[Photo] Rats are highly intelligent animals, have been amazingly beneficial in medicine and can be very affectionate pets. (Credit: iStockphoto/Oleg Kozlov)

ScienceDaily (Jan. 24, 2008) ??? It’s the Chinese Year of the Rat, and if there’s ever been an animal that needed a total image makeover, it’s the rat.

Many people loathe rats and associate them with disease and filth ??? hardly a four-star recommendation for the furry creatures. But the truth is, they are highly intelligent animals, have been amazingly beneficial in medicine and can be very affectionate pets, says a Texas A&M University veterinarian and rat expert.

Dr. Kristina Kalivoda, a small animal instructor in the College of Veterinary Medicine & Biomedical Sciences, believes rats are among the most misunderstood of all animals and are not the horror from the sewer people tend to think they are.

“Rats are very smart and are known for their problem-solving skills,” says Kalivoda, an admitted rat fan.

“Many people believe they are nasty, filthy creatures, and that’s not true at all. In fact, rats wash themselves several times a day, about as often as most cats.”

The name itself poses a rat problem.

Rats are rodents, and rodent comes from the Latin word meaning “to gnaw.” Rats do like to chew and they are constantly searching for food. They tend to live where humans live for two reasons ??? food and shelter.

They have been parodied by Hollywood ??? who can forget James Cagney’s immortal line, “You dirty rat!” ??? while last year’s hit film Ratatouille showed the humorous side of the creatures, and Disney’s Mickey Mouse has been appealing for decades, as have Tom and Jerry.

Comedian David Letterman often jokes about New York City’s countless rats, bragging that “our rats can whip your honor students.”

Some rat facts include:

Their lifespan is between 1-3 years;
They have no gallbladder;
Rats have a bellybutton;
Rats can’t vomit;
They are prolific breeders: A pair of rats can produce 15,000 descendants in their lifetime, and female rats spend almost their entire lives pregnant;
Rat teeth are incredibly strong and can chew through walls, plumbing and even concrete.
Rats come in different colors such as silver, blond, grey, black and albino. Some have short ears and some have floppy ears;
The largest rat, the African rat, can be 3 feet in length ??? about the size of a small dog;
Rats are expert swimmers;
Rats can laugh and do so with a high chirping sound when amused.
“Rats are very smart and they can figure out things quickly,” Kalivoda adds. “If you put them in a maze, they can find their way out in no time at all. They are social creatures and can be very affectionate. They are also easily trained and many can do tricks.”

The difference between a rat and a mouse, Kalivoda explains, is size. Rats are much larger than mice, often three to four times as large, and mice don’t live as long as rats.

Despite their frisky mannerisms, many rats have internal health issues, mainly cancerous tumors. Kalivoda says rats often develop mammary tumors or other cancers, and rats also frequently suffer from respiratory illnesses.

But their benefits in medicine have been phenomenal. In research laboratories around the world, rats have contributed to more cures than any other animal, and in that regard, have no doubt saved millions of lives.

“In my opinion, rats do a get a bad rap,” Kalivoda believes.

“I can tell you firsthand that rats can make great, fun pets. A lot of people have rats as pets, and they will tell you they’re the best pets they’ve ever had.”

Adapted from materials provided by Texas A&M University.