The U.S. Department of Agriculture (USDA) has reported an atypical case of bovine spongiform encephalopathy (BSE), or “mad cow disease,” a neurologic disease of cattle, in a six-year-old mixed-breed beef cow in Florida. This animal never entered slaughter channels and at no time presented a risk to the food supply or to human health in the U.S., stressed the USDA. According to the USDA Animal and Plant Health Inspection Service’s (APHIS) National Veterinary Services Laboratories (NVSL), the cow was confirmed positive for atypical H-type BSE. The animal was initially tested at the Colorado State University Veterinary Diagnostic Laboratory (a National Animal Health Laboratory Network laboratory) as part of routine surveillance of cattle that are deemed unsuitable for slaughter. APHIS and Florida veterinary officials are gathering more information on the case. Two forms of bovine spongiform encephalopathy BSE is not contagious and exists in classical and atypical types, according to the USDA. Classical BSE is the form that occurred primarily in the U.K., beginning in the late 1980s, and it has been linked to variant Creutzfeldt-Jakob disease in humans, the organization stated. The primary source of infection for classical BSE is feed contaminated with the infectious prion agent, such as meat-and-bone meal containing protein derived from rendered infected cattle, USDA said. Regulations from the Food and Drug Administration (FDA) have prohibited the inclusion of mammalian protein in feed for cattle and other ruminants since 1997 and also have prohibited high-risk tissue materials in all animal feed since 2009. Atypical type Atypical BSE generally occurs in cattle that are eight years of age or older and seems to arise rarely and spontaneously in all cattle populations, the USDA stated. This is the nation’s sixth detection of BSE, according to the USDA. The first, in 2003, was a case of classical BSE in a cow imported from Canada; the rest have been atypical (H- or L-type) BSE, the organization stated. The World Organization for Animal Health (OIE) recognizes the U.S. as negligible risk for BSE. Atypical BSE cases do not impact official BSE risk status recognition, as this form of the disease is believed to occur spontaneously in all cattle populations at a very low rate, according to the OIE. Therefore, this finding should not lead to any trade issues, stated the organization. Download the USDA’s BSE factsheet to learn more.
