Down cows - low phosphorous

dairy cows

There are several different reasons for a cow to be down. This can range from metabolic (milk fever, low magnesium, ketosis, acidosis), to an injury e.g. dislocated hip, or nerve damage from bulling injuries. Other issues can include mastitis, metritis (infection of the uterus), or calving paralysis.

Why could it be low phosphorus?

  • Most commonly occurs around calving in conjunction with milk fever
  • Any animal that is off her feed e.g. sick
  • High yielding, older cows
  • On a diet low in phosphorus pre-calving e.g. fodder beet.

What are the signs of low phosphorus?

  • ‘Down cow’ that doesn’t respond to milk fever treatment
  • ‘Crawler cow’
  • Anorexia, muscle weakness
  • Red water/bloody urine.

How do we diagnose this?

  • Unresponsive to milk fever treatment (calcium)
  • Blood test.


  • MOST low phosphorus cows will spontaneously recover when treated for milk fever
    • Normal gut function is restored so the cow can hew cud & adsorb phosphorus
    • Treatment for milk fever
      •  A bag of calpromag/mixed bag one in the vein and one under the skin
      • Oral drench with starter plus/calol/ketoaid
      • Metacam/ketomax for anti-inflammatory.

What else to give if an animal isn’t responding:

  • Oral drench of DCP (di-cal-phos)
  • OR seek veterinary assistance for injectable treatments.