John McQuiston, Zootoo.com

TAMPA, Fla. -- Peter Shute understands that most people's daily routines don't include breathing on their cats.

Then again, most people don't have a cat that can test someone's blood sugar level by sniffing his breath.

"When I come home that's the first thing he does," said Shute, a diabetic and a registered nurse who says that a person's breath can tell a lot about his health.

The skills that Elijah, his 2-year-old orange tabby, developed might also reveal more about how animals adapt their behavior to domesticated lives, as well as other ways they can be used in human service.

Shute said Elijah checks his blood sugar "two or three times a day" and has become part of his medical regimen.

"I may not be stabbing my finger any more I may just have Elijah come up and tell me if I'm OK."

Shute's doctor probably won't recommend foregoing the blood tests most diabetics use to monitor their blood sugar but Elijah has shown he can detect either high or low levels of blood sugar in people before they show any obvious symptoms.

"This cat has not been trained," said Mark Wallace, DVM, the medical director at the Lakeland, Fla., SPCA, where Elijah wound up after a previous owner passed away.

That woman had diabetes and Wallace speculates that Elijah made a connection between odors on her breath and differences in her behavior.

Low blood sugar can cause diabetic ketoacidosis, a life-threatening situation first indicated by restlessness, drowsiness or difficulty waking up, which can lead to coma and death.

Although dogs are renowned for their sense of smell, "cats can smell very minute quantities," Wallace said, "even pheromones, which is just the particles or molecules in the air."

At some point, Elijah began purposefully sniffing his owner's breath, checking for either the excess or absence of the ketones that could portend blood sugar trouble. If the levels are normal, he does nothing. If there's a problem, he meows an alert.

Linda Liker found this out when she took Elijah home one night. The administrative assistant at the Lakeland SPCA is also diabetic. Her task was to test Elijah.

"He fussed uncontrollably the entire ride home with me," Liker said.

She thought he acted that way because he disliked riding in the car. To be sure, she tested her blood sugar.

"It was 195," Liker said of her blood sugar level, where 120 is considered the top of the normal range.

Elijah had passed his audition.

The shelter wanted to place Elijah with someone who would benefit from his talent.

A volunteer at the Lakeland SPCA was a co-worker of Shute's and thought Elijah would make a good match. When Shute met Elijah, the cat did what it does to every newcomer (even this reporter): Got his face as close to Peter's as he could and took deep breaths.

Shute knew instantly what was happening. "What this cat was doing was a physical assessment," he said.

Shute was diagnosed with diabetes about four years ago. The disease is new enough to him that he doesn't always recognize the early warning signs that his blood sugar is off.

"I know that if I run into trouble that he's going to do something."

Wallace said few cats have been trained to perform this service and that Elijah is the only one he's heard of who has taught himself.

He may have developed his skill as a means of self-preservation. If his caregiver couldn't wake up, she couldn't feed him. Coincidentally, his original owner also had sleep apnea and Elijah would also alert her if she had stopped breathing in her sleep.

Dogs are largely considered easier to train as service animals. An organization in California called Dogs4Diabetics formed in 2004 to train dogs to alert Type-1 diabetics to unsafe blood sugar levels.

Cats, if they can be trained, might prove more useful to people in frail health, because they require less care than dogs.

Training cats to perform this service might be more of a challenge than teaching dogs but Shute says it's worth the effort. Cats, he says, are "an untapped resource that we're not paying attention to."

"He's got a job," Shute said of Elijah. "He knows what he's doing and he does it."