Early Spay-Neuter Considerations for the Canine Athlete
courtesy of Canine Sports Productions
A study by Salmeri et al in 1991 found that bitches spayed at 7 weeks grew significantly taller than those spayed at 7 months, and that those spayed at 7 months had significantly delayed closure of the growth plates than those not spayed (or presumably spayed after the growth plates had closed). A study of 1444 Golden Retrievers performed in 1998 and 1999 also found bitches and dogs spayed and neutered at less than a year of age were significantly taller than those spayed or neutered at more than a year of age. The sex hormones promote the closure of the growth plates, so the bones of dogs or bitches neutered or spayed before puberty continue to grow. Dogs that have been spayed or neutered well before puberty can frequently be identified by their longer limbs, lighter bone structure, narrow chests and narrow skulls.
This abnormal growth frequently results in significant alterations in body proportions and particularly the lengths (and therefore weights) of certain bones relative to others. For example, if the femur has achieved its genetically determined normal length at 8 months when a dog gets spayed or neutered, but the tibia, which normally stops growing at 12 to 14 months of age continues to grow, then an abnormal angle may develop at the stifle. In addition, with the extra growth, the lower leg below the stifle becomes heavier (because it is longer), causing increased stresses on the cranial cruciate ligament. These structural alterations may be the reason why at least one recent study has shown that spayed and neutered dogs have a higher incidence of CCL rupture. Another recent study showed that dogs spayed or neutered before 5 1/2 months had a significantly higher incidence of hip dysplasia than those spayed or neutered after 5 1/2 months of age. Breeders of purebred dogs should be concerned about these two studies and particularly the latter, because they might make incorrect breeding decisions if they consider the hip status of pups they bred that were spayed or neutered early.
There is a slightly increased risk of mammary cancer if a female dog has one heat cycle. But my experience indicates that fewer canine athletes develop mammary cancer as compared to those that damage their cranial cruciate ligaments. In addition, only about 30 % of mammary cancers are malignant and, as in humans, when caught and surgically removed early the prognosis is very good. Since canine athletes are handled frequently and generally receive prompt veterinary care, mammary cancer is not quite the specter it has been in the past. A retrospective study of cardiac tumors in dogs showed that there was a 5 times greater risk of hemangiosarcoma, one of the three most common cancers in dogs, in spayed bitches than intact bitches and a 2.4 times greater risk of hemangiosarcoma in neutered dogs as compared to intact males. A study of 3218 dogs demonstrated that dogs that were neutered before a year of age had a significantly increased chance of developing bone cancer, a cancer that is much more life-threatening than mammary cancer, and that affects both genders. A separate study showed that neutered dogs had a two-fold higher risk of developing bone cancer. Despite the common belief that neutering dogs helps prevent prostate cancer, at least one study suggests that neutering provides no benefit.
The study that identified a higher incidence of cranial cruciate ligament rupture in spayed or neutered dogs also identified an increased incidence of sexual behaviors in males and females that were neutered early. Further, the study that identified a higher incidence of hip dysplasia in dogs neutered or spayed before 5 1/2 months also showed that early age gonadectomy was associated with an increased incidence of noise phobias and undesirable sexual behaviors. A recent report of the American Kennel Club Canine Health Foundation reported significantly more behavioral problems in spayed and neutered bitches and dogs. The most commonly observed behavioral problem in spayed females was fearful behavior and the most common problem in males was aggression. Yet another study showed that unneutered males were significantly less likely than neutered males to suffer cognitive impairment when they were older. Females were not evaluated in that study.
Other Health Considerations
A number of studies have shown that there is an increase in the incidence of female urinary incontinence in dogs spayed early. Interestingly, neutering also has been associated with an increased likelihood of urethral sphincter incontinence in males. This problem is an inconvenience, and not usually life-threatening, but nonetheless one that requires the dog to be medicated for life. A health survey of several thousand Golden Retrievers showed that spayed or neutered dogs were more likely to develop hypothyroidism. This study is consistent with the results of another study in which neutering and spaying was determined to be the most significant gender-associated risk factor for development of hypothyroidism. Infectious diseases were more common in dogs that were spayed or neutered at 24 weeks or less as opposed to those undergoing gonadectomy at more than 24 weeks. Finally, the AKC-CHF report demonstrated a higher incidence of adverse reactions to vaccines in neutered dogs as compared to intact.
For these reasons, I have significant concerns with spaying or neutering dogs before puberty, particularly for the canine athlete. And frankly, if something were healthier for the canine athlete, would we not also want that for pet dogs as well? But of course, there is the pet overpopulation problem. How can we prevent the production of unwanted dogs while still leaving the gonads to produce the hormones that are so important to canine growth and development? The answer is to perform vasectomies in males and tubal ligation in females, to be followed after maturity by ovariohysterectomy in females to prevent mammary cancer and pyometra. One possible disadvantage is that vasectomy does not prevent some unwanted behaviors associated with males such as marking and humping. On the other hand, it has been my experience that females and neutered males actively participate in these behaviors too. Really, training is the best solution for these issues. Another possible disadvantage is finding a veterinarian who is experienced in performing these procedures. Nonetheless, some do, and if the procedures were in greater demand, more veterinarians would learn them.
