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To Have or Not to Have Testicles

Pet Column for the week of July 19, 1999

Office of Public Engagement
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
By Sarah Probst
Information Specialist

My brother really doesn't want to neuter his dog. It's not because he wants to breed the
dog, but because he is just not convinced that the advantages of castrating outweigh the
disadvantage, namely, his belief that Theo will miss his testicles. So I recruited Dr. Brad
Coolman, a former veterinary surgery resident at the University of Illinois Veterinary Medicine
Teaching Hospital in Urbana, to address my brother's concerns.

Dr. Coolman has served in the U.S. Army Veterinary Corps. For three years he worked
with the military police dog program in San Antonio, Texas, which trained about 400 dogs
each year and was a referral hospital for military police dogs from around the world

Concern No. 1 "Castrated dogs are wimps."

"Many guys who don't want to castrate their non-breeding dog are concerned that losing
the testicles of a dog is the same as losing the manliness of the dog," says Dr. Coolman. "At
the Army facility most of the police dogs were male and many of them had been neutered
for medical reasons. The handlers, the majority of whom were macho-male types, were
often shocked to learn that their tough, aggressive dog was actually neutered." My brother's
claim that his dog will miss his testicles is anthropomorphism-attributing human
characteristics and feelings to animals.

Concern No. 2 "Why should I neuter my dog? He can't get pregnant."

Neutering reduces roaming behavior. My brother's dog, Theo, is a farm dog who could
roam to our neighbor's ground and potentially father an unwanted litter of puppies. Spaying
and neutering are the best way to reduce the 4 to 6 million unwanted pets euthanized each
year. Even though males can't get pregnant, they can sire multiple litters.

Concern No. 3 "I thought you said neutering would not change my dog's

Neutering can decrease roaming behavior, marking behavior, and some forms of
aggression, but genetics and training are more important contributors to your pet's behavior.
"I've seen many excellent police dogs, and I've never seen a recently castrated male
suddenly lose all its working drive," says Dr. Coolman.

Concern No. 4 "All neutered dogs are sleepy and fat."

People think neutered dogs are more sleepy and less playful than usual after castration. In
fact, those behavioral changes are typical of puberty, the stage of life when most neutering
occurs. The changes merely reflect your pet growing up. But don't blame obesity on being
neutered. Any dog can become obese. Obesity should be controlled through proper diet
and exercise.

Concern No. 5 "If I don't let my dog near unspayed females, why should I

The list of medical reasons for castration is convincing. "Testicular tumors are very common
in older dogs. If you don't have testicles you don't get testicular tumors," notes Dr.
Coolman. "Castration also prevents most diseases of the prostate: hyperplasia, prostatitis,
cysts, and abscesses. Unfortunately, castration does not prevent prostatic tumors."

Owners should castrate dogs who carry heritable diseases, such as hip dysplasia or other
congenital conditions, to make sure that undesirable traits and disease aren't passed on.
"Dogs that are cryptorchid, i.e., with one or both testicles that did not descend, should be
neutered," emphasizes Dr. Coolman. Cryptorchid dogs are at much higher risk of
developing testicular cancer, and the condition is hereditary.

Concern No. 6 "You're just telling me to do this because you're a girl. Do you tell
people to neuter girl dogs too?" my brother asks me as he scrambles for a last

People of both genders understand the benefits of spaying female dogs, but there still are a
few myths out there. It is not true that it is best to let your female have a litter of pups before
spaying her. "Spaying a dog before her first cycle decreases the risk of mammary tumors.
Spaying also decreases the risk of uterine infections, pyometra, abnormal estrus cycles,
cancer, and unwanted behavioral changes during heat cycles. It also helps deter unwanted
attention from intact male dogs in the neighborhood," adds Dr. Coolman.

When deciding whether to neuter your pet, don't put your own perceptions or feelings into
what your dog is thinking. Rather, study the medical and social benefits of having a
castrated non-breeding dog and discuss the issue with your veterinarian before making your