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  • Why not just promote regular spay/neuter?
    Spay or neuter surgery is an essential, life-saving procedure. Its increasing acceptance and use over the past few decades has saved countless dogs and cats. But spay/neuter needs a revamp! Spay/neuter surgery works best for animals who have caring guardians who can pay for the procedure and supervise their recovery. Unfortunately, stray animals do not have this luxury. Current programs in place for strays — such as TNR (trap, neuter, return) — capture stray animals off the streets, bring them to a veterinarian to undergo spay or neuter surgery, and then release them again. This process requires a great deal of time, effort, and money. It requires the expertise of veterinarians, who are often in short supply. These hard-working rescuers could use another tool in their toolbox. Americans donate well over $1 billion each year (a very conservative estimate) to animal groups, most of which are dedicated to rescuing homeless dogs and cats. The U.S. government also spends at least a billion taxpayer dollars on dealing with homeless animals each year. A significant amount of progress has been made with rescuing dogs in the U.S., but there are still tens of millions of free-roaming cats in this country. And in spite of all these efforts, many dogs, cats, and other animals are still killed in shelters due to lack of homes. Our group's primary focus is global. Every year, hundreds of millions of stray dogs and cats continue to suffer for their entire brief lives, while living long enough to give birth to puppies and kittens who also struggle to survive. Globally, free-roaming dogs and cats are suffering and dying in horrible ways – being poisoned, shot, starving, hit by cars, deliberately abused, and so on – because most countries are either unwilling or unable to spend billions of dollars every year to help homeless animals. That’s why we’re focused on an oral (edible) product to spay or neuter, since it’s much easier to feed a free-roaming animal than to catch him/her and do surgery or even to give an injection, which some groups are working on developing. We feel there’s a lot of room for improvement in how the pet overpopulation crisis is being handled, and oral nonsurgical sterilization could be a game-changer. It’s taking longer than we would like, because we are severely underfunded, but we’re working very hard to make this happen for animals! Our nonprofit, science-based mission is to end the #1 cause of suffering and death for dogs and cats worldwide — overpopulation — by developing a one-dose Cookie that, when completed, will spay or neuter a stray, without surgery! The wider goal? Nothing less than ending the global pet overpopulation crisis and ending the terrible suffering it causes. We hope you can help by supporting this work, by forwarding our emails to friends, or by telling them about our website
  • When will the Spay and Neuter Cookie be available?
    Our Spay and Neuter Cookie is in the research and development stage and is not completed yet, because our project remains severely underfunded. However, we are proceeding at the grassroots level with the funding we do have. We are delighted to report that our largest study ever is well underway, including over 100 Pilot Pups who we have rescued from the streets, fed a trial One-Dose Spay and Neuter Cookie, and adopted into loving homes. The answer is clear. First, the good news is that because the science is very strong, we believe that the real question is not will the Cookie succeed … but rather, the real question is when? To put this in perspective, we firmly believe that if adequate funding had been in place for the last 3 to 5 years, the world would have the Spay and Neuter Cookie by now. The only thing holding it back is the lack of sufficient funds. The bad news: This is taking longer than it should, simply because the project is being financially starved. Sadly, it receives only 10% of the funds that are needed. The cost to perform this work at a normal pace is at a very minimum $3 million per year for 3 consecutive years. Instead of $3 million per year, this project has only received an average of $300,000 per year … even though a Spay and Neuter Cookie would prevent the suffering of millions of innocents. This work is classified as the "development of a veterinary pharmaceutical drug." It is work that is normally only performed by billion-dollar pharmaceutical companies. As you may know, the pharmaceutical companies have shown little to no interest in a product like the Spay and Neuter Cookie, because they deem it to be not profitable enough. Drug companies of course prefer products that have a repeat customer base. Products whose customers return every month to buy more product, month after month and year after year. The longer the better. The drug companies describe our work (to develop the Cookie) not as a self-sustaining business, but instead, as a self-defeating business. Why? Because we are designing the Cookie to eliminate its customer base. It's no wonder the drug companies are not involved. Unfortunately, even the 10% that we have to work with is at risk. Each year we must take time and attention away from the work developing the Cookie, and instead spend that time and attention working very hard to raise the needed funds. If we did not do this, there would be zero funds to work