Mad Cow Diseaseó BSEó

Is this a real threat?

What is BSE?

BSE is a nervous disease of cattle that has never been diagnosed in South Africa

Bovine spongiform encephalopathy (BSE) is a nervous disease of cattle. It is caused by an agent that differs distinctly from conventional infectious agents.

The disease was first reported in 1985 in the United Kingdom (UK). Since then more than
180 000 BSE cases have been confirmed in the UK alone. BSE has also since been reported from other countries. Most of these countries are, however, regarded as low-risk countries because of their strict slaughter-out policy. This disease has never been diagnosed in South Africa or any other country in Africa.

How do cattle contract the disease?

Cattle probably became infected after eating rations that included scrapie-infected material

Cattle in the UK contracted this disease when carcass meal obtained from sheep suffering from a similar disease (scrapie) was included in their rations. The disease was then propagated by feeding meat and bone meal (MBM) from diseased animals to healthy cattle. It takes years for cattle to show symptoms of the disease.

South Africa is free from scrapie.

There is no evidence that cattle can infect one another with BSE.

What are the symptoms of BSE?

Nervous symptoms appear over a long period and characterise the disease

The period from infection to the development of symptoms of the disease may be as long as 8 years. Once the animal shows signs of the disease it can be sick for a period ranging from 2 weeks to 6 months. The disease is always fatal. Affected cattle display changes in temperament and sometimes become aggressive. Some display nervousness and become wary of human handling, while others are sensitive to light or sound.

Cattle with BSE show abnormal posture and un-coordinated movement with a swaying gait.
They have difficulty rising.

Rabies, some blood parasites and certain poisons can cause similar symptoms in cattle.

How is the disease diagnosed?

A suspected diagnosis can be made in the live animal on the basis of the clinical symptoms

It is not possible to isolate the causative agent from or demonstrate its presence in blood or any other tissue in a live animal. A suspected diagnosis is made on the basis of the clinical symptoms. After the animal has died or been destroyed, a microscopic examination of the brain is essential to confirm a diagnosis of BSE.

Can mad cow disease be transmitted to humans?

A definite link between BSE (in cattle) and Creutzfeldt-Jakob disease (in humans) has not been proven. Suspicion of such a link is, however, the cause of worldwide concern.

How are we preventing BSE from entering the country?

Very strict import control measures and continuous disease surveillance prevent the introduction of BSE into South Africa

The Department of Agriculture has banned the importation of cattle, beef and beef products from the UK and any other country that cannot prove that it is free of BSE.

What other measures are taken to minimise the risk of BSE in South Africa?

An active targeted surveillance programme has been instituted by Veterinary Services according to international standards and recommendations of the World Organisation for Animal Health (OIE)

This programme monitors any suspicious cases and assists in continuously reaffirming the absence of BSE from South Africa. You can help with these efforts by immediately reporting all cases of strange behaviour in cattle to your nearest state veterinarian or animal health technician.

As a further precaution farmers in South Africa are not allowed to feed meat and bone-meal from the remains of cloven-hoofed animals to their livestock.

For further information contact:

The Senior Manager
Directorate of Animal Health
Private Bag X138
Pretoria
0001

 

This publication is available on the web at: www.nda.agric.za/publications

2003 (Revised)

Compiled, printed and published by the
Directorate Agricultural Information Services
Department of Agriculture
and obtainable from Resource Centre 
Private Bag X144, Pretoria, 0001 South Africa