On December 23, 2003, Secretary Veneman announced that the U.S. Department of Agriculture had diagnosed a presumptive positive case of bovine spongiform encephalopathy (BSE) in an adult Holstein cow sent to slaughter December 9 in the state of Washington. USDA News Release
The herd from which the cow had been sent to slaughter (the index herd) was identified and placed under quarantine, while a tissue sample was sent to the world reference lab for BSE in Weybridge, England, for confirmation of the diagnosis. Actions to be taken concurrent with sending the sample to Weybridge and subsequent to confirmation of the diagnosis of BSE are explained in this summary of the federal BSE Response Plan. Progress had been made in tracing the origin of the animal, its contacts, offspring and the products of its slaughter when Weybridge confirmed the USDA diagnosis on the morning of December 25. The Food and Drug Administration released a statement December 27 that rendered product from the infected cow had been contained and none had entered the commercial market.
Bovine spongiform encephalopathy (BSE), widely referred to as "mad cow disease," is a chronic degenerative disease affecting the central nervous system of cattle. The disease was first diagnosed in 1986 in Great Britain and has had a substantial impact on the livestock industry in the United Kingdom.
Secretary Veneman's BSE Containment Strategy
The first confirmed case of BSE in the United States prompted Secretary of Agriculture Ann Veneman and the USDA to make several changes to the way cattle are processed for meat. These actions were designed to prevent BSE contaminated meat from entering the food supply.
- Downer cattle are banned from the human food supply: A downer cow is one that is unable to walk for any reason. Since BSE attacks the brain, a cow with the disease has progressive ataxia (incoordination) which eventually leads to her inability to stand.
- All cattle tested for BSE must be held in containment until the test is confirmed: As part of routine inspection of animals destined for slaughter, personnel from the USDA Food Safety and Inspection Service (FSIS) conduct pre- and post-mortem examination and testing. Prior to this event, suspect cattle that were tested for BSE were allowed into the human food supply without waiting for the test results. Now, the carcass of all cattle tested for BSE must be held in cold storage until a negative test result is received. In the event of a positive test result, the carcass is destroyed.
- Declaration of Specified Risk Material: Specified risk material is prohibited from the human and animal food supply. SRM is defined as parts of the carcass that have the greatest risk of containing the prions thought to cause BSE. These risk materials are: skull, brain, trigeminal ganglia, eyes, vertebral column, spinal cord, dorsal root ganglia and small intestine.
- Tighter regulations on the use of Advanced Meat Recovery: AMR is a process in which muscle is removed from bone without incorporating any bone matter by compressing the material in a pressure chamber. The resulting product is then labeled as meat and sold for human consumption. Under the new regulations, the AMR product cannot contain any of the specified risk materials. The FSIS now has a routine AMR sampling program to ensure that the product is free of risk material.
- Air-Injection stunning is discontinued: To prevent the distribution of brain material into muscle meant for consumption, the use of air-injection stunning as part of the humane slaughter process is banned.
- Mechanically separated meat ban: Meat for human consumption may no longer be mechanically separated from the backbone. Material obtained in this manner is likely to contain dorsal root ganglia, which are a specified risk material.
Information for this section from: USDA-FSIS
Surveillance and Detection
Detection of BSE in this animal, subsequent recovery of product, and the opportunity to trace leads to now-suspect cohort animals is a success of USDA's existing routine surveillance program. However, needs for improvement in the animal identification and tracking systems were uncovered and are now being addressed. Under the safeguards announced December 30, 2003, the index cow would not have been accepted at the slaughter plant. Rather, according to the rule published January 12, 2004, the cow would have been condemned and its carcass disposed of by ``tanking,'' i.e., inedible rendering (9 CFR 314.1). The BSE-positive cow was one of three "downers" slaughtered in that day's processing of 20 cattle; the other two tested negative for BSE.More on BSE Surveillance and Detection