I believe it is important that we assess each situation individually. If a pet dog is going to live with an intelligent, well-informed family that understands the problem of pet overpopulation and can be trusted to keep the dog under their control at all times and to not breed it, I do not recommend spaying or neutering before 14 months of age. In the case of dogs that might be going to less vigilant families, vasectomy and tubal ligation will allow proper growth while preventing unwanted pregnancies.
RETHINKING SPAY & NEUTER
By Geneva Coats R.N., TheDogPlace.org Genetics Editor
Is pet sterilization a purely beneficial routine procedure? Most breeders today sell companion puppies under contracts requiring spay or neuter as a condition of sale. Ingrained in current culture is the notion of pet overpopulation and to prevent the deaths of animals in shelters all pets should be sterilized. To bolster that campaign, we are told that a sterilized pet is happier, healthier and longer-lived than one who remains intact. What are the facts?
In the mid-twentieth century, there was an abundance of pets; many were available “free to good home” via newspaper ads. Few pets were sterilized, and many people unwisely allowed their dogs to roam the neighborhood, producing unplanned litters.
According to “Maddie’s Fund” president Richard Avanzino, in the 1970s, our country’s animal control agencies were killing, on average, about 115 dogs and cats annually for every 1000 human residents. This amounted to about 24 million shelter deaths every year. Avanzino is also the former executive director of the San Francisco SPCA, and is regarded by many as the founder of the modern no-kill movement in the US.
"The Problem" of too many pets and not enough homes to go around began a huge campaign based on spaying and neutering pets. Vets began to routinely urge clients to sterilize their pets as an integral part of being a “responsible owner”. Planned breeding became a politically incorrect activity. A popular slogan today is “Don’t breed or buy, while shelter dogs die.”
The crusade for spaying and neutering pets has been very successful. A 2009-2010 national pet owners’ survey by the American Pet Products Manufacturers Association reveals that the vast majority of owned pets...75% of dogs and 87% of cats... are spayed or neutered. (As reported by the HSUS in Dec. 2009):
In recent years, according to Avanzino, annual shelter death numbers have dramatically declined to about 12 per thousand human residents, or about 3.6 million deaths each year. This amounts to a staggering 85% reduction in killing since the 1970s. We have reached a nationwide pet shelter death rate averaging just 1.2% per population, effectively a “no kill” rate.
Feral cats and kittens account for the majority of shelter numbers but many areas have actual shortages of adoptable dogs, particularly purebreds and puppies, and must import from other regions to fill the need. Dogs are being smuggled into the US by the thousands with rescue groups importing small dogs from Mexico, Brazil, the Caribbean, Taiwan and Romania, to name some of the most popular points of origin. The conservative estimate is that 300,000 dogs are imported into the US each year to meet the demand for pets.
According to shelter expert Nathan Winograd, every year in this country, approximately 3 million adoptable pets die in shelters.* At the same time, around 17 million US households are looking for a new pet. That is 17 million households above and beyond those who already will adopt a shelter or rescue pet. There are nearly six times as many homes opening up every year as the number of adoptable pets killed in shelters! It seems the greatest challenge these days is to find ways to match up the adoptable pets with the homes that are waiting for them. Breed rescues fill this niche admirably, but are privately funded and desperately in need of assistance in order to be able to effectively perform this service. Perhaps some of the public funds budgeted for shelters to kill animals could be better spent helping rescue groups who are proactive in matching adoptable pets to suitable homes.
SPAY/NEUTER AND HEALTH
Now that we have addressed the issue of pet overpopulation, let’s examine the claim that sterilization surgery promotes better health. While there are some benefits to sterilization, there are some drawbacks as well.
Sterilization will naturally serve to prevent any unwanted litters. In bitches, spaying will greatly reduce the risk of breast cancer, pyometra, perianal fistula and cancers of the reproductive organs.
Spay surgery itself carries a somewhat high rate (around 20%) of complications such as infection, hemorrhage and even death. Spaying significantly increases the rate of urinary incontinence in bitches….about 20-30% of all spayed bitches will eventually develop this problem. This is believed to be most likely caused by the lack of estrogen that results from being spayed.
Sterilization of males may reduce some unwanted sexual behaviors, but there are few other proven benefits to neutering a male dog. Testicular cancer is prevented, but the actual risk of that cancer is extremely low (<1%) among intact dogs. Contrary to popular belief, studies show that the risk of prostate cancer is actually HIGHER in neutered dogs than in their intact counterparts.
Several studies prove significant health risks associated with sterilization, particularly when done at an early age. The most problematic is a delayed closure of the bony growth plates. This results in an abnormal, “weedy” skeletal development that increases the incidence of orthopedic problems like hip dysplasia and patellar luxation. Working and performance dogs, if neutered before maturity, risk the inability to perform the jobs they were bred for.
