No person, firm, or corporation shall sell, transport, offer for sale or transportation, or receive for transportation, any carcasses of horses, mules, or other equines or parts of such carcasses, or the meat or meat food products thereof, unless they are plainly and conspicuously marked or labeled or otherwise identified as required by regulations prescribed by the commissioner to show the kinds of animals from which they were derived. When required by the commissioner with respect to establishments at which inspection is maintained under this article, such animals and their carcasses, parts thereof, meat and meat food products shall be prepared in establishments separate from those in which cattle, sheep, swine, or goats are slaughtered or their carcasses, parts thereof, meats or meat food products are prepared.