Mad cow missteps

UNIVERSAL TESTING of beef cattle for mad cow disease would add 6 cents to the price of each pound of meat. The industry resists this step, but it would be the strongest guarantee of safety, reopen US beef to foreign markets, and provide scientists with the best possible data to track and understand the disease. The recent, much-delayed confirmation of mad cow in a Texas cow that died last fall is new evidence that tighter screening is needed, as is a ban on the use of slaughtered cattle brains and spinal cords as pig and poultry feed.

The global toll of human deaths from variant Creutzfeldt-Jakob disease, which is caused by eating mad cow tissue, is fewer than 200 since it first appeared in the 1980s. The disease causes such dread, leading to bans against beef from countries that are seen as lax in limiting its spread, because it is incurable. Even though there is no record of anyone contracting variant CJD from eating US beef, the perception in nations like Japan that the United States is doing too little to detect mad cow, or bovine spongiform encephalopathy, is costing US cattlemen $3 billion a year in exports.

The United States tests about one in 90 cattle; Europe, which requires testing of all cattle 30 months or older, tests one in four; and Japan tests every animal. The US rate is a significant improvement over the one that prevailed until 2003: 1 in 1,700, when the first US case of mad cow was detected in a Washington state Holstein that had come from a Canadian farm. But the delays and contradictory results surrounding the detection of the disease in the Texas cow reduce the likelihood that nations with bans on US beef will lift them. On June 25, Taiwan reimposed a ban on US beef that it had lifted this spring.

The Texas cow was at least 12 years old, so it might have been infected by eating feed made with rendered cattle parts before that practice was banned in 1997. But it might also have been infected after that date with contaminated feed it was fed as a result of a loophole in the 1997 ban.

Cattle brains and spinal cords, the only cow parts that scientists believe carry the infection, can still be used in the feed of chickens and pigs. This can come back to cows in either of two ways. Litter from chicken factories, including food droppings, is used in cattle feed, and farmers might mistakenly feed cattle from a feedbag meant for pigs or poultry. An across-the-board ban on any animal use of rendered cattle brains or spinal cords would end this possible source of infection.

As terrible as mad cow disease is, it and variant Creutzfeldt-Jakob disease are highly preventable. Better feed practices and universal testing should make mad cow a historical footnote instead of a threat to human health and the health of the cattle business.