cow?
Foetal-maternal disproportion
Management of expectations - likelihood of success, complications
How much force can be used - use aids carefully, careful of disproportionate forces compared to cow
How many people should be enough to provide traction force?
One or two
Any more might be a problem
Describe a traction forced extraction
Repostion calf
Ropes or chains on both legs
Manually dilate vagina and vulva
Look for space in pelvis - hand above head, straight legs
Pull downwards
With the carpal joint 10cm outside of the cow - 2 people pulling should fit
Double muscled calf - only one person pulling
Coordinate pulling with straining of the cow - aid calving process
Once head is born rotate 90 degrees and change pulling direction dorsally
How should you rotate a calf to ensure it can fit?
Cross front legs
Pull calf down and to one side
What should be done with a calf presenting caudally?
Manually dilate vulva and vagina
Check umbilical cord
If it fits pull and deliver
Hock joint 10cm outside cow - 2 people pulling should fit
Deliver as soon as possible - umbilicus can snap, cutsoff oxygen supply
Pull dorsally
What does foetal presentation describe?
Relationship between longitudinal axis of foetus and dam
What are the three presentations of the foetus?
Longitudinal anterior - normal
Longitudinal posterior
Transverse
What does the foetal position describe?
Relationship between dorsal surface of foetus and surface of maternal birth canal
What are the three positions a foetus can be in?
Dorsal - normal
Ventral
Lateral
What does foetal posture describe?
Disposition of movable appendages of the foetus
What three posture changes can occur?
Limb flexions
Neck flexions
Head displacements
What are some reasons for incorrect disposition of a foetus?
Weak uterine contractions Delayed development of foetal reflexes Weak foetal movements Competition uterine space Oversized calf Ankylosis of joints
What aftercare should be provided for a dystocia case?
Mother - trauma care, antibiotics, oxytocin, NSAIDs
Neonate - dip navel, colostrum supply
What is the average calving rate in the UK?
43%
When do most embryonic losses occur?
By day 42
When does early embryonic mortality occur?
Before maternal recognition of pregnancy
First return to oestrus
Regular returns
When does late embryonic mortality occur?
After maternal recognition - irregular return
Before completion of organogenesis/foetus
When does foetal loss occur?
After day 42 in the cow
Whyshouldyou scan again 2 or 3 weeks after first scan?
Ensure that no foetal loss is taking place
What are the two broad categories of factors affecting pregnancy rates?
Physiological
Pathological - genetic, environmental
What percent of embryos tend to be genetically abnormal?
10%
How does BCS affect pregnancy rate?
Loss of BCS reduces pregnancy rate
How does dietary protein affect pregnancy rate?
Less protein means more services per conception
What are some infectious agents that can cause loss of pregnancy?
Leptospira hardjo Ureaplasma diversum Campylobacter fetus Bovine herpes virus 1 Bovine virus diarrhoea virus Neospora caninum
How likely is it that an infection caused pregnancy loss?
Not likely
Keep in back of mind though
What is the most likely cause of pus emerging from the vagina?
Endometritis - not good for foetal development
What can cause stress that can affect pregnancy?
Overcrowding
Incorrect housing
Incorrect flooring
How can rectal palpation affect pregnancy?
The more we feel for the higher the chance of foetal loss
What iatrogenic things can affect pregnancy?
Corticosteroids - induce pregnancy
Prostaglandins
Oestrogens - impact on fertility
Oxytocin
What are the four descriptions of foetal loss?
Maceration
Mummification - CL persists, calf doesn’t trigger breakdown
Abortion - one or more calves between 152 and 270 days
Still birth - born dead or survived less than 24 hours
What complications can cause foetal loss?
Hydrops
Uterine torsion
Vaginal prolapse
Uterine prolapse
What is hydrops?
Oedema of placenta
Describe hydrops
Placental oedema
Typicallyin last 3 months of pregnancy
Variable amounts of fluuid
What options are there for a cow with hydrops?
Cull
Induce parturition - corticosteroids, prostaglandins (more effective)
2 stage caesarean - rid of fluids, get calf out
What should always be checked before inducing parturition?
Not carrying twins
Describe hydrops of the foetus
Canhave hydrocephalus, ascites or anasarca
What are the treatment options for foetal hydrops?
