Amplifying Processing of Livestock in the United States Act or the A-PLUS Act This bill directs the Department of Agriculture to revise federal regulations related to market agencies owning, financing, or participating in the operation of a meat packing entity. Specifically, this bill allows market agencies to have an ownership interest in, finance, or participate in the management or operation of a packing entity if such packing entity has a cumulative slaughter capacity of less than 2,000 animals per day or 700,000 animals per year.