Wichita ? On any given day on the remote roads of Kansas, hundreds of tractor-trailers are hauling cattle across the state’s vast rangelands, headed for feedlots and slaughterhouses.

And in an era of mad cow disease and the threat of agroterrorism, federal agriculture regulators want to be able to locate within 48 hours — or sooner — the whereabouts of each of the nation’s 100 million-plus head of cattle.

Enter a Kansas proposal that would combine GPS, cellular and radio frequency technologies to track cattle as they are in transit. It is one of the ideas the U.S. Department of Agriculture is testing and one that could shape the nation’s emerging animal identification system.

“People were excited about the Kansas proposal,” said Amy Spillman, spokeswoman for the department’s Animal and Plant Health Inspection Service. “They wanted to integrate the ability to track cattle as it came on and off the trucks.”

The department is spending $11.6 million in 29 states to test various ideas, such as proposals from Wyoming and Idaho to expand on their existing branding methods of identifying cattle. Kansas was given $805,000 for its one-year test project on a transportation-based system, which could have broad applications in an industry that ships 90 million animals by truck annually.

Here’s how it works: As animals are loaded onto trucks, an onboard reader collects a time and date stamp, location information using GPS technology, and identification numbers for the site and each individual animal. The data is sent via cell phone to a database kept by Kansas animal health authorities.

If the cattle are loaded or unloaded in a remote location without cellular service — such as the vast rangelands of the state’s Flint Hills — the information is stored in the onboard computer and automatically transmitted as soon as the truck passes a cell phone tower.

The project is especially appropriate for Kansas, known as the “black hole of the beef industry” because of the state’s dominance in the slaughterhouse and feedlot industries, said Dale Blasi, a Kansas State University researcher working on the project.

“Kansas has this unique issue of cattle coming in from everywhere,” he said. “We are not an export state like Nevada or a cow-calf state like Montana.”

On any given day in Kansas, between 400 and 500 trucks are on the road hauling cattle, said Mark Spire, a Kansas State University professor and project researcher. On average, cattle are shipped four times in their lives.

The state has only 1.5 million head of brood cows, but feeds 6 million cattle and slaughters 7 million head of cattle each year, he said. About 5.1 million cattle are shipped into Kansas from elsewhere in the nation.

“Within 24 hours from either coast, we can have cattle that can arrive in Kansas,” Spire said. “What that means is that Kansas is a state at risk for the introduction of potential animal diseases.”

The system was built by two companies — Osborne Industries in Kansas and Digital Angel Corp. of Minnesota — to the specifications of researchers at Kansas State University, said George Teagarden, Kansas Animal Health Commissioner.

Testing already has begun, and by March, researchers hope to begin installing $8,000 readers on 30 trucks hauling livestock from participating ranchers to plants operated by Kansas City, Mo.-based U.S. Premium Beef, the nation’s fourth largest meatpacking company. About 40,000 cattle will be tagged during the pilot program.

One advantage of the transportation-based system is that it doesn’t add to the workload of ranchers. The project’s developers feared individual readers — which would be used only once or twice a year — would end up at the bottom of the farmer’s toolbox, left out in the weather or where rats could eat its wiring.

“It takes that expense — that trial and tribulation — off the producer and puts it on truck drivers where we have a better opportunity to train,” Spire said.

There are other concerns about a national animal ID system, especially from ranchers worried about the security of the information, as well as adopting technology that either doesn’t work or becomes outdated quickly, said Doran Junek, a Cuba rancher and executive director of the Kansas Cattlemen’s Assn.

“We need to proceed with caution,” Junek said.

Lindsborg rancher Tom Toll sent in his site registration form and began placing electronic tags on his cattle this week.

“We need to get as many people using the tags and using the readers as we can, so we know the system works,” said Toll, president of the Kansas Livestock Assn.