Just some added info for the city folks
How to Use Cattle Ear Tags for Identification
By Frank Whittemore, eHow Contributor
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Each ear tag is a unique identifier for each head of cattle.
Today, it is the law that cattle are tracked from birth to slaughter to help protect both the health of each animal and the health of the public that will eventually purchase the products made from that animal. For this reason, cattle ranchers use ear tags to mark each and every head of cattle with a unique identifier that allows them to track every aspect of the animals' lives, including age, health status, veterinary treatments, feeding schedules, relocations, and sales. Many of these tags also contain Radio Frequency Identification Devices or RFIDs that help to track cattle electronically.
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