It's been so cold lately that high-tech ID tags have been falling off cows' ears, according to researchers from the Prairie Agricultural Machinery Institute, or PAMI, in Humboldt.

Ranchers use identification tags known as RFID, which means the tags use radio frequencies to transmit data. The tags, small round and yellow, are made by a number of different companies and have become a useful tracking tool.

In a news release issued Tuesday, PAMI officials said researchers have been studying the effect of extreme cold on tags as a follow up to concerns ranchers had about devices falling out of cows' ears.

"We recognize there is frustration among producers related to tag retention," Dr. Joy Agnew, one of the researchers, said. "We wanted to address it."

A PAMI team has been putting different RFID tags through a number of tests, involving cold temperatures.

skpic RFID tag

Researchers at the Prairie Agricultural Machinery Institute have been studying the effect of cold on RFID tags for cattle. (PAMI)

"We used an engineering approach to systematically test the mechanical strength of RFID tags to determine if all tags are the same, if some are weaker, or some are stronger," Agnew said.

The researchers discovered that all the devices met the basic strength requirements set out by the Canadian Cattle Identification Agency, but also learned that temperature has a noticeable effect on the tags.

“Inserting the tags in the cold and comparing their strength with warm-applied tags was something about the tags that we believe no one else has tested,” Agnew said. “The whole effect of temperature on tag retention was a question mark.”

The temperature the researchers used was -30 C.

“We found that if the tags were inserted cold, they were much weaker than those inserted at room temperature,” Agnew said. The tags were not only weaker, but harder to insert.

One conclusion is that producers should avoid tagging animals in extremely cold weather or do so with warm tags and a warm applicator.

PAMI said they will be continuing their research on RFID tags.