Chapter 5 of Title 21 of USC prohibits the preparation and sale of worthless or harmful products (virus, serum, toxin, or analogous product) for domestic animals without a permit of the Secretary of Agriculture and introduces other measures for the protection of quality of animal food. The Secretary of Agriculture is authorized to cause the Bureau of Animal Industry to examine and inspect all viruses, serums, toxins, and analogous products, for use in the treatment of domestic animals, which are