The head, tail, tongue, thymus gland and all viscera of each slaughtered animal, and all blood and other parts of the animal to be used in the preparation of meat food products or medical products shall be handled in such a manner as to identify them with the rest of the carcass and as being derived from the particular animal involved until the postmortem examination of the carcass and parts thereof has been completed. The handling shall include the retention of ear tags, back tags, implants and other identifying devices affixed to the animal, in such a way as to relate them to the carcass.
7 Pa. Code § 1.112
This section cited in 7 Pa. Code § 1.113 (relating to procedure for identification).