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New Study Shows Potential Benefits Of Spaying/Neutering Dogs After Age 1

PITTSBURGH (KDKA) - Louie is now 12-years-old, but his owner, Barb Nicholson, says he is healthy as a horse.

"He has not had any health issues. He's been healthy his whole life. He's not even been medicated for anything," she said.

Like millions of dogs in America, the pug was neutered long before he was a year old. Even though he is well up in years, Nicholson says he shows no signs of slowing down.

"He walks 45 minutes a day. He has no problems. No health problems. I just got his checkup and he said, 'For 12 years old, he's great,'" she said.

Roberta Finney owns a Kangal, which is also known as an Anatolian shepherd. The giant Turkish breed is used to herd livestock. Her male Kangal is now 2 1/2 years old, and he already weighs 139 pounds.

His breeder advised the owners to wait a while before having him neutered.

"The breeder said I guess that they were growing too fast, and I guess that they need that hormone or whatever so they don't grow rapidly," Finney said.

There are very strong opinions within the veterinarian community as to when dogs should be spayed or neutered.

"This is one topic, you bring it up in a group of vets, and you say that you should be waiting -- you shouldn't be spaying or neutering the dogs, you will see anger in the crowd," Dr. Mike Hutchinson, of Animal General Hospital, said.

Which explains why a new study from the vet school at the University of California, Davis is causing such a stir.

UC Davis did a retro-active study on 1,000 German shepherds, 1,000 Labrador retrievers, and 1,000 golden retrievers.

All of the dogs had already died, but researchers had complete health histories on all 3,000 animals. They put each breed into two categories. One category as for dogs that had been spayed or neutered. The other was for dogs that were "intact" -- or animals that were never spayed or neutered.

Here's what their study found for German shepherds:

"Dogs that were neutered -- castrated or spayed under a year of age -- developed joint disorders that were four times more prevalent than dogs that weren't neutered under a year of age," says Hutchinson. "So, 400 percent more joint disorders, hip dysplasia, cranial cruciate ruptures, ACL tears, which is a problem because it is an athletic injury."

What about the golden retriever?

"It was three times more joint disorders if you neutered them (golden retrievers) under the age of one, and with Labradors, it was twice the incidents, two times," says Hutchinson.

Many dog owners like Nicholson can tell you exactly why their vet advised having their dog fixed early.

"When we originally went and got him, they were telling us it was health benefits," she said of her pug, Louie. "I think it was something to do with cancer, which he doesn't have anything."

Hutchinson says that has been the conventional wisdom for decades among veterinarians.

"If you castrate a male dog, they don't get testicular cancer. That's 50 percent fatal, very expensive to treat. If you spay a female, they are not going to get mammary gland tumors, 99.9 percent chance of not getting them, and they are not going to get an infected uterus or ovarian cancer or cervical cancer," Hutchinson says.

However, after seeing the research on these large breeds, Dr. Hutchinson changed his mind.

"My advice to you with a German shepherd, or a Labrador or a golden retriever is let's wait until after a year of age before we neuter them. If you are going to neuter them, let's wait until after a year of age," he says.

But, he says that is not the case for shelters because their primary concern is population control.

"Give them a lot of credit. It took euthanasia's from 4 to 5 million a year down to less than 2 million. That is huge, and that's by early neutering and spaying of all those dogs and cats," he says.

The study by UC Davis Veterinary School clearly has not convinced all vets to change their advice. In Dr. Hutchinson's practice at Animal General in Cranberry, there are four vets. Two have stayed with the old convention of spaying and neutering as soon as the puppy is sexually mature.

However, Dr. Mike and another vet in the practice tell their patients to be patient.

"I know that it is a retroactive study, but it's the beginning and that's how we all start on the ground floor and then we watch the science now going forward, and I am glad that discussion has been started," he says.

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