Animals > Animal Diseases > Bovine Spongiform Encephalopathy > Safeguards  

General Information

Surveillance Objectives

In 1992, Canada implemented a national BSE surveillance program based on internationally recognized science. The program was delivered through the collaborative efforts of federal and provincial governments, universities and private veterinary practitioners. The level of testing exceeded the international requirements recommended by the World Organization for Animal Health (OIE) and was clearly appropriate to a country with no cases of BSE. The primary objective of the surveillance program was to determine whether BSE was present in Canada. Prior to May 2003, over 10,500 animals were tested for BSE. All tested negative.

The detection of BSE in May 2003 in a cow born and raised in Canada confirmed the presence of a previously undetected level of the disease in this country. Although the prevalence of the disease is estimated to be extremely low, this must be confirmed through increased BSE surveillance.

In January 2004, the Government of Canada announced that it would enhance its BSE surveillance testing to at least 8,000 cattle during the first year and to 30,000 per year in subsequent years to calculate the prevalence of BSE in Canadian adult cattle. The level and design of this enhanced program continues to be in full accordance with the guidelines recommended by the OIE. In 2004 there were 23,550 samples collected and tested. In 2005, the minimum target of 30,000 samples was surpassed in early June.

Enhancing BSE surveillance testing is the only way to demonstrate to both domestic and international markets that the prevalence of BSE in Canada is extremely low. Increasing surveillance testing will contribute to the general understanding of the disease in Canada. It will also influence future disease control activities and provide a method to monitor and evaluate the effectiveness of BSE preventive actions currently in place.

Canada’s BSE-related Actions

Canada has implemented several measures to protect food safety and animal health. These measures are based on internationally accepted science. They also reflect the experiences of other BSE affected countries.

Food Safety

Food is kept safe from BSE by the removal of specified risk materials (SRM) from all cattle at slaughter. SRM are tissues that, in BSE-infected cattle, contain the BSE agent. SRM include the skull, brain, trigeminal ganglia, eyes, tonsils, vertebral column, spinal cord, and dorsal root ganglia of cattle older than 30 months of age. The small intestine of cattle of all ages is also removed.

In Canada, SRM are removed from every animal slaughtered for human consumption. This measure is internationally recognized as the most effective means to protect public health from BSE.

Animal Health

Canada’s animal health safeguards focus on reducing the risk of the disease spreading among Canadian cattle. Research suggests that the most likely route of BSE transmission is through the ingestion of feed contaminated with the BSE agent. In 1997, Canada implemented a feed ban based on the recommendations of the World Health Organization (WHO). The ban is in place to prevent the spread of BSE through feed. It prohibits the feeding of certain mammalian protein by-products to ruminants (e.g., cattle, bison, sheep, goats, elk, and deer).

The ban requires feed containing prohibited materials to be labelled with a warning which states that the feed must not be fed to cattle, sheep, deer, or other ruminants. In addition, renderers, feed mills, feed retailers and producers must keep detailed records of how feed is used, produced and sold.

In July 2004, the Government of Canada announced its intent to expand the restrictions to preclude the use of bovine specified risk materials in the production of feeds for all classes of livestock and pet food. When implemented, this approach will eliminate any inadvertent exposure of cattle to prohibited materials that could arise due to cross contamination or human error.

Higher-Risk Animals

Canada’s surveillance program targets animals at highest risk of being infected by BSE. Focussing on these populations better enables Canada’s surveillance program to provide a more accurate estimate of the prevalence of the disease in the country and increases the likelihood of detecting further cases, should they exist. This approach ensures that Canada is looking for BSE in the places where we are most likely to find it.

Higher-risk animals include:

• cattle of all ages displaying clinical signs consistent with BSE (for example, behavioural changes including excitability and anxiousness, and emaciation)
• cattle over 30 months of age from the 4-D categories:
  • animals found dead (dead stock)
  • animals that are non-ambulatory (downers)
  • animals presented for emergency slaughter (distressed or dying)
  • animals sent to slaughter and found to be sick at the ante-mortem inspection (diseased)