166.15  Prohibited sales.
  No biological products shall be sold, offered for sale, distributed, or used, unless produced at a plant which, at the time of producing, held a United States department of agriculture license for the manufacture of such biological products.
[SS15, §2538-w3; C24, 27, 31, 35, 39, §2719; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §166.15]