• The BSE positive cow was born and raised in a herd in Texas and was approximately 12 years old, according to information obtained from the owner. It was sent to a 3D/4D pet food plant in Texas and was selected for sampling on arrival.
  • The animal was non-ambulatory and did not enter the human food or animal feed chain. The remains of the animal were incinerated.

Epidemiological Investigation

  • USDA will be working closely with the Texas Animal Health Commission and the herd owner to begin tracing any animals of interest for testing. The source herd is now under a hold order as we identify animals of interest within the herd.
  • Animals of interest would include any other animals that were born the same year as this animal, as well as any born the year before and the year after. Animals of interest would also include any of this animal’s offspring that were born within the last 2 years.
  • If the age of the animal cannot be pinpointed, then USDA will expand the inquiry to include all animals in this herd before the feed ban went into place in 1997.
  • USDA will also work with the Food and Drug Administration in an effort to determine the feed history in this herd. Given the animal’s age, it was most likely infected by consuming feed prior to the implementation of the ruminant–to–ruminant feed ban in 1997.


  • The animal was tested for BSE on Nov. 19, 2004, as part of USDA’s intensive surveillance effort.
  • Initial test results from a BSE ELISA rapid test were inconclusive. The sample was then sent to USDA’s National Veterinary Services Laboratories (NVSL) for further testing. Two Immunohistochemistry (IHC) tests were conducted and both were negative for BSE.
  • At the recommendation of the Inspector General, the animal was retested with a second confirmatory test, the Western blot. The results announced on June 10, 2005 were reactive.
  • Additional testing by the United Kingdom’s reference laboratory in Weybridge, England and NVSL confirmed on June 24, 2005 that the animal was BSE positive but that the level of infection was low.
  •  Due to the fact that this animal was sampled at the same time as four other animals and parts of the carcass were stored together, USDA made the decision to conduct DNA confirmatory testing before announcing the state of origin.
  • DNA testing has now verified that USDA correctly identified the positive animal.

USDA's Veterinary Services