Inspection shall not be provided under subchapter I of this chapter at any establishment for the slaughter of cattle, sheep, swine, goats, horses, mules, or other equines, or the preparation of any carcasses or parts or products of such animals, which are not intended for use as human food, but such articles shall, prior to their offer for sale or transportation in commerce, unless naturally inedible by humans, be denatured or otherwise identified as prescribed by regulations of the Secretary to deter their use for human food. No person, firm, or corporation shall buy, sell, transport, or offer for sale or transportation, or receive for transportation, in commerce, or import, any carcasses, parts thereof, meat or meat food products of any such animals, which are not intended for use as human food unless they are denatured or otherwise identified as required by the regulations of the Secretary or are naturally inedible by humans.

No person, firm, or corporation shall engage in business, in or for commerce, as a meat broker, renderer, or animal food manufacturer, or engage in business in commerce as a wholesaler of any carcasses, or parts or products of the carcasses, of any cattle, sheep, swine, goats, horses, mules, or other equines, whether intended for human food or other purposes, or engage in business as a public warehouseman storing any such articles in or for commerce, or engage in the business of buying, selling, or transporting in commerce, or importing, any dead, dying, disabled, or diseased animals of the specified kinds, or parts of the carcasses of any such animals that died otherwise than by slaughter, unless, when required by regulations of the Secretary, he has registered with the Secretary his name, and the address of each place of business at which, and all trade names under which, he conducts such business.

No person, firm, or corporation engaged in the business of buying, selling, or transporting in commerce, or importing, dead, dying, disabled, or diseased animals, or any parts of the carcasses of any animals that died otherwise than by slaughter, shall buy, sell, transport, offer for sale or transportation, or receive for transportation, in commerce, or import, any dead, dying, disabled, or diseased cattle, sheep, swine, goats, horses, mules or other equines, or parts of the carcasses of any such animals that died otherwise than by slaughter, unless such transaction, transportation or importation is made in accordance with such regulations as the Secretary may prescribe to assure that such animals, or the unwholesome parts or products thereof, will be prevented from being used for human food purposes.

The authority conferred on the Secretary by section 642, 643, or 644 of this title with respect to persons, firms, and corporations engaged in the specified kinds of business in or for commerce may be exercised with respect to persons, firms, or corporations engaged, in any State or organized Territory, in such kinds of business but not in or for commerce, whenever the Secretary determines, after consultation with an appropriate advisory committee provided for in section 661 of this title, that the State or territory does not have at least equal authority under its laws or such authority is not exercised in a manner to effectuate the purposes of this chapter including the State providing for the Secretary or his representative being afforded access to such places of business and the facilities, inventories, and records thereof, and the taking of reasonable samples, where he determines necessary in carrying out his responsibilities under this chapter; and in such case the provisions of section 642, 643, or 644 of this title, respectively, shall apply to such persons, firms, and corporations to the same extent and in the same manner as if they were engaged in such business in or for commerce and the transactions involved were in commerce.