When the Chips are Down: Equine Identification

Using microchip technology as a form of equine identification is quite popular in Europe. However, the widespread use of electronic identification systems for tracking diseased or stolen horses, show horses, or horses in transit has been slow to gain acceptance among U.S. equine enthusiasts. Microchip proponents and opponents agree that the inability of one manufacturer's microchip scanner to read a competitor's micro-chip is hindering acceptance among veterinarians and horse owners.

This incompatibility between chips and scanners, however, might soon be a hollow issue.

On March 7, the International Organization For Standardization (ISO) published its standards for the electronic identification (EID) components. Members of ISO voted overwhelmingly in favor of a standard for electronic identification of animals, stated a press release recently distributed by the ISO. From now on, countries and user organizations can make use of this technique to identify animals and, if the standardized technology is used, can rely on the fact that their animals can be uniquely identified all over the world.

Officials of the United States Department of Agriculture (USDA) and the American Association of Equine Practitioners (AAEP) are delighted over the publication of EID standards. It's all very exciting, said Tim Cordes, DVM, a USDA Senior Staff Veterinarian for Equine Diseases who worked with the AAEP on identification. The AAEP has been in support of electronic ID for a long time, he said, but incompatibility of technology among EID conponent manufacturers has been a problem. Cordes said endless infighting among U.S.-based EID vendors prompted the AAEP to take a wait-and-see attitude. However, now that the ISO standards are in place, Cordes is confident the AAEP will move forward in pursuing the possibility and promise of EID technology.

The ISO is a worldwide federation devoted to developing standards for goods and products with the view of facilitating the international exchange of goods and services. ISO standards contain technical specifications to ensure that materials, products, processes, and services are fit for their purposes. International standards make life simpler by increasing the reliability and effectiveness of the goods and services worldwide. About 100 countries participate in the development of standards, although adhering to the standards is voluntary.

"Just think how valuable it will be (to horse owners) in terms of managing regulatory, veterinary, trade, and international movement of the horse," said Cordes.

Technique and Technology

EID technology involves implanting a microchip, or transponder, into the ligamentum nuchae of a horse's neck. The chip is encapsulated in a biocompatible glass vial, and the chip and vial together are only about the size of a large grain of rice. Veterinarians implant the vial midway between the poll and withers, and about one inch below the crest on a horse's left side. A 12-gauge needle is used to implant the chip, and the procedure is painless with no, or minimal, complications.

Each microchip, or transponder, is encoded with a 10-digit, unalterable numeric code. When a radio frequency scanner, or reader, is passed over the implantation site, the microchip is activated and sends back its number to a display window on the reader. The readers are battery powered, portable, and most have computer/printer interface capabilities.

EID manufacturers have a two-year transition period to alter their equipment to come into ISO compliance, but not all manufacturers need a grace period. A transponder manufactured by Destron-Fearing already meets the new ISO standards, and the company has a new scanner that reads both old and new technologies.

Field trials for EID systems began in the United States in 1983. Today, about 100,000 microchips have been implanted in horses in this country, many by the state of Louisiana for monitoring equine infectious anemia (EIA). Other uses for EID include: the controlling and tracking of other equine infections and dieases; recordkeeping and tracking purebred genetics; tracking lost or stolen horses and confirming ownership; and helping preclude substitution and fraud in races, shows, and sales.

Most major breed associations, including the American Paint Horse Association and Appaloosa Horse Club, allow their members to use EID in addition to other breed registry requirements, i.e., blood-typing, tattooing, or DNA testing. To date, only the International Andalusian Horse Association requires EID to expedite health certificate verification in the transportation of their performance horses across the Canadian, United States, and Mexican borders.

As it stands today, at least three U.S. companies are marketing the microchips and scanners for horses: Electronic I.D. Inc., Ft. Worth, Texas, which markets a chip developed by Destron-Fearing; Avid, Norco, Calif., which manufactures and markets its own chip; and Minnesota-based InfoPet, which markets a chip developed by Trovan. While EID proponents say the technology is the future of identification, opponents claim EID is not all it is cracked up to be. Proponents claim that EID:

  • is a humane and unalterable alternative to branding or tattooing;
  • is useful for health certificate, Coggins verification, and EIA management;
  • is important for identifying equine athletes; is useful for identifying breeding stock and establishing genetic integrity;
  • allows for easy re-registration of horses with lost or destroyed registration papers;
  • does not disfigure the horse;
  • is compatible with other forms of ID such as tattoos, brands, or physical features;
  • is easy to use and inexpensive--$25 to $100 depending on your veterinarian and whether or not you purchase accessories, i.e., warning signs and/or a freeze brand denoting a horse is carrying EID.

