En español | The secret to staying young in mind and body may be just a purr, tail wag or chirp away. But with all the breeds of dogs and cats, not to mention birds, selecting the right species and the pet with the right temperament can be daunting.

See also: Here's a guide on small- and medium-sized birds.

I'm here to help. In my 30-plus years as a veterinarian, I've treated just about every kind of dog and cat you can imagine, from the tiniest Chihuahua to the tallest Great Dane and from the super-small Singapura to the mountain-size Maine Coon. And, I've interacted with all kinds of birds.

Choose a pet that complements your lifestyle. — Bertil Hertzberg/Nordic Photos/Aurora Photos

Whether you're 50, 60 or beyond, you're never too old to share your life with a pet and reap the countless healthy dividends they offer. Just ask Flo Frum, an on-the-go 87-year-old from Oceanside, Calif., who adopted a miniature Schnauzer puppy a few months after Frank, her husband of almost 60 years, died from lung cancer.

That was six years ago. Today, she hurls tennis balls down her hallway and plays friendly games of tug with her spirited dog, Buddy. She dishes up healthy meals for him and sports as many photos of Buddy in her house as she does of her great-grandchildren. Friends and family marvel at her energy and optimism and she quickly credits Buddy for her ageless outlook.

"The house was so lonesome without Frank and I couldn't stand the quiet, so I adopted Buddy, knowing full well that Schnauzers are yappers," Frum says. "I wanted a dog with spirit and spunk, but not one who would shed or be too big for me to handle."

I salute Flo for knowing how to pick a pet that complements her personality and lifestyle. That's the first step in successful adoption of a pet: know thyself. If you want a lap lounger, then mellow-tempered Cavalier King Charles Spaniels (nicknamed the Love Sponge) or quiet Persians are better bets than leaping Labrador retrievers or play-all-day Bengal cats.

Other essential tips in finding the right match include:

Be picky and patient. Most people invest more time in picking out their version of a Range Rover than they do in finding the right Rover. Pets, on average, outlast the life of two or three cars. Don't select a pet by looks alone. Take the time to know his habits, temperaments and health care needs.

Next: What type of pet can you afford? »