Dr. Brandi New received a call this morning from the herd ma…

Dr. Brandi New received a call this morning from the herd manager of a 2400-sow farm. The farm had 40 aborted litters of mid-to-late gestation since yesterday morning. The farrowing room manager has also reported that a few litters have been farrowed “a couple of days early” with some weak and stillborn pigs. Sows in gestation are off-feed and some appear lethargic with some mild coughing noted.   Which organism do you immediately place at the top of your differential diagnosis list?