May 28, 2003

 

Look for Credible Information on Cow Disease, Livestock Specialist Urges

Beef producers, consumers and others interested in the outbreak of mad cow disease in Canada, need to be cautious about information and reports about the disease, says a North Dakota State University beef specialist.

"This is a serious disease that raises concerns for cattle producers because of the threat to their livelihood and consumers because of the potential threat to their health," notes Greg Lardy of the NDSU Extension Service. "Reports on the disease have included some incorrect information and we’re hearing some misconceptions about the disease and how it is spread. The serious nature of the disease lends itself to speculation and rumor"

Lardy explains that mad cow disease, known as bovine spongiform encephalopathy (BSE) is a disease condition in cattle which is thought to have originated in Great Britain. It occurs in cattle between two and eight years old and is always fatal. The most plausible cause of the disease is a prion, a self-replicating protein, rather than a bacterium or virus.

Meat and milk have not conclusively been shown to carry the infective agent. Measures have been taken in the United States to exclude those parts known to carry the infective agent, primarily the brain and central nervous system tissue, from the food and feed supply, Lardy notes. "Inspections that reveal the presence of those tissues lead to the condemnation of food and feed products."

"There is still debate in the scientific community regarding how BSE is spread," Lardy says. "BSE is thought to be spread in tissue from the central nervous system, some of which can be present in meat and bone meal. BSE is not spread by animal to animal contact.

Medical research has focused on the possible link between BSE and new variant Creutzfeld-Jacob disease (nv-CJD). Pathological similarities exist between the two conditions, which has led scientists to speculate that the two conditions are related. The disease is different from Creutzfeldt-Jacob disease (CJD), another spongiform encephalopathy that affects humans. That disease affects humans naturally and occurs in about one in a million people because of a genetic mutation.

Lardy notes that since 1989, the United States has prohibited importation of ruminants and most ruminant products from countries affected by BSE. As a precautionary measure, the Food and Drug Administration implemented a ruminant to ruminant feeding ban for meat and bone meal in December 1997, prohibiting the feeding of ruminant-derived meat and bone meal back to ruminants. Also in May 1990, the USDA’s Animal Plant Health Inspection Service banned importation of live ruminants and most ruminant products from other European countries.

Since May of 1990, the United States has had an aggressive surveillance program to ensure timely detection and response in the event that BSE is ever detected in the United States. The surveillance program is based on sampling brains of cattle with suspicious neurologic symptoms.

"If you are concerned about this disease and its effects, educate yourself on what is known about BSE," Lardy says. A number of agencies and organizations provide information about BSE on the Web. They include:

NDSU at www.ext.nodak.edu/extpubs/ansci/beef/as1206w.htm

USDA/APHIS Veterinary Services at www.aphis.usda.gov/oa/bse/

Centers for Disease Control and Prevention at www.cdc.gov/ncidod/diseases/cjd/cjd.htm

U.S. Food and Drug Administration at www.fda.gov/cvm/index/bse/bsetox.html

###

Source: Greg Lardy, (701) 231-7660, glardy@ndsuext.nodak.edu
Editor: Tom Jirik, (701) 231-9629, tjirik@ndsuext.nodak.edu