Behavioral Benefits of Neutering Your Pet

by Mark Hale, DVM

Bolivar, MO

            One of the common questions I get when recommending a neuter for a family's male pet is "Why should I do that? He cannot get pregnant, can he?" And of course, the answer is no, he cannot get pregnant. But many behavioral and health benefits can be gained by neutering, especially at a young age.

            Neutering, or castration, in a male dog or cat removes the source of testosterone, the primary male hormone. In a study by the University of California at Davis, 57 dogs exhibiting various behavioral problems while intact were then neutered between 2-7 years of age. Follow-up studies showed that in almost half of the study dogs, urine marking, mounting, and roaming behaviors decreased by 90%. The remaining dogs showed a 50 % decrease in these behaviors. Neutering also lessened aggression towards canine and human family members, but to a lesser extent.

            Roaming behaviors are often responsible for dogs getting injured in fights or other trauma, hit by cars, and being lost. Many of these traumatic injuries can be very serious, or even life threatening, as well as expensive to treat. Many clients are so much happier with their dogs after neutering because their behavior has improved so much. I have even heard one lady say numerous times that "Jack could be the poster child for why you should have your dog neutered". The health benefits include the decreased incidence of certain cancers and diseases, but the decreased traumatic injuries mentioned above are probably more important. In my experience, it is better to have the procedure done at less than 1 year of age, because later in life some of these behaviors may have become such a habit that even the decreased testosterone after surgery won't change the undesirable actions. Some studies have also shown that intact canines are more likely to bite or attack people, including children. In my opinion, any family dog showing aggressive tendencies should be neutered immediately.

            For cats, the behavioral benefits of neutering can be even greater than for dogs. Another study at UC Davis found that "castration greatly reduces or eliminates urine spraying, roaming and fighting with neighborhood males in 90% of male cats." This study also found that 50% of the cats dramatically decreased—by 80%­­-- their roaming and fighting behaviors in the first week, although the remaining study cats demonstrated a more gradual decline. For indoor cats another big benefit is the decreased smell of the urine. The strong offensive odor of an intact tomcat can be overwhelming and seems to decrease in intensity within days of castration.

            On last reason to have your pet neutered is the pet overpopulation problem present in this area and all across the country. Every week in the local paper there are lots of listings for pets "free to a good home". Shelters are overrun with pets needing homes, and millions are euthanized each year to make room for the new ones coming in. And while none of us know the real answer to this problem, we should not contribute to it either. If you plan to breed your pet, please make sure that you can devote the time and money necessary for it to be done correctly. Avoiding unwanted or unneeded litters is one way we can all help to lessen the overpopulation problem.