QUEENSTOWN -- For a pair of 2-year-olds who seem to regard chasing each other's tail as a life's calling, Prudence and Perry can snap to attention with remarkable speed.
That's because Prudence, a black Labrador retriever, and Perry, a German shepherd, have been trained to set aside their natural insouciance at the drop of a command from either Cindy Rochen or her husband, Tim Bunge.
For Mr. Bunge and Ms. Rochen, who are both partially disabled, the quick obedience of their dogs can mean the difference between standing and falling.
Prudence and Perry are pets, for sure. But they're also utility dogs specially trained to assist masters with mobility limitations.
Once associated mainly with seeing- and hearing-impaired individuals, canny canines like Prudence and Perry these days are providing a degree of independence for many people who simply have a tough time getting around.
Called companion dogs, service dogs or walker dogs, the animals can help people perform a variety of functions crucial to everyday life.
In addition to picking up dropped objects and putting them within reach of their masters, Prudence and Perry can act as braces to steady a wobbly walk or help the Queen Anne's County couple get out of their chairs. Outfitted with custom-made backpacks, the dogs also carry items for their owners.
For others with greater physical handicaps, dogs can be trained to pull wheelchairs, open doors, turn on light switches and pick up telephone receivers.
Under the federal Americans with Disabilities Act and a 1990 Maryland law, handicapped individuals with registered service dogs have access rights to all public places.
Making the public aware of the rights of disabled individuals, particularly those with service dogs, is a never ending task, said Lisa B. Williams, executive assistant for the state Governor's Office for Individuals with Disabilities.
"I think all of us are used to seeing a blind person with a dog," she said. "It's more difficult to understand why, if a person is not blind or not in a wheelchair, they would need a dog."
In addition to providing Mr. Bunge and Ms. Rochen with increased mobility, service dogs offer them a degree of protection.
Handicapped people often fall prey to crime, said Mr. Bunge, who credited Perry with chasing away three men who threatened to stab and rob him last month in Salisbury.
Mr. Bunge and Ms. Rochen used their own dog-training experience when teaching Prudence and Perry. But most disabled individuals in the United States who want a service dog rely upon about 10 reputable training groups.
The demand for service dogs is increasing more rapidly than the animals can be trained, according to a spokesman for Canine Companions for Independence, the oldest and largest service dog training organization in the country.
The 17-year-old organization based in Santa Rosa, Calif., has five regional offices and a waiting list of 600 people, said Charlie Creasey, associate director of development.
In CCI's northeast region alone, which covers Maine to West Virginia, more than 100 people have filed applications for dogs. Regional director Paul Mundell said it may take more than four years to provide the dogs because the training period is both grueling and expensive.
Dogs are trained to perform 60 commands and are expected to "graduate" at age 2. When a dog is paired with a potential master, the two undergo a three-week school before they are allowed to return home.
Training the dogs can cost between $5,000 and $10,000. Many organizations rely upon donations. Fees charged to the handicapped vary greatly, and some groups retain ownership of the dog even after it is paired with its master.
Mr. Creasey said CCI prefers to use golden retrievers and Labradors because they are intelligent, strong and eager to please their masters.
And because the dogs are known to be friendly, they serve as "ice-breakers" for handicapped individuals in social settings.
At the Bunge-Rochen household, the relationship between dog and human has gone beyond a casual master-servant arrangement.
"We train them to serve us and, in return, we care for them and love them," said Ms. Rochen.
Ms. Rochen, 34, injured her spine in a car accident 10 years ago. In 1988 she was involved in two other automobile mishaps -- once when she was forced off the road while she was driving to her physical therapy session -- that further damaged her back.
She later met and married Mr. Bunge, a farmer who could bench-press 400 pounds. When she had trouble walking or getting out of bed, she turned to him for help.
But two years ago Mr. Bunge, 36, was left with two herniated spinal disks when a tractor he was driving jackknifed on a Carroll County farm where he worked.
The couple acquired Prudence first and soon after bought Perry from a Delaware breeder. They said they now want to launch their own dog-training service and are looking for property to locate a business, which Ms. Rochen said is likely to begin slowly on a non-profit basis.
Looking back on their predicament during the pre-Prudence and Perry days, Ms. Rochen remarked: "You got to either think it was some great cosmic joke or there is a God and He had plans."