Ear tag

An Ear tag is a plastic or metal object used for identification of animals. If the ear tag contains an RFID module conforming to ISO 11784 & 11785, then they are called Electronic Ear Tags. Ear tags usually carry the individual identification number of the animal. This identification number (ID) should be assigned by a national organisation to keep them unique. However, if animals are tagged for internal purposes in a herd or farm, IDs need not be unique in larger scales.
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Common minor anomaly, a rudimentary tag of ear tissue, often containing a core cartilage, usually located just in front of the ear (auricle). Therefore also called preauricular tag. The presence of 2 or more minor anomalies in a child increases the probability that the child has a major malformation.