There is Simmental-sourced literature discussing AM dating as far back as the mid-1980s; however, no documented cases have been established.  In 2008, the American Angus Association verified the presence of AM in two very popular sires.  These sires and their resulting generations of progeny, grand progeny, etc. have spread AM in many Angus pedigrees.  Consequently, Angus genetics entering into the ASA database, either commercial females bred to SimGenetic bulls, or registered Angus bulls and cows used to develop SimnAngus could carry AM.  

Because the ASA has an open herdbook, allowing other breeds into our database and percentage pedigrees, AM could be a risk in certain cattle.  We strongly suggest using ASA’s website Animal Search function to access the most up-to-date genetic abnormality-status for each animal in our database.

Reporting Abnormal Calves: Call ASA immediately. ASA will reimburse all expenses. Take photos or video that best display the abnormality. We will need DNA (hair or tissue) from the calf, dam and sire. (We have DNA on all A.I. sires and donor dams.) If the calf is dead, chill the carcass until ASA has been contacted.