What are the numbered ear tags method divided into

Numbered ear tags are one of the animal identifiers. The numbered ear tags are used to prove the identity of the livestock and carry the individual information of the livestock. It is applied to the ears of the livestock.

The numbered ear tags method has the following points:
1. Metal ear tags: metal numbered ear tags are used to sterilize the appropriate position of the sheep's ears and then punched and installed, but the blood vessels should be avoided. Metal numbered ear tags can be worn after uniform numbering before use. Field number, year number, and individual number can be played on numbered ear tags. The individual number generally represents the ram in the singular number and the ewe in the even number. The total number of words should not exceed 8 digits, which is conducive to the computer management of data. Now take the numbering system of Nanjiang Yellow Goat as an example.
2. Plastic card method: Before wearing, use a special writing pen to write the ear tag, and use the special ear tag tongs to wear on the sheep's ear. The numbering method is the same as above. For sheep grazing in the shrubland of hilly and mountainous areas, double ear tags can be worn to prevent the numbered ear tags from falling off and causing losses to breeding and production management.
When clamping numbered ear tags, be careful not to press the ear tags against the edge of the animal's ears, so as to avoid necrosis of the pressed part and the ear tags to fall off.