ESP - Early Sterilization Program
New Views on Neutering

Everyone seems to have an opinion when it comes to 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 inter-male 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 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 and cats that are neutered before puberty usually will not develop undesirable behavior.

Boon to Pure-bred Breeders

Dr. Michael Aronsohn, director of the Early Sterilization Program at the Massachusetts SPCA's Angell Memorial Hospital, sees ESP as a boon to pure-bred dog breeders. Pet quality puppies may be neutered as early as 6 weeks of age. Dr. Aronsohn and his staff have neutered several hundred puppies and kittens with no ill effects.

At an animal shelter in Medford, Oregon, over 8000 puppies and kittens neutered at 8-12 weeks have shown no undesirable effects. Dr. Dick Rosebrock, Mariposa Veterinary Service, has performed ESP since June of 1993, on over 400 puppies and kittens with no reported adverse effects. Check with your veterinarian about early neutering.

Mandatory Neuter Policies

The pet population problem in the United States has reached enormous proportions. In 1987, for example, between 6.3 and 10.4 MILLION dogs were euthanized in shelters. Most animal care facilities have mandatory neuter policies which require the owners adopting puppies and kittens to have them neutered at 5-8 months of age. However, follow-up and enforcement of the policy is difficult at best. Compliance averages only 50-60%.

For sterilization programs to be effective, all non-breeding animals should be neutered prior to the onset of puberty, and compliance rates must be improved! ESP by shelters brings the compliance rate to 100%.

Neutering Studies

Questions regarding the appropriate age to perform gonadectomy and the safety of anesthetizing young puppies have been addressed and published. 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.

In Practice

Some shelters and veterinarians in private practices are currently performing ESP, but it's also important for breeders to understand why individual veterinarians may choose not to perform early neuters. An eight-week old puppy is not just a smaller version of an eight-month old puppy. There are important differences between the two in factors such as respiratory and cardiovascular physiology, drug metabolism and thermoregulation. Few practitioners have accumulated a significant amount of experience in anesthetizing very young puppies on a regular basis, since there are not very many situations which call for anesthesia that young.

Most practitioners are very comfortable with the anesthetic and surgical protocols they have developed for neutering older puppies/kittens and young adults and are reluctant to change.

Owner Responsibility

Responsible pet owners can...and should...make a concerted effort to insure that all pet puppies and kittens are neutered. Fulfillment of this duty brings all of us closer to breeding fewer dogs and cats and conquering the pet overpopulation problem.