MISSISSIPPI STATE -- Ownership has its benefits, especially for pets.

Unwanted pets and stray animals often end up dead beside the road, or suffer from sickness and disease, said Dr. Roger Wilbur, a veterinarian at Mississippi State University's College of Veterinary Medicine. Some of these had owners who no longer want them, while others are descendants of strays.

"Animals that are abandoned have to fend for themselves," Wilbur said. "They usually are susceptible to disease because they aren't cared for. Many die of starvation. Sometimes they become nuisances by joining a pack of other unwanted animals."

The problem of stray animals has several causes, but the biggest is owner irresponsibility, Wilbur said. Owners fail to spay or neuter their pets and end up with litters they don't know what to do with. Too often, owners dump these puppies and kittens.

"Owners need to spay and neuter their pets to prevent unwanted pregnancies," he said. "This can be done as early as six weeks, but most veterinarians recommend doing this at six months of age."

Neutering a male cat costs about $40 and $75 for dogs. Spaying a cat costs about $85 and about $100 for a female dog, with higher costs for those in heat or pregnant.

Spaying female dogs has the added benefit of preventing nearly all risk of developing breast tumors, Wilbur said. These are a problem with older dogs, but spaying before a dog comes in heat is more than 99 percent effective in preventing the tumors.

The second leading cause of people abandoning pets is the inappropriateness of the pet to the owner. Often owners get a young pet without considering its size and needs when it grows up. Also, situations in people's lives change as owners move or get divorced, and suddenly the pet is a liability.

People also dump pets because they can't control them.

"The owners haven't trained them or taken the pet for obedience classes," Wilbur said.

Once abandoned, stray animals face a tough life on the streets, often burdened by diseases and parasites. Non-vaccinated dogs can pick up distemper, parvovirus and rabies from infected strays. Strays can carry internal parasites such as hookworms, roundworms, whipworms and tapeworms, as well as fungal infections and external parasites like fleas and ticks.

Wilbur said if strays come in contact with other non-vaccinated animals, these diseases and parasites can be passed on. However, vaccinations and a good preventative program can protect pets from these problems.

If an owner no longer wants a pet, dumping the animal should never be an option, Wilbur said.

"The much better alternative is to take the pet to an animal shelter so it has a chance of being adopted or humanely euthanized," he said.

And when people are looking for a pet to own, the local animal shelter is a good place to start. Many nice cats and dogs, some purebred, end up in these places, all needing a new home where they are wanted.