EID Tags: The Who, What, When, Where & Whys

For decades, ear tags have been used for identification of livestock and other animals.  It commonly carries an animal identification number (AIN) or code for the animal, therefore forming an unique identity.  They also ensure traceability in order to help prevent theft and to control disease outbreaks. The first ear tags were primarily steel with nickel plating, but have come along ways since the 1900s.  Today they come in a variety of designs, including flag-shaped, button-shaped, plastic clip ear tags, and metal ear tags.  However, the newest design involves the use radio frequency identification technology and are commonly known as Electronic Identification ear tags. 

What are EID Tags?

Electronic identification ear tags and tag reader

Electronic Identification ear tags (EIDs) are small, button-like tags that are placed in the animal's ear.  Each EID tag has a unique 15-digit number printed on it, which is a specific identification for that particular animal (Roberts, Wallace, Harba & Paterson, p. 2).  The number can be read not only by sight, but also with an electronic tag reader.  Leading EID tag readers include a memory capability that allows for storing of scanned electronic ID values.  After working the livestock, a list of EID tags that were scanned can be downloaded onto a computer.  Events can then be applied, such as medical treatments or update pasture locations for the animals that were worked. 

 

Where are they placed? 

Depending on user preference, EID tags can be placed in either the right or left ear of the animal.  The tags are put into the ear using a tagger, which is simply a handheld device with a blunt pin attached.  It does not harm the animal or cause pain, and is no different than piercing human ears.  Before tagging, both the tags and applicator should be dipped in disinfectant to ensure proper healing. The EID tag should be placed close to the head, approximately 1/3 to 1/2 of the ear length out from the base, in the middle of the ear vertically (Roberts, Wallace, Harba & Paterson, p. 4).  Below is an example of the correct position to place the tag in an ear:

Correct EID tag placement in the ear of livestock.

 

Who Uses Them?

A ranch worker scanning the EID tag of a bull being processed

Traceability is becoming a more common practice in the livestock industry now-a-days. 

When and Why should they be used? 

Livestock identification has both visual and management benefits.  EID tags offer another form of identification for each animal.  Sometimes visual tags get lost get snagged on a fence, etc, whereas EID tags are small and are desgined for high retention rates.  In addition, being able to track an animal's history and performance helps determine which ones are performing well.  While using blank tags and marking pens offer maximum flexibility in numbering cattle, ink fades over time and makes it hard to read tags in the pasture.  

Also, the continuous need for improvement in management and production practice is contributing to the increasingly popular use of EID tags,  especially the cattle industry. By scanning the tag with a reader, the animal doesn't need to be completely still in order to read the tag or a tattoo number.  Scanning them, instead of writing tag numbers down, is a tremendous benefit in saving time and minimizing errors.  Overall, electronic identification tags are simple, reliable, and extremely accurate!

References: 
A. J. Roberts, L. E. Wallace, M. Harba, and J. A. Paterson. Case Study: Retention and readability of radio frequency identification transponders in beef cows over a 5-year period. Professional Animal Scientist 2012 28:221-226.

Pictures taken from: http://www.depi.vic.gov.au/agriculture-and-food/farm-management/national-livestock-identification-system/nlis-cattle/your-guide-to-victorias-cattle-identification-legislation