Pulpy kidney a risk to lambs this spring
The expected feed conditions this spring may increase the risk of pulpy kidney occurring in sheep, particularly in weaned or un-weaned lambs.
Vaccinating lambs for pulpy kidney is a cost effective way to prevent the occurrence of this disease.
Pulpy kidney, or enterotoxaemia, is a disease that causes deaths in sheep, goats and cattle.
Pulpy kidney is caused by a toxin produced by a bacterium, Clostridium perfringens type D.
These bacteria and the toxins they produce are present at low levels in the intestines of normal healthy sheep.
Under certain circumstances the bacteria are able to multiply rapidly within the intestine and produce lethal quantities of toxin which cause extensive damage to blood vessels throughout the body.
Death results from damage to blood vessels in the brain, however, the name pulpy kidney developed because the kidneys putrefy rapidly after death.
Two things are necessary for the bacteria to start rapid multiplication:
- There must be highly nutritious food material in the intestines.
- The movement of food along the intestinal tract must stop temporally.
These conditions occur most often in lambs on lush spring pastures – ones with the greatest feed intake are most susceptible – the best lambs in the mob.
Rapid feed changes predispose sheep to pulpy kidney particularly if the new feed is rich in carbohydrates.
Changes in feed should be made over a few days to reduce the risk of pulpy kidney when sheep are introduced to grain, or grain feeding is increased.
Most lambs with pulpy kidney are simply found dead, often on their side with limbs extended and head thrown back.
This is because the disease develops so quickly and convulsions and death occurs within hours of disease signs becoming apparent.
Mature sheep with pulpy kidney survive longer than lambs, but usually no more than 24 hour and may stagger and/or scour before they die.
Pulpy kidney is a preventable disease and a change in paddock and diet may stop an outbreak.
However, giving lambs two pulpy kidney injections prior to a high risk period like spring is a cost effective husbandry tool.
Without vaccination, deaths from this disease could reappear later in summer when fed grain.
The vaccine is available in various combinations:
- With tetanus and cheesy gland (CLA) vaccine (3-in-1 vaccine).
- With other clostridial vaccines, such as that for tetanus, blackleg, black disease and malignant oedema (6-in-1 vaccine).
- With selenium and vitamin B12 (or both).
- With moxidectin (in an injectable form) to treat worms.
Sheep not previously vaccinated must have two injections, four to six weeks apart, to achieve high-level immunity for 12 months.
To maintain immunity, booster doses are needed at yearly intervals. Giving annual booster injections over the next two years should protect sheep for life.
For more information go to the Pulp Kidney webpage on the Department of Agriculture and Food, Western Australia's website.
For more information contact Danny Roberts, Veterinary Officer, Albany on +61 (0)8 9892 8535.