One suggestion he offered was looking at whether state practice acts are being violated. According to Dr. Vaughn, the CVM's enforcement priorities are directed at individuals who cause a violative residue or use a fluoroquinolone in an extralabel manner in a food animal. Discussion of bovine spongiform encephalopathy was next on the program. Risk communication is the greatest challenge, he said. The next major challenge involves the limits of scientific methodology, he said.
Science moves ahead by disproving hypotheses.
Scientific method does not allow us to prove safety. He reminded bovine practitioners of their importance in reporting suspicious neurologic cases. We're dealing with a swarm of viruses. Using case reports, he discussed malignant catarrhal fever virus, coronavirus, bluetongue virus, and bovine immunodeficiency virus. Dr. Ellis noted that a problem has developed with efficacy of coronavirus vaccines for calves, and that respiratory tract disease is an apparently new manifestation of coronaviruses in cattle.