01/05/07 BSE-free cattle research

The word is out, news that a dozen cows have been genetically engineered to be free of the protein that causes BSE or mad cow disease as some call it. Scientists say they have 'knocked out' the gene responsible for making proteins called prions. The disease didn't take hold when two of the cows were exposed to bad prions. Doctor Juergen Richt of the USDA National Animal Disease Center in Ames, Iowa was the lead author of a report that examined research done by a South Dakota biotech company, Hematech, Inc. RICHT "In summary we found that these animals developed normally, same weight gain as their wild types. They eat normal, they walk normal, they have normal immune responses to various antigens." A dozen calves with the prion gene knocked out are now being studied at the Iowa lab. RICHT "The big question is are these animals viable and are they susceptible to prion diseases or not? That is the next step." Three of the original dozen were slaughtered so their brains could be studied and the remaining nine are being injected directly with mad cow disease to make sure they are immune to it. It's still going to be years before the full test results are in but this research may help scientists better understand similar brain wasting diseases in humans. Today's Idaho Ag News Bill Scott