with. We receive no government support. No corporate support. We have no reserves. No trust fund. No endowments. Accomplishing this mission relies entirely on gifts from individuals who care, like you. We will not let these problems stop us. We will continue working at the grassroots level, at the grassroots pace, with the grassroots funds we painstakingly raise -- until we succeed. We must never despair over the lack of support. This is not the first time in history that a great idea has been shunned by the establishment and the powers that be. Instead, we must have vision. We must continue to look beyond the obstacles. We must never lose sight of the suffering of the world’s estimated 600 million stray dogs, who reproduce and give birth to over one billion homeless puppies each year -- the survivors of which then repeat this Cycle of Suffering. Once we have succeeded in developing a Cookie for dogs, we must do the same for cats, who are also suffering horribly due to the overpopulation crisis. What is at stake for the animals is unprecedented: a single project, designed to end the suffering of hundreds of millions of animals, through a Cookie. Once we have succeeded in developing the winning formula for the Cookie, we will put it to work in field trials in parts of the world where the need is the greatest. In parts of the world where the suffering is the most severe. In places such as India, Egypt and Mexico, to name only a few, where field trials will allow the Cookie to be used as a humane and effective alternative to poison. As you may know, although it is illegal in the U.S., inhumane poisoning is the #1 method used to kill stray dogs around the planet. It is our view that, for animals, developing the Cookie is a matter of global significance, and success is our only option. You can help by introducing your friends to this project at We also ask caring people to make a traditional tax-deductible gift, of any amount by mail via the address below, or through our website at No gift is too small. No gift is too large. Every gift helps. No matter the amount. We thank you more than words can say. We also encourage you to please take a valuable and important step-up, by becoming a monthly contributor by mail via the address below, or through our website at Whether it's $5, $25 or $100 a month, it absolutely adds up and it absolutely helps. Please check out our website Science page to read more about our current work to produce the Cookie! We can never thank you enough for joining us in ending the Cycle of Suffering.
  • What about cats?
    Thank you for asking and for caring about our work to prevent the suffering of stray cats due to the overpopulation crisis. Our name may be 600 Million Dogs, but, yes, cats are a core part of our mission! Our nonprofit science-centered mission is to significantly reduce animal suffering on a global scale by developing a safe, edible, one-dose, permanent-lasting birth control Cookie for stray dogs and cats. We would love to be developing the Cookie for cats right now … … the problem is, our efforts receive only 10% of the funds that are needed. To make these funds stretch as far as possible, our current studies focus on dogs. The reason we chose to start with dogs is because most of the current research on animal birth control has focused on dogs, not cats. This means we can base our efforts on current, existing research. We believe this is the fastest way to the finish line. This kind of work is incredibly expensive. For every day of our studies, we need to pay for rescue, vet care, active ingredients for the Cookie, surgical spay/neuter, creation of digital slides of ovarian follicles, examination of results by histopathologists, and much more. The only thing holding back our ability to help suffering stray cats is the lack of funds. This work is classified as the "development of a veterinary pharmaceutical drug." It is normally only performed by billion-dollar pharmaceutical companies. But these companies have shown little interest in a product like the Spay and Neuter Cookie. They don’t consider it profitable enough. Accomplishing this mission relies completely on gifts from people who care, like you. We will not let these challenges stop us. We will continue working at the grassroots level, at the grassroots pace, with the grassroots funds we painstakingly raise -- until we succeed. As you may know, in the U.S., it's estimated that over 1 million homeless cats are killed in shelters each year, and that almost 80% of stray kittens don't survive beyond their first 6 months. For those who do make it, their lives are filled with hunger, disease, and danger, and their average lifespan is only 4 years. That's a fraction of the lifespan of a beloved indoor cat. Worldwide, many countries have no laws protecting cats from abuse. So in addition to suffering from starvation and neglect, cats are poisoned or hunted — not just by cruel individuals, but even by governments. Such innocent, loving, and beautiful animals, born only to endure a brief life filled with suffering — it breaks our hearts. But we can work together for a better future for cats! We will keep working tirelessly until the Cookie is complete. Our work depends on the support of forward-thinking, caring people like you. If you can't donate right now, sharing our mission with your friends and family is a free way to make a huge impact. So please spread the word!
