Everyone seems to have an opinion when it comes to spaying and neutering
dogs. Some opinions are based on fact while others could not be further from the truth. How many times have you heard pet owners say, "I don't want to spay my bitch because she'll become fat and lazy." "I don't need
to spay/neuter my dog because there aren't any other dogs around." Recent scientific studies dispel most of these 'old wives tales'. Early neutering, prior to 5-7 months of age, has slowly developed over the past 20-30 years
to help alleviate the pet over-population problem, and may prove to be of further benefit to dog breeders.
Eliminating undesirable behavior is the most common reason for neutering male animals. Male specific activities such as
urine marking, mounting and intermale aggression are markedly reduced or eliminated in 50-60% of dogs as a result of neutering. Behavior patterns common in both males and females, such as watchdog barking, playfulness and attention
seeking are not affected by spaying or neutering. No basic personality or behavioral changes occur as a result of neutering ... except the less desirable male habits which may be eliminated or at least reduced. Male dogs that are
neutered before puberty usually will not develop undesirable behavior.
American Veterinary Medical Association supports the concept of early (8-16 weeks of age) ovariohysterectomies/gonadectomies in dogs and cats, in an effort to
stem the overpopulation problem in these species.
Having been taught that 6 to 7 months of age is the proper time to spay/neuter puppies, and having no information regarding the effects of early spay/neuter on the long-term
health of the animal, many veterinarians have been reluctant to advise their clients to have their pets spayed/neutered at 6 to 7 weeks of age. However, there is an accumulating body of evidence indicating that the positive results
quite possibly outweigh any remaining unknown risks.
Studies conducted on early spays and neuters puppies report that the anesthetic and surgical risk is minimal.One study comparing the effects of neutering puppies at 7 weeks to
those neutered at 7 months, found that neutering at either age produced similar effects on physical, skeletal and behavioral development. Neutering did NOT affect food intake or weight gain. Neutering did NOT result in inactivity
or lethargy, in fact, all neutered dogs were assessed by their caretakers to be more active than their sexually intact counterpart. They also found that prepuberal gonadectomy does NOT stunt growth; indeed, it contributes to growth
enhancement. Bone growth ceases when the physiological growth plates "close." This closure is delayed about one month with prepuberal neutering resulting in forelimb bones growing a fraction of an inch longer than those
of the un-neutered pups.
These studies report that anesthetizing 6- to 7-week-old puppies was uneventful. Spays are reported to be easier and faster at 6 to 7 weeks than at 6 to 7 months because there is little subcutaneous fat
to hinder entrance to the abdominal cavity and the lack of vasculature reduces hemorrhage. Finding organs was no harder than on the older animal. The speed of castrations at 6 to 7 weeks and at 6 to 7 months is the same, and the
testicles are easier to remove and break down. Finally, the younger animals recovered faster and with less pain.
Several of these studies addressed the question of long-term effects on the health of the animal by comparing, at
maturity, groups of animals neutered at 6 to 7 weeks and at 6 to 7 months.
Many aspects of skeletal dimensions, body weight and composition, physical maturation, secondary sex characteristics or behavioral development of dogs
neutered/spayed in the two groups were compared at one year of age. The only notable difference found was that the animals neutered at 6 to 7 weeks of age were more likely to have immature external genitalia at maturity; this has
no known clinical significance. The benefits of neutering are the same at either age: reduced risk of reproductive disorders and of mammary neoplasia.
Animal shelters, being closest to the tragedy of mass euthanasia, were first
to adopt early spay/neuter policies. Even though the majority of animal care and control facilities have a mandatory spay/neuter policy, typical compliance rates are from 50% to 60%, in spite of pre-adoption screening, spay/neuter
contracts, and follow-up reminders. Early spay/neuter provided the potential for 100% compliance by requiring puppies be neutered before being adopted out. However, only a small percentage of pets are acquired from animal shelters,
so neutering these animals can only have a small effect on the overpopulation problem. If veterinarians were to recommend neutering pups and kittens at an early age, a significant decrease in unwanted animals could result.
These
studies indicate that early spays benefit the animal, the owner, animal population control, and the veterinarian. The animal benefits because the anesthesia is fast and uneventful; surgical procedure is well tolerated and animals
recover faster. If made part of the standard puppy vaccination program, it would also benefit owners by decreasing the number of veterinary office visits necessary upon acquiring a new pet. This convenience to owners would lead to
increased compliance on their part and thereby decrease the number of unwanted dogs produced each year. The veterinarian benefits because spays and neuters at 6 to 7 weeks of age are easier and faster than at 6 to 7 months, they
help reduce animal overpopulation. It also gives veterinarians the opportunity to interact with new owners and breeders as well as be seen as leaders in animal welfare in our communities.