EID opponents claim:

  • the various chips and scanners on the market are not interchangeable--EID manufacturers do not cooperate, thus there might be a duplication of numbers;
  • microchips can be implanted by anyone;
  • microchips are not permanent and can be removed;
  • no breed registration is needed to have a microchip implanted;
  • microchips can migrate in a horse's body;
  • the glass vial could break;
  • chips are not always readable;
  • infection at time of implantation is possible.

"This (EID) is a tremendous idea," claims Ralph Knowles, DVM, who was a member of the AAEP's former Horse Identification Committee and is a pioneer in EID research. "I have had 10 years of experience using it (EID), and there really haven't been any problems of consequence. It's invisible on the horse, and no more painful than a penicillin injection."

Formerly with the USDA, Knowles currently is acting as a consultant for Electronic ID. Amelita Donald, vice president of Electronic ID, claims her company has implanted more than three million animals with EID technology worldwide, including more than 50,000 horses. According to a brochure from the company, groups using or endorsing their technology include: the Louisiana Department of Agriculture, Bureau of Land Management, International Andalusian Association, Royal Canadian Mounted Police, Colorado State University, Italian Trotters Association, South African Stud Book, and Canadian Horse Breeders Association.

"ISO standards dictate how the chips are constructed and how many numbers need to be on them," Donald said. "The new readers will be able to read every microchip already in the field today, as well as maintain enough protocol to read other transponders that may be developed in the future."

Currently, if you pass a reader over an injection site with multiple chips, the reader might only pick up the number from one chip. When microchips are placed too close, the chips' radio frequencies can conflict and cancel out one number. ISO standards dictate that readers be able to read every transponder, no matter how close they are implanted.

While Donald, Knowles, and Cordes believe horse owners should be interested in the welfare of their horses, they concur that the concerns harbored by EID opponents are groundless. If EID companies adhere to ISO standards, the standards will eliminate duplicate numbering and technology incompatibility.

Call Your Veterinarian

To prevent just anyone implanting chips, EID manufacturers restrict the sales of transponders to veterinarians. In return, veterinarians are expected to scrutinize the identification of the horse being implanted and to keep accurate records of each implantation. Donald also claims chip numbers cannot be altered, and Knowles says the chip is very difficult to remove and would involve general anesthesia.

"The reason we chose the nuchal ligament as the implantation site is that it is very difficult to remove a chip from that area," Knowles said. "We knew that in the case of a high-profile Thoroughbred, there might be some motivation to remove a chip."

Although early testing revealed that chips can migrate, most transponder manufacturers have incorporated anti-migration technology into their chip design. Knowles said the anti-migration designs have been very effective in keeping transponders close to the original injection/implantation site. Knowles also added that it is impossible to change a chip's number once it is implanted in a horse. Numbers are laser-etched on the chip during the manufacturing process, and a reader only tells you what the number is. It is not capable of changing numbers. Donald claims that Destron-Fearing's system failure rate is less than 0.5% and is more often a reader failure than a chip failure.

Safe for Horses

Knowles, Donald, Cordes, and several studies researched for this article all concur that EID is safe for horses.

The transponders were found to be extremely biocompatible with the tissues of both adult horses and foals, stated a 1987 EID study where 69 horses were implanted with transponders. There were no clinical signs of inflammation at the implantation sites. The study, managed by Knowles, A. A. Gabel, DVM, MS, and Steven E. Weisbrode, VMD, PhD, also concluded that even if a vial is broken after being implanted, it poses no danger to a horse's health or fertility.

Lastly, the study stated that EID was superior to other forms of equine identification in that it was also tamper-proof and accurate. Those conducting the study noted that the speed and accuracy of identification using EID make it superior to other identification methods, such as reading lip tattoos or brands or comparing photographs with chestnuts.

Whatever minor concerns or complications EID might pose for horse and horseman, Cordes said the potential of EID far outweighs any negative aspects of the technology.

About the Author

Aleta Walther

Stay on top of the most recent Horse Health news with FREE weekly newsletters from TheHorse.com. Learn More