  • How are your current studies conducted?
    Team 600 rescues stray dogs from some of the world’s most cold-hearted streets. The dogs are given the veterinary care they need for any illnesses or injuries they may have suffered during their lives as homeless strays. Once healthy, they are given a single trial Cookie formulated with a safe, low dose of the birth control ingredients we are studying. Then they are adopted into loving homes. We call them "Pilot Pups." Each rescued Pilot Pup plays a crucial role in our groundbreaking pilot studies. After they've eaten the single trial Cookie, each Pup undergoes a routine spay or neuter surgery, during which their ovaries or testes are removed as usual. The big difference is, instead of throwing away the tissues, we preserve them, and our veterinary pathologists microscopically examine them, allowing us to determine the effectiveness of the trial Cookie. It goes without saying that in our studies, the health and happiness of our adored Pups is the highest priority. They are never in a laboratory. Our studies are designed to develop what will be a revolutionary One-Dose Spay and Neuter Cookie. Once completed, the One-Dose Cookie will spay or neuter a dog or cat, without surgery. For more details, please check out the materials at the "Science" tab of this website.
  • How is this different from animal testing?
    To be clear, no animals are harmed in our work. No animals are killed. All of our animals are animals we have rescued. Our animals are never in a laboratory. Instead they are in a private veterinary clinic, no different from the veterinary clinic we all take our own companion dogs to. They are cared for in the private veterinary clinic for around 40 days. During this time they receive veterinary care and standard health tests — just like human health tests. They are available for adoption after this period. Ensuring the safety and well-being of animals is central to our mission. The Pilot Pups are fed a trial Cookie that contains a low, safe dose of the ingredients we are using. We are modifying existing birth control formulas and only increasing the dosage by tiny amounts to ensure that the dogs are safe and healthy. Again, the safety and well-being of our Pilot Pups is our number-one priority. This is very different from conventional animal testing, which uses animals as an experimental tool and deliberately kills large numbers of animals through massive overdoses. As you may know, 600 Million Dogs' founder and president, Alex Pacheco, has a long, outstanding track record of pioneering advocacy for animals. As co-founder of the largest animal rights organization in the world, PETA -- where he served as Chairman for 20 years before leaving -- his commitment to protecting animals is unwavering. In fact, Alex worked undercover to expose horrifying experiments on monkeys in the famous Silver Spring Monkeys case. His work led to the world's first police raid on an animal laboratory. For more information about his remarkable record of defending animals, please visit
  • What are the ingredients in the formulas you’re testing? Are the formulas safe?
