Abstract: Bi-directional cattle traceability process comprising five basic stages: a first document traceability and sanitary certification chain stage, wherein the animals are identified by birth certificates, animal identification attached to the animal's ear and registered in a data centre. A second stage for transfer of animals to another establishment, wherein genetic material is extracted from the offspring not yet weaned, filed and registered and registered in the data centre. A third stage for slaughtering of animals, wherein the slaughtered animal's ear is cut off where the animal identification is attached and the animal identification is read on line, the half carcases have sealed strips applied to them, DNA samples are extracted from the animal, then deposited in the official genetic bank and on each cut a locket sampler is attached encrypting a genetic and biochemical sample.