Dystocia Flashcards
What is the most common cause of dystocia in cattle and sheep?
cattle - feto-maternal disproportion
sheep - malpresentations
What are the effects of dystocia?
- Reduced welfare
- Reduced production
- Cow = subsequent lactation
- Calf = 1st lactation
- Stillbirth
- Dam death
- Postpartum problems
- E.g. RFM, metritis, injuries
What are the options for management of dystocia?
- Manual correction and deliver per vaginum
- Caesarean section
- Foetotomy (foetus needs to be dead)
- Euthanasia of dam +/- foetus
When is manual correction and delivery successful?
If foeto-maternal disproportion NOT present
- Malpresentations
- Some soft tissue obstructions (e.g. vulval stenosis)
What are the indications for a caesarean section? When is it not suitable?
- foeto-maternal disproportion
- malpresentations that cannot be corrected
- breech calves
- elective (e.g. high value calves)
Not suitable if calf decomposing -> foetotomy
- Alternative approach needed if C-sec performed
What are the advantages and disadvantages of a C sec?
Advantages
* Increased chances of live birth
* Reduced risk of secondary complications such as nerve injury
* Can be quicker and less injurious to dam than prolonged difficult calving/lambing/kidding
* Survival rates for dam and offspring are favourable
* Can be quicker than a difficult per vaginum delivery
* The only method to deliver an oversized foetus intact
Disadvantages
* Inherent surgical and anaesthetic risks apply (as to all surgeries)
* But… may be increased risk of secondary infection (e.g. peritonitis) or adhesions
* Requires veterinary qualification and surgical competency
* Can be physically demanding in cattle, especially if the calf is large
What are the indications for foetotomy? What is the difference between partial and total foetotomies?
Indications Foetus is already dead
* Foeto-maternal disproportion
* Pathological foetal oversize
* Congenital foetal malformations
* Malpresentations that cannot be corrected
Partial = removal of part of the foetus only (e.g. head)
Total = division of the whole foetus into two or more sections
What are the advantages and disadvantages of foetotomies?
Advantages
* Reduction in foetal size allows easier delivery
* Can be quick (especially partial)
* Can be done without assistance (although assistance recommended if possible)
* Avoids C-sec
* Especially useful if C-sec contraindicated (emphysematous foetus)
* Better for dam in some circumstances
* Can be performed with minimal equipment if required
* Especially sheep
* Partial needs less equipment
Disadvantages
* Risk of iatrogenic injury
* Can be severe or even life-threatening
* Can take a long time (especially total)
* Exhaustion of dam and vet
* Requires training and technical competency
What are dropsical conditions? What are the 2 types?
‘Dropsy’ = accumulation of fluid
Hydrallantois
* Excess fluid accumulation in the allantois
* 85-90% of bovine cases
* Placental origin
* Foetus normal
* Sporadic occurrence
* Up to 10x expected volume of allantoic fluid
* Normal = 8-15 L
* Fluid accumulates after mid-gestation
* Failure in mechanisms of production and absorption
* Reduced number of placentomes
* Permanent alteration of endometrium
* Prognosis guarded to poor
* If survives, cull of cow recommended
Hydramnion
* Excess fluid accumulation in the amnion
* ~10% of bovine cases
* Foetal origin
* Foetal abnormalities present
* Related to foetal abnormalities
* Failure of swallowing or digestion of foetal fluids
* Future breeding prognosis of dam is reasonable
* Progressive abdominal enlargement in 3rd trimester
* Slower development than hydrallantois
* Uterus and abdomen accommodates extra fluid better
* Less sick cow
* Placentomes still palpable
* May go undiagnosed until parturition
* Large volume of thick, syrupy fluid
* Foetal abnormalities
Occasionally both occur together
What clinical signs are associated with hydroallantois?
- Bilateral abdominal distention
- Symmetrical
- Uncomfortable
- Inappetant
- Reduced/absent rumen function
- Due to compression
- Recumbency
- Tight uterine wall palpable per rectum
How would you treat hydroamnion/hydroallantois?
Induce/terminate pregnancy
* Prostaglandin / steroids
* Need to provide replacement fluids to cow
* Prevent hypovolaemia
* Correct electrolyte disturbances
Euthanasia
- Salvage slaughter if fit to travel
Trochar and drain fluid
* Rapidly re-accumulation of fluid occurs in hydrallantois
* Need to provide replacement fluids to cow
What is arthrogryposis? What are causes?
- Relatively common malformation
- Limb ankylosis
- Usually combined with other congenital malformations (e.g. cleft palate)
- Liveborn neonates unable to stand -> euthanasia
- Foetotomy or C-sec usually needed
Causes
* Genetic
* Autosomasal recessive in Charolais breed
* Viral infection in utero
* Schmallenberg virus
* Bluetongue virus
* Akabane virus
* Teratogenic plants
* Lupines (not all species)
What is schistosomus reflexus?
- Inside out’ foetuses
- Rare, fatal malformation
- Likely genetic
- Foetotomy or C-sec
- Be careful not to confuse with uterine rupture
What is congenital chondrodysplasia?
- ‘Bulldog’ calves
- Short legs
- Domed head
- Brachygnathia inferior (undershot jaw)
- Dexters, Holstein, Jerseys
- Likely genetic
- Other breeds reported
- Does not always = dystocia
What is hydrocephalus?
- Increase in CSF volume -> domed head
- Calves born alive may have neuro deficits
- Teratogenic viruses implicated
- BVDv
- BTV
- Akabane virus (not UK)
- May also form part of mixed congenital disorders
- Mild cases may calve unassisted
- Severe cases = C-sec
What are possible cranial defects?
- Ancephaly – no head (images 1a and 1b)
- Otocephaly – some head structures present but no skull (image 2)
- Bicephaly – two heads (image 3)
