TULSA, Okla. - After growing up on a cattle ranch, John Hassell became an electrical engineer specializing in wireless technology. So he feels doubly qualified to offer this warning about the system taking shape to track cattle across America: It won't work.

To be sure, he doesn't quibble with the logic of the system. It stems from the Bush administration's plan to give agriculture inspectors the ability to pinpoint the origins of mad cow and other diseases within 48 hours. Livestock facilities and individual animals will get identifying numbers, which owners will use to document the beasts' movements in industry databases.

The system isn't expected to be fully online until 2009, but already it's clear that in the sprawling U.S. beef and dairy industries — home to 100 million cattle — many producers will automate data gathering with radio-frequency chips attached to cattle ears.

And that's what has Hassell worried. He contends most of the radio-frequency chips making their way onto cattle ears are a terrible fit.

Those chips — based on the same radio-frequency identification (RFID) technology being integrated for inventory control by large retailers such as Wal-Mart Stores Inc. — are known as "passive" tags that broadcast identifying numbers for only a short range, generally just a few feet.

While cattle may be considered docile creatures, they are a lot more mobile and skittish than cases and pallets in Wal-Mart warehouses. Hassell believes only "active" tags, which broadcast identification data for up to 300 feet, will consistently work for the multiple owners and many environments that cattle pass through, from pastures to stockyards, feed lots and slaughterhouses.

Hassell is so convinced that he's launched his own company, ZigBeef Inc., to sell long-range tags. The name is a play on the "ZigBee" wireless standard employed by his tags.

"I really don't think ... on a mass scale that short-range, passive devices are going to be practical," he said. "The Betamax of the industry is the short-range tags."

That makes Hassell sound like many other startup technologists — pooh-poohing a rival standard at the expense of his own. But something makes this situation a bit unusual: Even beef producers who are using the passive flavor of RFID don't seem thrilled with it either.

The Joplin Regional Stockyards in Carthage, Mo., began using passive RFID to identify some cattle in 2001. But co-owner Steve Owens believes the technology "hinders the speed of commerce."

That's because the thousands of cattle that go through his facility wouldn't always naturally line up and orderly proceed past devices that can read electronic ID tags at short range. Most often, cattle quickly move through his yard in groups.

And if a cow has lost a tag or comes to him without one, "you've got to catch that animal in a head chute and hold it still so you can put the tag in an ear," he said. That can take 30 seconds each — which adds up when you've got thousands of mooing creatures to deal with.

These factors are big because human contact and other stresses can hurt a cow's ability to gain or maintain weight. That's costly because beef is, after all, sold by the pound — and generally with slim profit margins.

"I'm sure hoping and open to other technologies that might be able to solve some of our problems," Owens said.

Even so, he and other people in the industry figure that passive tags will carry the day.

For one thing, passive tags are cheaper, about $2 each versus roughly $10. Passive tags don't require batteries, because they get their power by induction from the electromagnetic energy sent by the reader.

And perhaps most importantly, most of the estimated 5 percent of cattle owners who are using RFID have passive tags. Changing that would be hard, since it's important for all players along the complex chain of cattle ownership to be on the same technical page.

"Despite its warts, I think (passive tagging) is the technology that's going to be brought to play initially," said Dale Blasi, a Kansas State University professor researching the challenges of RFID in cattle. "We're innovative, we'll learn how to work around these issues."

Still, Hassell holds out hope for ZigBeef. While he's not the first to suggest active tags for livestock, he's encouraged that the U.S.

Department of Agriculture has funded the company with an $80,000 grant. Soon he will be eligible for a $300,000-plus extension.

That makes this a crucial year. He has to attract potential customers while still fine-tuning his system. Part of his pitch is that while active tags cost more, their readers can run as low as $50, instead of hundreds or even thousands of dollars for passive RFID. The active readers' range could be dialed up or down to register multiple cows or just one at a time.

Hassell says his tags' batteries can last five to seven years, well beyond the 15-month life of typical beef cattle. And he asserts that most of the cost of the tags comes from their plastic housing, not their circuitry — so ZigBeef tags could easily include both passive and active chips, soothing producers' fears about choosing the wrong technology.

There are still other methods for recording that an animal crossed a certain link in the food chain, including retinal scans for identifying cattle. And there are a spate of old-school record-keeping practices, which often rely on brands, veterinary papers or visually spotting numbers on plastic ear tags and writing them down.

Many producers would love to stay that course, fearing the added cost of more detailed tracking. Some also fear that new databases would reveal private business information to rivals, regulators or animal-rights activists.

Meanwhile, pork and poultry producers tend not to have such worries. Pigs are unlikely to need RFID because the nation's 60 million hogs generally remain in large, easily identifiable lots, said Bobby Acord, a former USDA administrator who chairs the Swine Identification Implementation Task Force. Chickens follow a similar pattern — and are too numerous to tally individually, anyway, with 9 billion in the U.S. alone.

Early adopters of RFID in cattle have done so largely to better track sick animals and to document organic, grass-fed or other high-value beef and dairy. But holdouts note that premiums for RFID-equipped cattle would likely vanish as more cows get the tags.

Because of such hesitation, the cattle industry widely expects that the database system — which is technically voluntary for now — will become mandatory to ensure widespread participation.

Once that happens, old methods simply could become too difficult, said Allen Bright, animal ID coordinator for the National Cattlemen's Beef Association. For example, he notes that people are prone to error as they write down ear-tag numbers. It's not exactly easy in auctions teeming with 10,000 head of cattle.

"Just from a practicality standpoint, you need to automate those tags," said Bright, who owns a feed lot in Nebraska.

Kevin McGrath, chief executive of Digital Angel Corp., which has sold 6 million passive RFID tags for livestock in North America, contends that the U.S. beef industry has lost more than $3 billion because Japan and other Asian markets have been closed since the nation's first mad cow scare in 2003. If an automated ID system can persuade officials in those markets to resume accepting American beef, the technology would more than pay for itself, he argues.

Even so, McGrath says he understands the skepticism. Consequently, Digital Angel plans to test other tag frequencies in hopes of making the chips easier to read on moving animals.

"I think we still have to convince the industry that this is the right solution," McGrath said. When it was suggested to him that cattle RFID seems an experiment in progress, he agreed. "And it will be for a long period of time."