Ask the Vet
What to Know About New EID Rules for Cattle
READER QUESTION:
We sold some pairs recently, and our veterinarian said we had to have EID (electronic ID) tags in everything for the health certificate. We did not have to do this last year. When did this become required?
DR. MCMILLAN'S ANSWER:
There was a significant rule change by USDA that took effect Nov. 5, 2024. After this date, official ear tags for almost all cattle and bison must be both visually and electronically readable. The rule's goals, according to USDA, are "to enhance disease traceback, limit the spread of devastating diseases and provide information needed for foreign countries to recognize disease-free regions."
While some producers have concerns over this rule, I have long worried that we do not have a good animal disease traceability system anymore. At the peak of the brucellosis and tuberculosis eradication program, almost every cow had an official ID that traced back to the farm of origin: the old, reliable silver or orange metal tag.
The USDA rule applies to:
-- All sexually intact cattle and bison 18 months of age or older.
-- All dairy cattle.
-- Cattle and bison of any age used for rodeo or recreation events.
-- Cattle or bison of any age used for shows or exhibitions.
States may set stricter standards. Wisconsin, for example, requires official ID for all cattle and bison, except beef steers. Michigan has had electronic identification tag rules in place for several years.
The tags must:
-- Be approved by the USDA.
-- Meet quality and performance standards.
-- Be tamper proof.
-- Contain a unique ID.
-- Display the U.S. official ear tag shield.
The only tags that meet federal requirements are AIN (Animal Identification Number) ear tags, commonly known as "840" tags. AIN tags begin with the official country code ("840" for the U.S.) followed by 12 digits. With some of these tags, the EID part is the button back for the visual tag, but I prefer a visible tag and a separate EID button since the button is much less likely to be lost versus any visual tag.
Shearwell Data has a new EID tag like the old metal ear clips. The company says they will have excellent retention and electronic ID capabilities. I have never used these tags, but I am very interested in hearing from anyone who has experience -- either good or bad -- with them.
**
Editor's Note: Please contact your veterinarian with questions about the health of your herd or other animals. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice but is purely for informational purposes. Email Dr. Ken McMillan at vet@dtn.com.
(c) Copyright 2025 DTN, LLC. All rights reserved.
