Inspection shall not be provided under this article at any establishment for the slaughter of poultry or the processing of any carcasses or parts or products of poultry which are not intended for use as human food, but such articles shall, prior to their offer for sale or transportation in intrastate commerce, unless naturally inedible by humans, be denatured or otherwise identified as prescribed by regulations of the board to deter their use for human food. No person shall buy, sell, transport or offer for sale or transportation or receive for transportation, in intrastate commerce, any poultry carcasses or parts or products thereof which are not intended for use as human food unless they are denatured or otherwise identified as required by the regulations of the board or are naturally inedible by humans.