Spay and Neuter

Unneutered male dogs are overwhelmingly implicated in dog bites, both fatal and nonfatal. In fact, this single factor is more strongly correlated to fatal attacks than the dog’s breed or the manner of containment.

However, correlation does not equal causation.

  • Does spay/neuter actually make a dog less aggressive?
  • Or does it simply reduce the dog’s urge to roam, thereby keeping the dog at home, away from strangers and out of dog fights?
  • Or is it that many unaltered dogs’ owners are less likely to properly contain and socialize their dog? Some people may actually want an aggressive dog, and therefore would not follow the conventional wisdom to spay or neuter to reduce aggression. Others simply may not have the money or interest to spay/neuter, socialize, train, or properly manage their dog.
  • Or is it that the population of unaltered dogs outnumbers the population of altered dogs by such a degree that it is only natural that unaltered dogs are involved in more bite incidents?

There is a noticeable lack of scientific study regarding the apparent link between aggression and reproductive status. Recent studies suggest that this link is much weaker than popular wisdom would have it.

Nevertheless, considering the strong correlation between intact dogs and dog bites, it seems wise as a preventative measure to encourage spay/neuter. There are, of course, health benefits for the animal. Spay/neuter also reduces the number of accidental litters. This helps a community control the pet population. It is a win-win situation.

Spay/neuter also provides an opportunity to educate dog owners about their responsibilities, to discourage the use of dogs for guarding or protection, and to provide additional resources for dog owners who are dealing with a dog’s behavior problems. It has been suggested, as well, that when an individual is encouraged to spay/neuter their pet, this helps to reframe the animal as a valuable object requiring an investment of money and time, rather than a cheap disposable toy.

By offering low-cost and free spay/neuter for pet owners, communities have been successful in increasing their rate of altered pets.

Low-Cost or Free Spay/Neuter

The importance of the availability of low-cost or free spay/neuter cannot be stressed enough. Nathan Winograd and others have asserted that one of the leading reasons people do not spay or neuter their pets is due to cost and lack of access to spay/neuter programs.

In areas where low-cost or free spay/neuter is available, studies have found that an increased number of individuals take advantage of the service. That is, it is not the same people who would have altered their pet regardless of the cost. Low-cost and free spay/neuter services pull in people who would otherwise not have had their pet altered.

Mandatory Spay/Neuter (MSN)

To date, not a single study has shown that MSN can definitively impact pet overpopulation or dog bite rates. In fact, MSN has shown to be expensive and difficult to enforce. Many areas that have implemented MSN have seen an increase in the number of animals surrendered to shelters, and an increase in their euthanasia rate as well.

Additionally, when low-cost or free spay/neuter programs are not implemented in conjunction with MSN, people who cannot afford to alter their pets simply do not do so. And now that these people are in possession of “contraband”—unaltered pets—the fear is that they will “go underground,” meaning their pets will not get proper vet care or training.

Prominent leaders in the no-kill movement such as Nathan Winograd have consistently spoken out against MSN. Voluntary low-cost and free spay/neuter programs typically show much more success than mandatory spay/neuter.

Spay/Neuter or Penalty Before Reclaim

Some animal shelters have instituted a policy wherein unaltered, unlicensed, stray animals that are impounded by animal control may only be reclaimed by the owner if the animal is first spayed/neutered, or if the owner pays a hefty fee. This would theoretically accomplish a host of things, including increased licensing, fewer stray pets, ability to reunite lost pets with owners rather than filling the shelter, and so on.

At least one community had some success with this approach on a short-term basis, but as no followup was done and the shelter involved no longer contracts with animal control, it is not clear whether this approach had or would have had any long-term impact on dog problems or dog bites.

Sources and Resources

Frank, Joshua M.and Pamela L. Carlisle-Frank. “Analysis of programs to reduce overpopulation of companion animals: Do adoption and low-cost spay/neuter programs merely cause substitution of sources?” Ecological Economics, Volume 62, Issues 3-4, May 15, 2007.

Kustritz, Margaret V. Root, DVM, PhD, DACT. “Determining the optimal age for gonadectomy of dogs and cats.” JAVMA, Vol 231, No. 11, December 1, 2007.

Winograd, Nathan. Redemption. Almaden Books, 2007.

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