In several isolates of Mexican AI, ARS scientists found the mutant gene. This new genetic clue to AI's severity may open the way to predicting which strains are likely to become poultry killers, just as health agencies routinely predict severe strains of human influenza. ARS scientists found that AI virus uses a genetic mutation mechanism similar to that of the human flu. A relatively weak AI virus binds only to respiratory tract or gut cells. ARS researchers flushed out these cells, called alveolar macrophages, and in laboratory tests were able to identify the virus in them when other tissues in the pig apparently were virus-free.
Pigs can be long-term carriers of the virus without showing signs of disease.
A toxin made by fungi that can infect corn disrupts an essential fat in mammals. This discovery by ARS and Emory University scientists may lead to reducing the disease threat posed by the toxin, called fumonisin. Five years ago, scientists learned that high levels of fumonisin are the direct cause of rare outbreaks of disease in farm animals. The outbreaks had long been tied to animal feed, such as broken corn kernels called screenings, infected with Fusarium fungi. Several dozen horses in Kentucky and Virginia died earlier this year after eating Fusarium -tainted screenings.