Rich Landers: Washington State vet helps bird dog owners get over hump on neutering

To neuter or not to neuter? Our family has pondered this decision six times and it still sinks my wife into a bog of anxiety, at least in the case of our dogs.

When it came to me, her decision was swift.

Meredith even insisted on cheerfully observing my vasectomy. She asked the urologist so many questions during the procedure I finally had to wave my hand and point out that I was getting less enthused about sacrificing my body for her medical curiosity as the local anesthetic began wearing off.

She’s more sensitive about our dogs.

Ten years ago, she devoted weeks to phone calls and research before conceding to neuter our English setter pup, Scout.

After finally getting the courage to drop off the pup with the veterinarian for surgery, Meredith drove all the way home only to make a U-turn in the driveway and speed back to race Scout out of the clinic before anything happened.

“I had second thoughts,” she said when she called to let me know we’d probably need another few days of deliberation on castration.

But while we were on the phone, Scout latched onto the neighbor child and started humping her leg. Decision made. When I got home from work that night, the pup was wearing the cone of shame to prevent him from licking the stitches.

Veterinary science has advanced in the past decade, but instead of making the decision easier on neutering our latest dog – a male Brittany named Ranger – we had to go through yet another whirlwind of research.

The question wasn’t whether or not to neuter, but rather at what age? We talked to several veterinarians and got different ideas ranging from 8 to 18 months.

While Meredith would stay up late pulling more opinions off the Internet and Ranger bullied the two older dogs in the house, I sought another level of help.

My effort culminated by landing an interview with Dr. Harmon Rogers at the Washington State University School of Veterinary Medicine. Rogers has been monitoring the evolution of neutering recommendations through 43 years of practice.

“I’ve seen the pendulum swing,” he said, “and in the last several years there’s been renewed interest in the timing of surgical sterilization for spaying and castration.”

Decades ago, it was pretty cut and dried, he said. Get the dog neutered when it was fairly mature but before it had a chance to produce puppies.

“At that time, there was the very valid concern about animal overpopulation and the number of unrestrained animals,” he said. “Early spay and neuter became the norm.

“Now we’ve had time to look at the impact of that direction and, as it is with a lot of things in health care, we’re seeing things to wonder about.

With more than six million unwanted dogs euthanized in shelters every year, there’s hesitation to back off the practice of early neutering, he said. “We don’t totally want to dismiss that concept. But by the same token, we’re still learning about the consequences.”

The discussion centers around hormonal regulation and stimulus.

“There are hormones produced by the body in an intact animal that tell the body that it’s time to start reproductive cycling and developing reproducing organs like ovaries and testes to produce eggs and sperm,” he explained.

Further research indicates that hormones and neurohormones also are involved in stimulus and feedback between the hypothalamus and elsewhere in the body.

Surgical sterilization can interfere with the signals. One part of the body may be waiting for the gonads to do their job. The pituitary responds by sending out hormones to get the gonads off their butts, but they’re not slacking – they’ve been removed.

Maybe the receptors in other body parts are reacting to the pituitary stimulation meant for the missing gonads. Are other tissues impacted?

“We don’t know,” Rogers said, noting that scientists currently are looking at possible impacts of early neutering to cartilage and tendons that might be causing orthopedic problems. Research also is exploring at potential issues with tissues in the thyroid gland.

“We do know that the growth of bones is affected by the presence of estrogen,” which is produced by the gonads of both male and female dogs, he said.

Removing the gonads eliminates the signal to the growth plates to continue progress in the long bones. Scientists have found some indications that bones of animals spayed or neutered in early ages grow to different lengths. The animals may grow a little taller. Research is looking into whether this impacts the angles of joints or stresses in ligaments or other things that could increase injuries, Rogers said.

“It seems like we’re seeing more CCL and ACL injuries in dogs in the last decade,” he said, but the evidence suggesting they’re the result of changes in long bone growth is inconclusive, so far.

Meanwhile, the possibility is influencing the recommendations. More vets are saying dogs should be given time to produce more estrogen to send signals to growth plates so their bones develop normally.

“You’re getting mixed messages from (veterinarians) because there are mixed messages in the research,” Rogers said.

Other studies suggest differences in the presence of disease in dogs that have been neutered at an early age. The instances can be increased or decreased.

A female has a reduced risk of mammary cancer, an important health consideration. That reduction in risk is greatest if spayed before first heat cycle, and there’s some value if done before the second with diminishing benefits after that, Rogers said.

Early neutering may increase the occurrence of some diseases, such as an increase in prostate cancer in male dogs. “But you have to look at relative risk,” Rogers said.

“Prostate cancer is rare in dogs. Doubling of the increase in risk of something that almost never happens still isn’t much of a risk. It’s like doubling the chance of winning the big lottery – your chances of winning are still unlikely.”

Benefits of neutering a male dog surgically include prevention of testicular diseases as well as rendering it less likely to wander, less prone to marking territory, less likely to get in fights while searching for females, less likely to hump the neighbor kid’s leg.

Spaying a female dog will prevent unwanted pregnancy, reduce risk of developing mammary tumors, and eliminate future treatment for a range of reproductive tract issues such as ovarian or uterine cancers, vaginal prolapses or inflammatory disease of the female plumbing.

But surgery is surgery with inherent risk in anesthesia and post-op bleeding.

“The problems are complex and nobody has all the answers,” Rogers said.

“The general consensus, which changes over time, is that if the dog is well controlled and the likelihood of it being bred without intent is low, it’s probably best to wait in the case of a female until after the first heat cycle but before the second cycle.”

For males, he said, wait until they reach near skeletal maturity before castrating. “About 12 months for a Brittany,” he said.

The new frontier of treatment, which is underway in some countries such as New Zealand, involves suppressing reproduction with implants that deliver drugs that are in the same category as the neurohormones produced by the hypothalamus. “They appear to keep a dog from reproducing while allowing growth plates to close,” Rogers said.

“Smaller dogs reach puberty and the growth plates close earlier than they do in larger dogs. A Great Pyrenees’ growth plates might normally continue to function until it’s almost 2 years old. A toy poodle’s might close by 8 months of age.”

Based on the science as it is today, and the position of the veterinary pendulum, Ranger got an extra few months for his growth plates to close.

But the bottom line for Ranger was the same as it’s been for Sage, Radar, Dickens and Scout before him.

And my wife is able to sleep through the night confident that she’s applied cutting edge science to all of her “boys.”