Managing Cattle Enterprise Risk with Electronic Animal Identification
* Tags
* Reader
* Data accumulator
* Software
Each part provides a vital role in an effective RFID system: the tag is placed on the animal, the reader wirelessly scans the tag, the accumulator records the tag id given by the reader, and the software makes profitable use of the information. Each part can vary considerably in price and features. In addition, each part has to be compatible with the part before it.
Commercial RFID solutions for cattle are extremely similar; most RFID possibilities are not represented. As such, it is probably best to use this information to compare products, not for describing the feature set that you will try to find.
Tags
The manufacturer of the tag gets to choose what properties the tag possesses. There are two standards, ISO 11784 and ISO 11785, that a manufacturer has the option of following. ISO 11784 dictates how the identification number is formatted and ISO 11785 dictates radio properties of the tag. The importance of these standards is that they allow all products that comply with the standards to work together. So the easiest thing to do is to get ISO compliant tags and reader and be done with it. Typically these standards are used anyway, but since they are not required a tag can vary in these ways:
* Frequency
* Location on animal
* Active v. Passive Mode
* Full v. Half Duplex
* Data storage
Frequency
There are three general frequency bands that a tag can fall under: low, intermediate, and high. The low band has a short to medium read distance, is inexpensive, but has a slow speed. ISO 11785 tags use this band. The intermediate band has a short to medium read distance, can become inexpensive, and has a faster speed. The high band has a long read range and has an even faster speed, but it is expensive and requires line of sight.
Location on animal
RFID chips can be a ear tag, injectable transponder, or rumen bolus. A ear tag goes on the ear as conventional ear tags. This is a very simple tag to place on an animal. An injectable transponder is made to be injected into the animal’s body. It can be placed in the hoof, umbilical region, poll, or caudal fold. The main worry of injectable transponders is the possibility of movement and loss of the chip, which would cause problems at slaughter. A rumen bolus has even larger problems of removal during slaughter.
Active v. Passive Mode
An active tag has a battery that it uses to transmit its signal. This allows it to be read from longer distances. Unfortunately, this raises its cost, gives it a maximum possible life of 10 years, and increases its size.
A passive tag does not have a battery. Instead, it is powered by readers. For
a passive tag, a readers send out a radio signal which powers the tag just enough
to send its signal back to the reader. This cannot be read from as long of distances,
but cuts down on cost, does not limit its life, and decreases its size. ISO
11785 tags are passive.
Full v. Half Duplex
The duplex of a tag involves how it transmits its signal. This means that the
reader needs to have the same duplex as the tag. In short, Full Duplex (FDX-B)
is faster and more expensive, while Half Duplex (HDX) is slower and more inexpensive.
The difference in duplex could cause problems because the tag and reader have
to agree, however, a standardized ISO 11785 reader is required to be able to
read both, reducing possible problems.
Overview of Full and Half Duplex TagsDuplex Protocol Speed Relative Cost
Full FDX-B Faster More expensive
Half HDX Slower More inexpensive
Data Storage
The id format can vary. Any company can make any id format they wish. ISO 11784 has been the leading format for id numbers in tags, however, the proposed USAIP format varies slightly from ISO 11784 in that it has an extra error checking feature.
Tags can store just an id or an id along with data. Storing data along with the tag increases its cost, but also could be used for storing permanent or temporary information. ISO 11784 tags do not have this feature.
If you choose an id along with data, you then have the choices of read-write
and write once data. Read-write data could be edited and rewritten, but this
would make tampering easier and cost more. It would, however, allow for keeping
the herd’s records on each individual cow, which has many applications
in the field when the records may otherwise be inaccessible. Write once data
could only be written to once, and thus would limit the types of information
to store on it.
Reader
An RFID reader must be compatible with the RFID tags. RFID readers can be ISO 11784 and ISO 11785 compliant as well. If a reader is ISO compliant, it will work with any ISO compliant tag.
RFID readers can vary in:
* Read range
* Mobility
* The possibility of reading multiple tags at once
Read range
RFID readers have a wide range of maximum reading distances. This is completely up to the manufacturer. A further read distance should increase the price, but it will also use more power.
Mobility
Readers normally come in two types, mobile and stationary. Mobile readers are normally less costly and more useful, but stationary readers can have a longer read range and more features.
The possibility of reading multiple tags at once
Most mobile readers can only read one tag at a time, which is all that is needed since they typically have a short read range. However, higher end stationary readers are able to read multiple tags at once. These are useful when monitoring cattle moving through a wide chute.
Data Accumulator
A data accumulator can be anything from a computer to a clip board, although a clip board removes many of the benefits of RFID. Normally a computer or palm pilot would be used based on the reader and location where reading is taking place. The data accumulator merely obtains the IDs from the reader for input into the software system. Many readers can remove the need for this part of the process by keeping track of all read identification numbers. No matter what, however, there must be a way for the identification numbers read to get to the software.
Software
The software is where the profit of RFID systems comes. Software can keep track of statistics of each cow and herd and can help one make decisions. Software varies widely. It would probably be best to visit RSID in Practice | Software or look at cattle specific products in Useful Links
Conclusion
Although there are many options in the RFID industry, not all may be represented. Having a look at the list of links concerning companies and seeing what is offered for what price is the next step in figuring out what you want.
Sources
Dale A. Blasi, Kevin C. Dhuyvetter, Mark F. Spire, Marc P. Epp, and Brian B. Barnhardt. 2003. A Guide for Electronic Identification of Cattle. Kansas State Research and Extension