One thing stood between a Southern New Mexico dairy farm and a financial catastrophe -- a brand.

But under a new proposed federal rule for tracing livestock shipped between states, the brand alone wouldn't have protected the farm, said state veterinarian Dave Fly. The animal disease traceability rule, as currently written, would remove brands from the official list of acceptable markers for tracking sick livestock. It would require beef cattle, dairy cattle and other livestock producers to use numbered ear tags or radio frequency devises.

New Mexico is one of 14 states where brands are the legal method for tracing animals from their birth places to slaughter or dairy farm.

The U.S. Department of Agriculture wants a national identification system in place to more efficiently identify sick animals, trace their movements and prevent the spread of diseases such as bovine tuberculosis. They argue that brands aren't sufficient because not all states use them.

Cattle might be happy to have the hot brand go away, but ranchers and dairy producers say they're still necessary. Brands are an iconic symbol of the old West dating back to the Spanish and the only sure-fire way to catch cattle rustlers.

The New Mexico Livestock Board traces the state's first hot brand to Don Juan de Oñate, who in 1598 brought along 7,000 branded cattle from Chihuahua, Mexico, to the Santa Fe area. More than 30,000 brands are now registered with the state.

New Mexico developed an animal identification system based on brands two decades before it was a state. Now it's one of the best animal traceability systems in the nation, Fly said. Livestock are inspected as they enter or leave New Mexico and as they travel between districts inside the state. All the data is computerized and in short order a livestock inspector can figure out where a cow or bison was born and where it was shipped, Fly said.

Brands regularly protect New Mexico producers from false accusations, Fly said. When federal inspectors claimed a dairy cow with tuberculosis was from a Southern New Mexico dairy, Fly's first question was did it have a brand. "It didn't. It had only an ear tag, and this cow had already been through three states," Fly said. "The dairy farmer could legally prove it wasn't his cow."

If he hadn't been able to, it would have cost the state $50,000 to test the 5,000 dairy cows at the farm for TB and cost the producer an equal amount in reduced milk production. "It's a big deal when you're a farm accused of having a diseased animal," Fly said.

The state ships more than 100,000 beef cattle out of state every year and imports about the same. Another 100,000 dairy cattle are moved in and out of the state. Some 360,000 head of cattle come across the New Mexico state line from Mexico and 300,000 of those are shipped to other states.

Fly said the feds shouldn't rely on ear tags alone because they can easily be cut off and replaced with other ear tags. A good brand can't be altered and it doesn't disappear.

Charlie Rogers, owner of the Clovis Livestock Market was on a national advisory group for the new rule. He said in one of the group's rare unanimous votes, they asked the U.S. Department of Agriculture to keep brands on the official animal identification list.

"I'm hoping we convinced them to leave brands as official IDs when agreed on by states and tribes," he said.

This is the USDA's second attempt at a national identification system. An effort launched in 2004 cost $120 million and after five years only a third of the country's livestock producers were participating.

The new version of the rule will give some flexibility to tribes and states to develop an animal identification system for interstate commerce. The proposed rule is limited to livestock shipped and sold between states. It does not apply to small-scale livestock producers and those keeping livestock in state.

Fly and Rogers agree a robust nationwide system for tracing livestock is necessary. It just can't rely on ear tags alone.

The final rule isn't expected for several months. For more information on proposed "animal traceability" rule, www.aphis.usda.gov/newsroom/2011/08/pdf/QAtraceabil.VS.pdf