USDA/APHIS Nebraska Office Provides BSE Surveillance and Collection InformationThe United States and Canada took action in 1997 to reduce the probability that bovine spongiform encephalopathy (BSE) would be transmitted through contaminated feed. However, in 2003 two cases of BSE were discovered in North America. Although it is unlikely that an outbreak of any magnitude will be observed, it remains extremely important that veterinarians and livestock producers be vigilant for new cases of bovine spongiform encephalopathy.
Veterinarians should consider BSE in the list of diagnostic differentials when cattle exhibit signs of behavioral changes, ataxia, or recumbency. Clinical signs include changes in temperament (apprehension, nervousness, unwillingness to move through doorways, belligerence), drooling, itching of the head, fine muscular tremors, moaning, rapid respiratory rate, slow heart rate, incoordination, abnormal postures, abnormal gait, decreased milk production, loss of body condition despite a normal appetite, and death. The incubation period ranges from 2 to 8 years and the health of affected animals typically deteriorates over a period of 2 weeks to 6 months. Most cattle affected are between 3 and 6 years old. From the AVMA website BSE Backgrounder.
BSE is reportable as a foreign animal disease. If you suspect that an animal may have BSE, contact the USDA/APHIS/VS office (in Nebraska call 402- 434-2300) or the Nebraska Department of Agriculture, Bureau of Animal Industry (402-471-2351). The diagnosis is made by microscopic examination of stained brain tissue collected post-mortem. The tissue required is from the obex at the base of the brain-stem and underneath the cerebellum. It should be fixed in formalin. Attached are photographs and diagrams to aid in the collection of the appropriate tissue and also aids for estimating the age of cattle.
