By Janet McAfee

Zeuterin, a non-surgical neutering procedure for male dogs, is a game changer in the effort to solve the world’s pet overpopulation problem. Zeuterin is an injectable all-natural zinc solution now approved by the U.S. Food and Drug Administration. The product has been in use for many years in Mexico, Bolivia, Columbia, and Panama, countries where animal populations are at the crisis point.

The Fantasy Springs Casino hosted a low cost pet sterilization clinic last week for low income Coachella Valley residents where Zeuterin was offered. While female animals were spayed in the Animal Action mobile clinic, male dogs were directed into a convention room for the Zeuterin procedure. The animals arrived in a calm procession, wagging their tails, happy to be on an outing, and oblivious to what was ahead.

The 3 day clinic spayed 84 female animals and zeutered 98 male dogs. This clinic was a collaborative effort by local resident Kim Hardee of Coachella Animal Network (CAN), Animal Action League, Loving All Animals, and ABC Recovery Center. ARC Sciences, the company that developed the product, donated the Zeuterin through their ARC Charities division which assists nonprofits. Pictured here is a German Shepherd being Zeutered, and White Girl, a 6-year-old female bulldog after she was spayed.

Gene Chou, a 4th year veterinary student at Western University, was there to receive certification in Zeuterin. He explains, “For me, this shows there is an alternative way to do castration. And I see that it works. There is always some risk with anesthesia, and now you can achieve sterilization without that risk. This gives pet owners another option.”

This low cost procedure takes only 30 minutes. The dog receives a mild sedation, and the zinc compound is injected into each testicle, killing the cells that produce sperm. The testicles shrink a bit, but remain visible, which is important to some pet owners concerned about appearance. A small “Z” is tattooed near the scrotum to indicate the animal has been altered. In most states, including California, veterinary technicians can perform the procedure if supervised by a vet.

Most people would agree that we need to spay and neuter more dogs and cats in order to prevent the birth of unwanted animals. Over 6 million cats and dogs are euthanized yearly in our nation’s public shelters. Over 34,000 animals were euthanized in San Bernardino and Riverside county shelters in 2011, a horrific tragedy for the animals and a great expense to the public.

Dr. Byron Mass, a Zeuterin master trainer and veterinarian in private practice in Oregon, oversaw the Zeuterin clinic at Fantasy Springs. He points out that including Zeuterin is an option that may reduce the euthanasia rate for shelter dogs. Dr. Maas explains, “With Zeuterin, adopted animals don’t have to wait for the surgery schedule. With more animals adopted faster, shelter kennel space is freed up.” More California veterinarians are now including Zeuterin in their services. Animal Samaritans in Thousand Palms has the only veterinarians certified in this procedure in the Coachella Valley.

Zeuterin is not without its critics. Some animal experts complain that it doesn’t necessarily eliminate hormone-related behaviors such as roaming, aggression, and marking. Zeuterin reduces the testosterone level by 50%, as opposed to 100% hormone reduction that takes place in surgical neutering. Zeuterin supporters point out the retention of 50% of the testosterone may enhance bone growth and reduce ligament injuries.

One drawback is that dogs who are Zeutered may still be fertile for up to 60 days. So you will need to keep Charlie in the house and away from girls for awhile.

Does Zeuterin change behavior? More long term studies are needed. The FDA issues the following statement on this question, “As with surgical castration, secondary male characteristics (roaming, marking, aggression, or mounting) may still be displayed.” There is no guarantee that any type of castration will change a dog’s behavior, as a lot depends on the dog’s age, breed, prior training, and past behavior.

Kim Hardee adds, “Zeuterin is the perfect solution for low income pet owners to control population, and it makes it affordable for them to obtain dog licenses which are significantly cheaper for sterilized animals.”

Believe it or not, Zeuterine was first used on human beings in order to help control the human population problem in China. However when it was discovered that the procedure greatly reduced the libido of the men participating, the program quickly ended! Now the procedure is used exclusively on male dogs. Research is underway to develop a non-surgical sterilization product that will work on cats and on female dogs.

Pet owners in this country can decide for themselves which method they prefer. Few would dispute how valuable Zeuterin is in communities where there are limited resources. Veterinarians who set up “clinics” in the middle of jungles and in third world country villages will find Zeuterin of great value. It is another tool in our arsenal to prevent the suffering experienced by unwanted animals that roam our landscape and fill our shelters. For more information go to or Google “Zeuterin”.