It is mandatory to test all show & breeding stock sale cattle here in NY. It was prevalent back maybe 15 yrs ago, but I have not "heard" of anyone having a problem for a while. But, I know our state jumped on testing & warning producers many years ago. (knock on wood), I have tested all my bulls & heifers (not steers) for maybe 11-12 years now with no positives. I don't test the steers, because I have never had a positive, and most all the dams have been tested. Several steers do end up getting tested because they get purchased by 4-H'ers.