Ketosis (Acetonaemia) in cattle

Livestock disease investigation case report

Plant toxicity was initially suspected as the cause of cattle deaths on a pastoral property north of Alice Springs. Necroscopy on an eight-year old Brahman cross cow revealed the animal was in reasonable body condition and approximately seven months pregnant with a grossly pale and friable liver. Ketosis was confirmed through testing of blood samples collected. Ketosis occurs in cattle when the animal uses more glucose (sugars) than what it is able to acquire from available feed. Excessive ketone bodies in the bloodstream come from the breakdown of fat when the animal is forced to draw on its bodily reserves for energy. Although the metabolism of body fat provides energy for cows, the nervous system is dependent on glucose, and the ketones produced as a result of excessive fat metabolism can have toxic effects.This is exhibited in two main forms;

Wasting form

As the name suggests, this form results in animals losing condition. Signs include:

• decline in appetite over two to five day period
• depraved appetite, eating anything, including dirt and rocks
• selective eating, may eat hay and grass but will not eat pellets/grain
• weight loss from lack of feed
• dull coat.

Nervous form

This form of ketosis is associated with neurological signs, such as:

• apparent blindness
• incessant licking
• grinding of teeth
• circling and bellowing loudly.

When there has been an absence of significant rainfall, the nutritional value of pasture will decline considerably. In this case, it is suspected that a number of animals may no longer have been able to source sufficient feed from pasture alone, to maintain the growth of their foetus. This condition may be more common than many extensive pastoralists would suspect as loses are often sporadic and not as obvious as plant poisonings or a disease outbreak. The diagnosis of ketosis is an indication of the need to provide supplementation to animals in late pregnancy during periods when the nutritional value of pasture has declined.

Further information on ketosis, can be found on the Department of Agriculture and Fisheries.