But by far the most startling news to surface this year is the result of a study that shows that keeping ovaries to the age of six years or later is associated with a greater than 30% increase of lifespan in female Rottweilers. Similar studies in humans reinforce this finding.
A 30% longer lifespan means that you could have many additional years with your bitch simply by delaying spay surgery until middle-age or later.
Behavioral studies show that sterilization increases fearfulness, noise phobias and aggression. Other well-documented adverse health effects of de-sexing include increased risk of bone cancer, hemangiosarcoma, hypothyroidism, and cognitive dysfunction in older pets. Sterilization confers an increased susceptibility to infectious disease, and also a higher incidence of adverse reactions to vaccines.
So there is no need to feel obligated to sterilize for health or welfare reasons. But what about the need to protect the puppies that we sell from unethical breeders?
PUPPY SALES CONTRACTS
Many breeders are justifiably very concerned about their dogs being subjected to neglect or abuse by falling into disreputable hands. To help prevent such situations, it has become commonplace for breeders to include spay/neuter requirements in their pet sales contract, and/or to sell the dog on a limited registration. Another common stipulation, particularly for a show/breeding dog, is requiring that the dog be returned to the seller in the event the buyer no longer wishes to keep him.
Such contracts are highly effective when selling a puppy to someone who is honest and ethical. However, contracts are easily skirted by the unscrupulous, particularly if the buyer lives in a different region. Someone intent on breeding may do so regardless of contract language, and then sell the puppies without registration. And without personal knowledge of the living conditions at your puppy’s new home, it is impossible to predict what sort of care and attention he or she will receive. Even some show breeders may have very different ideas on what constitutes proper care. There is no substitute for a home check to follow up that initial puppy application!
Bottom line, the best insurance for your puppies is making sure that you get to know the buyer personally. If something about the buyer or his attitude doesn’t seem right, then it’s probably best to cancel the sale. If you want to sell puppies on spay-neuter agreements you might consider advising the buyer to wait until the puppy reaches maturity before having sterilization surgery performed. Another idea is to ask your vet if vasectomy would be a viable alternative to castration for your male. This would preserve sex hormones and possibly prevent some of the adverse health effects of castration.
Sterilization of all dogs sold as companions may have some unintended adverse effects. The nature of breeding for the show ring involves intense selection that severely narrows the gene pool in many, if not most, breeds. Some breeds started with just a small pool of founders. Through the years, overuse of only a few popular sires further reduced the genetic variety available in the breed. When troublesome health problems surface and become widespread, where can we turn for “new blood”?
The show-bred population of a breed may have become too small as a result of intense inbreeding or the genetic bottleneck created by overuse of popular sires; or the breed gene pool may have become genetically depleted because of unwise selection for specific, sometimes unhealthy physical traits favored in the show ring. As a result, dogs from the “pet” population may actually be the salvation of the breed gene pool.
Trying to guess which dogs are the "best" to keep intact for showing and breeding can be hit-or-miss. Imagine the scenario where a successful show dog eventually develops a heritable health issue, while his brother is much healthier...but brother was neutered long ago, thereby eliminating those good genes forever. What about that Champion's non-show quality sister, who has good health, great mothering instincts and the genetic ability produce exceptional offspring? If sold as a spayed companion, her genes are effectively lost.
And what about the very future of the dog fancy? Many people (myself included) bought an intact dog as a pet, and only later sparked an interest in showing and breeding. Developing new breeders is critical to the survival of our sport, but if we sell all companions on spay/neuter agreements, we will lose many fanciers before they have the chance to discover the joy of dog breeding and showing!
Sadly, mandatory sterilization laws are sweeping the nation and may further compromise the future of the dog fancy. AKC registrations continue to decline and the push to legally and/or contractually require spay and neuter of most every dog will only worsen that situation.
Regardless, there is a huge demand in society for healthy pets; a demand which the responsible breeders could not come close to meeting even if they wanted to...and sometimes, they do not want to. The choice we have as a society is how that demand will be filled. Many believe that only responsible people should be allowed to keep intact dogs and breed on a limited basis. However, the attempt to legally force well-regulated and inspected commercial breeders and the casual small home breeders out of the picture leaves only the unregulated, less visible "underground" producers and smugglers to fill the need for pets. Perhaps it is time to re-think our preconceived notions about who should and shouldn't possess intact dogs!
As a dog owner, one must weigh the risks of sterilization against the benefits in order to make that very personal decision. Popular culture and many veterinarians downplay or even ignore the risks involved with spay/neuter because of their own belief in the need to reduce dog breeding in general. Many people still believe that overpopulation remains a pressing concern and that sterilization always promotes better health. Some even believe that breeding a female is abusive. It seems the animal rights groups have done an excellent job of brainwashing the public on these matters!
As breeders, we may be wise to re-examine the routine request to have all our companion puppies spayed or neutered. The future availability of pets, the perpetuation of the dog fancy, the health of the individual dogs and the gene pools of the breeds that we love may all depend on keeping a few more dogs intact!