Dogster is reader-supported. When you buy via links on our site, we may earn a commission at no cost to you. Learn more.

Lifestyle

Can a Food That Sterilizes Dogs Solve the World's Stray Problem?

Nicole Cosgrove
By Nicole CosgroveUpdated on June 16, 2026
Share
half a dozen stray street dogs roaming in a residential area in north india

He's the person who gave birth to the animal rights movement in the United States. Heck, he's the reason the phrase "animal rights" became a household word. His work while at People for the Ethical Treatment of Animals (PETA) helped to save millions of lives. Now he's focused on preventing the births of stray dogs.

In 1980, Alex Pacheco co-founded PETA. He grew the organization from a few people in a basement to the world's largest animal rights organization. Specializing in undercover investigations, litigation, and lobbying, Pacheco served as the organization's chairman for 20 years, making people around the world change the way they think about how animals are treated.

I first met Pacheco in 1993, when I was a fresh-out-of-college intern at PETA. I later worked for him at the New England Antivivisection Society. I even bailed him out of a Miami jail one New Year's Eve after we protested elephants being forced to march down Biscayne Boulevard in the parade. I'm proud to have called him a friend for more than 20 years. There are few people I admire as much as I do him.

Pacheco and PETA parted ways in 2000, and since 2009 he’s been focusing his efforts on the global pet overpopulation crisis. His nonprofit group, 600 Million Dogs, is working to develop a dog food that will sterilize dogs and, he believes, end the cycle of suffering for the 600 million homeless, diseased, and starving stray dogs around the world -- without surgery or euthanasia.

Unlike human birth control pills, Spay Food will work in a single dose for both male and female dogs. A formula for cats is also in the works.

Because it is still in development and because there are many legally binding confidentiality agreements in place, Pacheco could not disclose the actual formula. He was able to tell me that zinc is one of the active ingredients. Variations of zinc, when combined with other ingredients, are known to be capable of sterilizing dogs and cats.

He was also able to tell me that the finished Spay Food formulas will be oral and delivered in the form of treated, canned dog food. Flavoring will be determined after the formulas are finalized. "Based on the many years of data on the ingredients we are using, there are no negative side effects when used as intended (even if dogs eat multiple portions);

will not harm people, will not harm other animals, and will not harm the environment," Pacheco explains.

Spay Food would also help to prevent the deaths of people who die from rabies. More than 95 percent of the 55,000 people who die from rabies worldwide each year receive the infections from a stray dog bite, according to the World Health Organization.

"We have found a way to end this cycle of suffering without having to capture the animals, without surgery, and without euthanasia," Pacheco says. "I am certain that this new super birth control for dogs will make a dramatic, historic difference for hundreds of millions of animals."

The 600 Million Dogs organization still has a long road ahead of it. Why? Money. Pacheco notes that all of the people working on this cause -- from the chemists, to those keeping the website current, even himself -- are all volunteers. "For the sake of the world's starving stray dogs, we must finance all of this ourselves," he says. And it's an expensive undertaking. A proper budget to complete the clinical trials for a single-dose formula version of Spay Food is between $1 million and $4 million per year, depending on which country much of the work is carried out in.

Image Credit By: Zlatko59, Shutterstock

The organization has targeted 60 countries with a high stray-dog population to receive the food once available, including Mexico. In Mexico City, there are approximately three million stray dogs. Mexico City authorities report that they capture and kill an estimated 20,000 dogs per month in their city alone. There are more than 16,000 dogs and cats living on the streets in Manzanilla, a city in Colima, Mexico.

Part of the problem is that spaying and neutering is not widely accepted there. Many Mexican men believe that doing so will "make the dogs gay," as reported by Smithsonian Magazine. This belief was also explored in a documentary about Mexican street dogs called Companions to None, which exposes the animal cruelty and overpopulation crisis in the country.

Common methods of animal control in Mexico City are not pleasant. Stray dogs who are caught are killed by electrocution, and the ones who are not caught are fatally poisoned. Eventually, with Spay Food delivered, Pacheco says, the number of stray dogs will be significantly reduced.

Food distribution also will vary by country. In some countries, veterinarians will be allowed to administer the products, and in others, only municipal health departments (such as rabies control or wildlife agencies) will be able to dispense the food. Some may allow registered nonprofit shelters to do so, and others may allow individuals to acquire the products directly.

Why stray dogs?

"After more than 30 years of working full-time protecting animals, I have come to believe that Spay Food can and will save more animals and will prevent more suffering than any other single project in history, and

one that can be accomplished in our lifetime,” Pacheco explains.

"I believe in spending my time on whatever will do the most good, whatever will save the most animals, whatever will end the most suffering. It's not about what is my favorite project. It’s about which project will help the most animals," he says. "At this stage, our crucial goals are to raise desperately needed funds to be able to hire full-time employees such as chemists to work on Spay Food and to continue working on the clinical trials."

Image Credit: Anton Gvozdikov, Shutterstock

For more information or to volunteer, visit 600MillionDogs.org and the organization's Facebook page.

Read more about spay/neuter:

About the author: Jennifer Cohen is a long-time animal advocate. She lives in South Florida with her twin daughters, Sydney and Alexandria, who are winners of the Animal Hero Kids Award 2014; their rescue dogs Jake and Max; and their rescue parrot, Sam.


