Who else would we use in a story about animal neutering? (Getty Images/Toby Canham)

Today is a proud day for the Humane Society of the United States, though it might be less fun for your dog. The Humane Society is marking World Spay Day today, an annual campaign to promote the importance of neutering pets as a way to control populations and reduce the number of unwanted animals that shelters do not have the capacity to care for.

Millions of animals are euthanized by humane shelters every year, and nearly all of them are those who went unwanted, WTOP reports:

According to HSUS, four million animals are euthanized at shelters every year. Most of those are, 3.7 million , are unwanted cats and dogs.

Shelters around the country and in the D.C. region say the need for spaying and neutering pets is clear. There are just too many animals for too few homes.

In D.C., Lucky Dog Animal Rescue, a shelter based in Burleith, is also celebrating World Spay Day by taking over the Uptown Tap House in Cleveland Park with a happy hour for people,and their pets but not their pets.. (There are drink specials for the humans.)

And though there are plenty of jokes to be made about getting one’s pet spayed or neutered, it’s a very important process. Risks for certain types of cancer can be reduced by as much as 90 percent.