Partial foetotomy
Caesarean section
When does uterine torsion tend to occur?
End ofterm in cattle
Around 9 months in the mare - present as colic
Which cows is uterine torsion more common in?
Heifers
What should be done to detect uterine torsion?
Vaginal exam
Rectal exam
What shouldbe done with a uterine torsion?
Reposition using internal or external forces
Remember which way to turn
What animals is cervical vaginal prolapse more common in?
Sheep
Cattle
What are the predisposing factors to vaginal prolapse?
High BCS or low BCS High roughage diets/high rumen fill Twins Increased oestrogens Lack of exercise Urinary retention Breed Age
What are the consequences of vaginal prolapse?
Infection - caudal genital tract, cranial genital tract Debility/inappetance Urinary retention Rupture of dorsal or lateral wall Visceral eventration
Describe treatment of vaginal prolapse
Necessary - painful, loss of mucus plug ofcervix, infection risk
Caudal epidural - local anaesthetic, xylazine
Various methods - harness, surgery
What should be done with uterine prolapse?
Treat immediately - can be hypocalcaemic Emergency! Support prolapse when cow is standing Remove foetal membranes Epidural block Frog position Kepp pushing on back Use sugar Bottle to push further
What is the puerperium period?
Period after parturition when reproductive tract returns to non-pregnant condition
What four normal processes occur during pruerperium?
Involution
Endometrium regeneration
Elimination of contaminants of the reproductive tract
Resumption of cyclical activity
What are four disorders that affect the normal puerperium?
Dystocia
Uterine prolapse
Retention of foetal membranes
Uterine disease
What is involution?
Reduction of uterus and cervix after calving
When does the greatest decrease in uterine size occur?
First few days after calving
When should the whole of the uterus be palpable rectally?
8-10 days post partum
How long does it take for complete involution to occur?
Within 26-50 days
How big should the cervix be 96 hours post partum?
Only 2 fingers should be able to fit in
What shift occurs in involution?
From hypertrophy to atrophy
What may control involution?
Prostaglandins - exogenous use can accelerate involution
Describe endometrial regeneration postpartum
Uterine caruncles undergo degenerative changes - vasoconstriction and ischaemia, results in necrosis and sloughing of tissue
Necrotic material constitutes post partum lochial discharge - occurs 2-9 days post partum, yellowish or reddish brown, volume variable, not a fetid odour
Systemic response observed
Caruncular and inter-caruncular surfaces - covered with endometrial epithelium
What bacterial species can contaminate from the uterine lumen?
Arcanobacterium pyogenes E. coli Streptococci Staphylococci Fusobacterium necrophorum
What is the main mechanism for bacterial elimination?
Phagocytosis by migrating leucocytes
Physical expulsion by uterine contractions and secretion
How does the normal ovarian cyclical activity resume after birthing?
Increase in plasma FSH 7-10 days post partum
Ovulation occurs if follicle produces enough oestradiol to stimulate adequate LH secretion
Luteal phase may be normal or shortened
Why does dystocia affect normal puerperium?
Breaks host defence mechanisms
What three things does dystocia cause that affects normal puerperium?
Physical deformity of the vulva and cervix
Tissue damage so more prone to contamination
Uterine inertia
What does dystocia predispose an animal to?
Retained foetal membranes
Uterine disease
Which cows is uterine prolapse more common in?
Pluriparous cows
Ones that are grossly protracted
Had assisted parturitions
When does uterine prolapse usually occur?
24 hours post calving
What are the risk factors associated with uterine prolapse?
Prolonged dystocia Foetal traction Foetal oversize Extreme laxity of the perineum and vulva Hypocalcaemia Paresis Retained foetal membranes
Describe treatment of uterine prolapse
Protect and support the prolapse Calcium borogluconate Relieve ruminal tympany Restrain the cow Epidural Clean the uterus "Frog-leg" position Gentle replacement Insure total inversion Stitch the vulva Antibiotics and NSAIDs Oxytocin
What is the incidence rate of retained foetal membranes?
6-8%
25-40% with dystocia
Describe separation and expulsion of the placenta
Placenta matures
Changes in progesterone and oestrogen concentrations
Changes in collagenase and proteases/glucosaminidases
Number ofbinucleated cells in the trophectoderm is reduced
Foetal side of the placenta is exsanguinated
Trophectodermal villi collapse
Placentome distortion
Lack of antioxidants, stress, oxidative injury and role of PGF and PGE synthesis
IL8, leukocyte migration and collagenases
Leads to separation and expulsion of placenta
What are the reasons for retained foetal membranes?
