Sep 8, 2005 (CIDRAP News) Meat companies are again free to use most of the small intestine of cattle to make sausage casings, following a change in a federal rule intended to protect people from exposure to bovine spongiform encephalopathy (BSE), or mad cow disease.
The US Department of Agriculture banned the use of the small intestine of cattle in food shortly after the first US case of BSE surfaced in December 2003. Later, in July 2004, the Food and Drug Administration banned use of the small intestine in food supplements and cosmetics.
This week, both agencies announced that only the distal ileumthe last few feet of the small intestinewill be banned from those products henceforward. Researchers have found that the distal ileum is the only part of the intestine that contains the BSE agent in infected cattle, and the agencies said the distal ileum can be safely removed from the rest of the intestinal tract.
Eating meat products from BSE-infected cattle is believed to be the cause of variant Creutzfeldt-Jakob disease, the human equivalent of BSE. The brain diseases are incurable and always fatal.
The USDA Food Safety and Inspection Service (FSIS) said it "has determined that the portion of the small intestine traditionally used as food, or as a casing for specialty sausage, can be safely and effectively separated from the section that contains the distal ileum." This provides just as much protection as removing the entire small intestine, the statement added.
The agency said it will now require removal of the lower 80 inches of the small intestine. Businesses will have to demonstrate that they have written procedures for this. Besides US companies, foreign companies eligible to export beef to the United States will be subject to the revised rule, the FSIS said.
"The procedure is typically completed while the small intestine and large intestine are still attached [to the carcass], so there's no chance that personnel would measure and cut from the wrong end," FSIS spokeswoman Amanda Eamich told CIDRAP News.
In the meat industry, cattle intestines are used mainly to make natural casings for sausage, mostly for ethnic markets, according to Dr. Morris Potter, lead scientist for epidemiology in the FDA's Center for Food Safety and Applied Nutrition.
Though the small intestine can also be used in cosmetics, Potter said he was not aware of such use. However, dietary supplement makers harvest some enzymes from beef intestine for use in their products, he added.
Potter said the distal ileum makes up only a small part of a cow's small intestine. It ranges from 3 to 6 feet in length, while the main portion, called the jejunum, is 80 to 150 feet long.
In studies in which calves were fed material from BSE-infected cattle, the distal ileum was the first tissue where signs of the disease showed up, according to Will D. Hueston, DVM, a BSE expert and director of the University of Minnesota Center for Animal Health and Food Safety in St Paul.
The BSE agent was detected in the distal ileum as soon as 6 months after exposure, Hueston said, adding, "The agent has not been detected in other parts of the intestine." The wall of the distal ileum contains patches of lymphoid tissue that are thought to be involved in disseminating the BSE agent through the body, according to a research summary from the United Kingdom Department of Food, Environment and Rural Affairs.
The FSIS said the rule change is consistent with BSE-related guidance from the World Organization for Animal Health (OIE) in its 2005 Terrestrial Animal Health Code.
The change takes effect Oct 7, and the FDA and FSIS will take comments until Nov 7.
Sep 7 FSIS news release
Sep 6 FDA news release