Pregnancy toxaemia

What to look for

Cows in late pregnancy become depressed, stop eating and lose weight. After several days, affected cows will go down and, if not successfully treated, will eventually die.

Cause - Nutritional stress

Pregnancy toxaemia occurs when cows in good condition with the high nutritional demands of late pregnancy cannot get enough feed to meet their energy requirements. Under these conditions cow respond by using their fat reserves to provide energy, but in some cases this causes serious metabolic changes and liver damage.

Animals likely to be affected

Cows in the last months of pregnancy that are fat (or in good condition)
Pregnancy toxaemia is usually triggered by a sudden reduction in feed availability or quality.

Other diseases with similar signs

Pregnancy toxaemia is one of a number of metabolic diseases that result from nutritional stress and disruption of the cow’s energy metabolism. Fat cow syndrome and ketosis have similarities to pregnancy toxaemia.

Confirming the diagnosis

Cows with pregnancy toxaemia have a strong smell of ketones (like acetone-based nail polish remover) on their breath. Laboratory tests can provide information on such things as liver function and the level of ketosis.


Pregnancy toxaemia is a veterinary emergency which requires loading the animal with energy sources that can be quickly utilised e.g. injecting large volumes of glucose solutions into the vein. In cases it is necessary to induce calving. Animals in an advanced stage of the disease have a poor chance of recovery.

Risk factors

  • Inclement weather
  • Late pregnant cows that are in very good/fat condition
  • Cows carrying twins
  • Sudden change to a low quality feed or restricted energy intake

Do you want animal health info delivered?

Subscribe to Dairy Australia publications