    The safety of our rescued Pilot Pups is our #1 priority. The welfare of our Pilot Pups is of utmost importance in our studies. Our Pilot Pups live in loving homes, not laboratories. We take precautions and go out of our way to ensure that each trial Cookie is as safe as possible, based on using ingredients and amounts that we already know to be safe. For the safety of the Pilot Pup, to study variations in formulas, we only increase key ingredients by very small, controlled amounts, one tiny step at a time. This is a significant factor in why it is taking so long to perfect the formulas. In contrast, a for-profit drug company would not typically follow our one tiny step at a time approach; instead they would increase the dose as high as possible and as fast as possible, to cut costs. The most effective compound identified so far is Vinylcyclohexene dioxide (VCD), a synthetic chemical with the CAS No. 106-87-6 and molecular formula C8H12O2. This compound, in a multiple-dose formulation, has already received approval from the U.S. Environmental Protection Agency (EPA) for inducing infertility in rodents. The key distinction between the existing rodent formula and the new formula being developed by our team lies in the dosage requirement. While the rodent formula necessitates multiple doses to be effective, our objective with formula 600 is to achieve the desired result with a single dose, specifically in the form of the One-Dose Spay and Neuter Cookie. Previous studies have demonstrated that VCD, when used appropriately (e.g., in dogs), is safe. However, it's important to note that VCD in its pure, undiluted form is highly concentrated and caustic. Consequently, this concentrated form is unsuitable for direct use due to its corrosive nature and must be diluted.
  • Where do the Pilot Pups live?
    Our Pilot Pups live in loving homes, not laboratories. After a stray dog is rescued from the streets by the 600 Million Dogs team, they are taken to the vet to get the help they need. Once recovered, they are given a single safe dose of the formula we are testing, and then they are adopted into a loving forever home!
  • Can I adopt a Pilot Pup?
    At the moment, our grassroots studies are taking place outside the U.S., and our rescued Pilot Pups are being adopted in their home country in South Asia. Unfortunately, the process of transporting animals to the U.S. from overseas — especially from countries where rabies is prevalent — is expensive and complex, so they are not available for adoption in the U.S. at this time. In the meantime, as you know, there are hundreds of thousands of dogs in the U.S. who desperately need loving homes. If you have room in your heart and home and would like help finding one, please visit or and visit local rescue groups and shelters in your area!
  • Is it possible to develop a spay and neuter Cookie?
    The Cookie may be hard to imagine because it is not finished yet. We firmly believe that with adequate funding, it can be achieved. Most of us are not inventors, innovative scientists, or visionaries, so we have a hard time picturing things before they exist — and as soon as they exist, we take them for granted! The birth control pill was initially invented to address menstrual disorders and was found to have the "side effect" of preventing pregnancy. Here are some examples of innovations from the past 70 years that most of us wouldn't have predicted: Also, as you may know, the founder of 600 Million Dogs, Alex Pacheco, was one of most important pioneers of the animal rights movement in the U.S., before most people ever imagined or heard of such a thing. We feel there is a lot of room for improvement in how homeless animals are treated, and this requires the willingness to explore new options and take one step at a time to make change happen. That is why we're looking beyond surgical spay/neuter. There are others working in the field of nonsurgical sterilization of animals, but they are mainly focused on injectable products. We are focused on developing an oral product because we believe that will be the most suitable for stray animals, who are desperately in need of help. As you know, our nonprofit science-centered mission is to end the #1 cause of suffering and death for dogs and cats worldwide — overpopulation — by developing a safe, one-dose Cookie that, when completed, will spay or neuter a stray, without surgery. This is not work that can be done by just anyone. Although we have a small team of part-time scientists, we are working hard to raise the funds necessary to hire additional skilled scientists to devote their time, knowledge, creativity, and problem-solving skills to achieving this goal. We have a grassroots study in progress right now, with over 100 rescued Pilot Pups. Our recent histology results are promising, though it is too early to tell whether they will be consistent. For updates, please stay on our email list and visit our website's "Science" page. Thanks again for caring about animals!
  • I can't afford to donate. How else can I help?
    We totally understand that sometimes donating is not an option. We would really appreciate it if you would help stray dogs and cats by sharing our emails with friends and family. If you are not already subscribed, you can subscribe at You can also help by sharing our Facebook or Instagram posts! On Facebook we're at On Instagram we're at If you are interested in volunteering, please read our website thoroughly so that you understand what we do (for example, we don't run an animal shelter). Then send a resume or list of your job skills to Thanks!
  • How do I make a one-time donation on your website donate form?
    To make a one-time donation on our website click here.
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