Failure of placental maturation
Failure of detachment of foetal and maternal villi of the placentome
Inadequate uterine contractions due to hypocalcaemia or dystocia
What are the predisposing factors for retained foetal membranes?
Abortion Stillbirth Multiple birth Dystocia/premature calving Infectious placentitis Hypocalcaemia Hydrallantois Increasing age of the dam Prolonged gestation Micronutrient deficiencies
What are the clinical features of retained foetal membranes?
Morbidity - lackof appetite, reduced milk yield
Mortality - 1-4% mainly related to metritis/toxaemia
Fertility - no effect on its own if mating 60 days post-calving, with metirits increases days open, services per conception, calving to first oestrus/service interval
What does the duration of retention of foetal membranes depend on?
Myometrial contractions
Describe the treatment for retained foetal membranes
Treat for metritis - pyrexic, decreased appetite, decreased milk yield
Parenteral or intrauterine antibiotics
Prostaglandins/oxytocin
Collagenase infusion into umbilical artery stumps
What are the three types of uterine disease?
Endometritis
Metritis
Pyometra
Describe endometritis
Disease of endometrium and stratum spongiosum of submucosa
No systemic illness
Leukocytes but no pus in uterine discharge
Describe metritis
Disease of deeper layers of uterus
Systemic illness - mild to very severe
Describe pyometra
Chronic
Purulent exudates
Corpus luteum
No systemic signs
What does uterine disease usually impair?
Fertility
What two ways does infection develop in the uterus?
Breaking physical barriers of vulva and cervix - dystocia/RFM increases load of pathogens, causes tissue damage and deformity, uterine inertia
Comprimising immune defence system
What two things does bacterial load depend upon?
Level of contamination
Species of bacteria
What are the clinical signs of endometritis?
Mucopurulent discharge in clinical cases
No systemic illness
Neutrophils in uterine luminal fluid
How is endometritis diagnosed?
Rectal palpation - poorly involuted uterus
Presence of discharge around cervicalos
Metricheck to collect discharge
Describe endometritis treatment
Stimulation of oestrus in both cyclic (PGF2alpha) and acyclic (E2, GnRH) cows
Intrauterine cephapirin - metricure, intervet
What are the clinical signs of metritis?
Systemic illness
Purulent fetid fluid in uterine lumen
Distended, fluid-filled atonic uterus
Elevated rectal temperature (40-41 degrees C)
Dullness, depression, milk drop,inappetance
Severe dystocia, uterine inertia or RFM
Sore, swollen and inflamed vagina and vulva
Systemic toxaemia
Pyaemia
What is the treatment for metritis?
Case dependent Supportive therapy Parenteral antibiotics Oestrogens increase absorption of endotoxins Uterine lavage followed by antibiotics
What arethe clinical signs for pyometra?
Accumulation of purulent material in the uterus Presence of active persistent CL Large distended uterine horns Closed cervix Follows chronic endometritis No signs of ill health Cyclicity absent
What is the treatment for pyometra?
PGF2alpha
Intrauterine cephapirin
What are the signs of impeding parturition in cows, sheep and does?
Slackening of pelvic ligaments Change in mammary secretion to colostrums Fall in temperature Signs of abdominal pain Occasional straining Irregular rumination Belly kicking May stand with back arched and tail raised Go down and rise again frequently
What are the signs of impeding parturition in pigs?
Swelling of vulva 4 days prior Mammary growth 1-2 days prior Milk expressed 24 hours prior Mostly asleep in lateral recumbency Marked restlessness and nest-making Intensely active period followed by recumbency and rest Intermittent clawing and champing of bedding Periods of alternate activity and rest
What are the signs of the second stage of parturition in cows, sheep and does
More frequent straining
Initially remains standing
Lays down during passage of head through vulva
Remains recumbent until baby is born
What are the signs of the second stage of parturition in pigs?
Cannot distinguish second and third stage
Usually remain recumbent
Intermittent straning with leg paddling
Foetal fluid will be passed with tail twitching before each birth
Most effort made to expel first piglet
