Downed Animal Protection Act - Directs the Secretary of Agriculture to promulgate regulations to provide for the humane treatment, handling, and disposition of nonambulatory livestock by a covered entity, including a requirement that nonambulatory livestock be humanely euthanized.Provides that an entity shall: (1) not move nonambulatory livestock while such livestock is conscious; and (2) humanely euthanize such livestock.Prohibits an establishment covered by the Federal Meat Inspection Act to pass nonambulatory livestock through inspection.Defines "covered entity," and "humanely euthanize."