Reducing Risk of Displaced Abomasum (DA)

October 7, 2020

Often referred to as a ‘twist’, a displaced abomasum (DA) is an expensive event on the farm.  Associated costs include:

  1. Loss of milk production – 700-1200lb less milk produced in the lactation
  2. Veterinary costs – surgery, medicine
  3. Replacement costs – due to increased risk of culling or death

What causes a DA?

DAs is a multifactorial disorder, at times with a complex web of contributing factors – some of which I have listed below. I find it helps to think about risk factors and associated management practices within the following formula:

↑Space in Abdomen + Motility & ↑ Gas in Abomasum = ↑ Risk of DA

Risk factors associated with an increase in abdominal space 

  • Deeper barrel conformation of modern cows
  • Calving (i.e. loss of calf weight, placenta, and fluids)
  • Reduced dry matter intake and rumen fill
    • Calving time (i.e. natural drop in dry matter intake)
    • Concurrent disease-causing inappetence, e.g. metritis, mastitis, pneumonia…
    • Ration issue, e.g. wet silage, palatability, high energy/low fibre, mixing errors
    • Bunk issue, e.g. competition, infrequent push-ups, limit feeding
    • Cow comfort, e.g. stall design, ventilation, heat abatement
    • Social stress, e.g. pen movements in the transition period

Risk factors associated with low abomasum motility and excessive gas accumulation

  • Hypocalcemia (i.e. calcium required for contraction of all muscle types), e.g. dry cow nutrition, parity (lactation #), genetic predisposition
  • High rumen volatile fatty acids (VFAs), e.g. high energy/low fiber ration, sorting
  • Ketosis (low glucose and insulin lead to reduced abomasum motility), e.g. over-conditioned cows at freshening (body condition score >4), dry cow nutrition

How do I reduce the risk of a DA in my herd? 

It is not realistic to expect the elimination of DAs, but rather a target of <4% annually is achievable. Review your farm protocols and engage your vet and nutritionist farm advisors on the following subjects:

  • Monitoring, preventing and treating fresh cow illnesses
  • Nutrition management
      • Ration formulation for optimal dry matter intake and suitable fibre/energy levels
      • Critical control points for delivery of a consistent and appropriately processed ration
  • Regular dry matter testing
    • Ensuring feed changes are gradual and are preceded by forage testing and ration formulation

Facility and cow comfort strengths and opportunities – e.g. stall design, social groupings, bunk competition

Dr. Shannon Walsh

If you have any questions on these or other topics, please do not hesitate to contact one of our Veterinarians.

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