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Bovine dystocia - Coggle Diagram

- - - - ET tube
    - - artificial ventilation or resuscitation bag/mask
    - - +acid base status
        
        metabolic acidosis if the calf cannot achieve sternal recumbency within 3 mins of birth
        
        if calf breathing or being ventilated can administer sodium bicarbonate slowly IV to correct acidosis
    - - Brachial plexus injury in the foreleg (radial, ulnar and musculocutaneous nerves) occurs very occasionally in the neonate during excessive traction of a large calf in anterior presentation.
        
        Splinting the distal limb to prevent contracted flexor tendons (can lead to pressure sores)
        
        During excessive traction of a large calf in normal forward presentation when the cow lies down with the calf halfway out.
      - Femoral nerve injury is most common after a calf in anterior presentation becomes hip-locked when excessive traction is used to aid delivery. Injury results in the inability to extend the stifle joint, bear weight and extend the affected leg(s). There is rapid atrophy of the Quadriceps femoris muscle group within seven to 10 days. Calves with bilateral femoral paralysis are unable to stand and adopt a dog-sitting posture. Calves with a unilateral lesion have difficulty rising to their feet and are unable to fix the stifle joint and the pelvis is markedly tilted toward the affected side.
        
        recovery from severe cases can take 9-12 months
        
        Prognosis is related to the severity of the clinical signs but it can take up to a year for the calf to recover resulting in decreased growth rates. Femoral nerve damage can result in lateral patellar luxation due to atrophy of the quadriceps and, although the patella can be replaced easily, the animal has extreme difficulty walking.
      - fracture of a femur in a calf carries a hopeless prognosis and the calf should be euthanised for welfare reasons, cannot cast or confine to calving box
  - - - usually result of insufficient vaginal dilation or lack of librication
      - often left to heal without suturing, may need antibiotics
      - Tears in the vaginal wall during delivery of the calf may be sufficient to allow the protrusion of submucosal fat or extend to cause rupture of the uterine artery with life-threatening consequences.
    - - may occur immediately or a few hours after parturition
      - associated with foetal oversize and hypocalcaemia
      - possible complications of uterine prolapse
        
        rupture of uterine blood vessels
        
        may bleed internally to death e.g. broad ligament
        
        Blood clots
        
        may form in the stretched uterine vessels which are released when the organ is replaced
        
        outcome depends on size of clot and where it finally lodges
        
        hypothermia
        
        massive amounts of heat can be lost from unprotected surface of a prolapsed uterus - esp. if lying on cold wet ground
        
        environmental contamination
        
        Trauma
        
        infection - metritis and endometritis
  - - - will likely heal on own (difficult to suture) may lead to fibrosis and future difficulties
    - - euthanasia may be only option
    - - clean towels/sheets to limit bleeding, uterine involution may also help
    - - may be sutured but may form strictures when healed
    - - TLC vital
      - prognosis varied
      - sciatic > obturator > peroneal
      - Hip-lock during anterior presentation of the calf is the most common cause of adductor paresis (obturator nerve and sciatic nerve injuries) in the cow.
      - Prevention of obturator nerve paralysis is simple - avoid prolonged second stage labour and/or excessive traction during calf delivery.
      - Peroneal nerve paraylsis results in flexion of the hock and the dorsal surface of the hoof may contact the ground, and is typically seen affecting one hind foot after a period of recumbency.
      - obturator nerve damage (splits)
        
        The hobbles need to be placed on the pelvic limbs just above the fetlock joints with wide webbing no more than 45 cm apart. Bailer twine is rough and will result in trauma to the skin so should never be used for hobbles, wide webbing will support the legs and be gentle to the skin. They need to be fitted above the fetlocks so the cow can get up and down easily and the length of the webbing has to allow the cow to stand and walk without causing further trauma or stress to herself.
    - - calcium borogluconate IV or SC
      - phosphorus and magnesium supplements may help
    - - repeat infertile cows should have history considered for recent signs of dystocia, may lead to increased culling rate
- - - - corneal reflex
      - tongue/limb retraction
      - palpation of heart beat
      - palpation of umbilical pulse
      - general calf movement
      - anal tone if posterior presentation
      - caution for abdominal contraction of dam or movement of the calf in the atonal stages
  - - - The calf's forequarters are removed and the remaining vertebral column and pelvis are divided using embryotomy wire. The split hindquarters can be pushed apart and easily removed
        
        further traction at this stage can lead to obturator/sciatic nerve damage of cow (splits)
- - - - release of prostaglandin F2alpha from endometrium leading to luteolysis
  - - - uterine contractions begin
      - calf rotates on long axis
      - dam exhibits behavioural changes and cervix softens
        
        restless
        
        separate from herd
      - factors which stop or delay calving at this stage
        
        stress
        
        via the effects of adrenaline/noradrenaline
        
        exogenous clenbuterol
        
        beta agonist which causes smooth muscle relaxation
        
        relaxes uterus and causes cessation of uterine contractions
        
        this can be used along with the pumping action of fluids into the uterus to make space for manipulation of the foetus
        
        must follow with a dose of oxytocin (once task completed) to aid in contraction and prevent likelihood of a uterine prolapse occurring
    - - calf delivered via uterine and abdominal contractions
      - 30 mins - 4 hours (average 70min)
        
        longer in heifers than cows
      - when to assist
        
        30-60min in cow
        
        60-90 min in heifers
        
        water sac visible for 2h but cow not trying or cow has been straining for over 30 min and not making progress or stopped trying for 15-20 mins after a period of progress.
      - cow will be lying down to push harder (if stand her up she will not apply too much force in pushing)
    - - neonate stimulated to breathe by build up of co2
        
        hypercapnia/respiratory acidosis
      - best prognosis for life: sits in sternal recumbency within 5 minutes of delivery
      - takes a few hours
- - - - voluntary ingestion of colostrum reduced
- - - - head needs to stay in birth canal and your hand must fit over the top
      - crossed over calf legs indicates its shoulders are too wide
      - fetlocks cannot come out stop pulling
    - - malformations
        
        schistosomes refluxes
        
        schmallenberg
        
        bulldog calf
    - - gyn sticks or roll cow (Rueff's method)