There would be all sorts of unintended consequences from doing something like this. Look what happens to humans who feel no pain: http://www.msnbc.msn.com/id/1

There would be all sorts of unintended consequences from doing something like this. Look what happens to humans who feel no pain: http://www.msnbc.msn.com/id/16185231/ns/health-more_health_news/ http://www.msnbc.msn.com/id/16185231/ns/health-more_health_n... Then extrapolate to large herds of cattle.