Featured Image Credit: LSP EM, Shutterstock

The Dogster Newsletter

Expert dog care, straight to your inbox

News, insights, expert advice, and everything dog.

No spam — unsubscribe anytime.

By signing up, you agree to our Terms & Conditions and Privacy & Cookies Policy.

Click a star to rate. You can leave written feedback afterwards. (We read all feedback.)

Nicole Cosgrove
Authored by

Nicole Cosgrove

Leave a Reply

You're very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let's have a positive and constructive conversation.

How Bhutan Kept Its Stray Dogs Under Control: A Story of Success (Vet-Verified)

How Bhutan Kept Its Stray Dogs Under Control: A Story of Success (Vet-Verified)

Have you heard of the Kingdom of Bhutan? This small country is nestled in the Himalayas between Tibet and India and is well-known for how it managed to keep it…

Misty Layne
By Misty Layne · 2 months ago
Beach Dog Rescue Surpasses 7,000 Spay/Neuter Milestone in Yucatan, Mexico

Beach Dog Rescue Surpasses 7,000 Spay/Neuter Milestone in Yucatan, Mexico

In the heart of Yucatan, Mexico—about five hours from Cancun—a small farm has become a haven for dogs awaiting a new life. Beach Dog Rescue, run by Heather and…

Nicole Cosgrove
By Nicole Cosgrove · 1 month ago
Inside Soi Dog Foundation, the Organization That Has Vaccinated & Sterilized Over 1.7 Million Dogs & Cats

Inside Soi Dog Foundation, the Organization That Has Vaccinated & Sterilized Over 1.7 Million Dogs & Cats

For more than 20 years, Soi Dog Foundation has been creating lasting change for stray dogs and cats across Asia. What began as a small grassroots effort in Phu…

Nicole Cosgrove
By Nicole Cosgrove · 2 months ago
Zinc Neuter for Dogs: What Is It, Risk & Ethics

Zinc Neuter for Dogs: What Is It, Risk & Ethics

Neutering is a word most everyone can immediately recognize, it means to sterilize a male animal. Everywhere you look, you see people advocating for spay and n…

Ashley Bates
By Ashley Bates · 1 month ago

Is It Okay to Feed Stray Dogs? Vet-Approved Reasons & Advice

When you see a stray dog, it can be tempting to bring them food. However, that may not always be the best decision. Feeding a stray dog can cause unexpected pr…

Jordyn Alger
By Jordyn Alger · June 17, 2026
Is It Okay to Feed Stray Dogs? Vet-Approved Reasons & Advice

Why Are There So Many Stray Dogs in India? History & Facts

India is home to a large population of canines, mostly owned by the country’s human population. However, there are also many strays in the country, so much so…

Nicole Cosgrove
By Nicole Cosgrove · June 16, 2026
Why Are There So Many Stray Dogs in India? History & Facts

How to Help Homeless Dogs: 14 Vet-Approved Ways

Approximately 6.3 million pets end up in U.S. animal shelters annually, almost half of which are dogs, some of which are euthanized.1 Fortunately, most are ado…

Chris Dinesen Rogers
By Chris Dinesen Rogers · June 16, 2026
How to Help Homeless Dogs: 14 Vet-Approved Ways

What Is the Dog Meat Trade? Vet-Reviewed Guide & How to Help End it

In many areas, dogs are treated as family members. However, the same cannot be said for every place on Earth. While dog meat is consumed to a limited extent in…

Chantelle Fowler
By Chantelle Fowler · June 17, 2026
What Is the Dog Meat Trade? Vet-Reviewed Guide & How to Help End it

The Movie "Petfooled" Changed the Way I Buy Dog Food -- and It Should for You, Too

In 2001, I read Fast Food Nation: The Dark Side of the All-American Meal. It explained not only what I was putting into my body at the drive-through window, bu…

Nicole Cosgrove
By Nicole Cosgrove · June 16, 2026
The Movie "Petfooled" Changed the Way I Buy Dog Food -- and It Should for You, Too

Pet Aquamation: The Eco-Friendly Alternative to Cremation Explained (Vet-Approved)

Saying goodbye to our pets is so tremendously heartbreaking, but unfortunately, it is a part of life and something that we can’t avoid, as much as we want to.…

Kathryn Copeland
By Kathryn Copeland · June 17, 2026
Pet Aquamation: The Eco-Friendly Alternative to Cremation Explained (Vet-Approved)

How to Hold a Dog Food Drive for a Rescue or Shelter: 9 Tips & Tricks

All dogs need to eat, including those at shelters and rescues. However, dog food can get surprisingly expensive when you’re feeding dozens of dogs at a shelter…

Kristin Hitchcock
By Kristin Hitchcock · June 16, 2026
How to Hold a Dog Food Drive for a Rescue or Shelter: 9 Tips & Tricks

Five Freedoms of Animal Welfare: Vet-Approved Explanation and Info

When you take on the responsibility of owning a pet, you are committing to making sure the animal has everything that they need to enjoy a good quality of life…

Ashley Bates
By Ashley Bates · June 17, 2026
Five Freedoms of Animal Welfare: Vet-Approved Explanation and Info

Love Dogs? So Do We! Join the Dogster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.

You may opt-out at any time. View our Privacy Policy for more information.

The Dogster app on a phone