STEVE LEWIS/Durango Herald
Dog owners in Southwest Colorado who want to neuter their pet now can choose not to subject their pooch to the unkindest cut of all.
Stacee Santi, managing veterinarian at Riverview Animal Hospital, has substituted a zinc-based injection for sterilizing male dogs.
Approved by the U.S. Food and Drug Administration only four months ago, the zinc gluconate injection is not being used anywhere else in the region and only by about 100 veterinarians in the country, Santi said Thursday.
There apparently is no equivalent product being developed to neuter female dogs, an office staff member said Friday.
Ark Sciences, based in New York City, says its product is being hailed by groups that want to control canine overpopulation. Four million pets are euthanized annually in the United States.
The company sells its product, Zeuterin, only to veterinarians who have trained in the procedure.
Zeuterin, a play on the words zinc and neuter, was developed over years, with clinical studies beginning in 1999. Field trials on 10,000 dogs were conducted in Mexico, Santi said.
Zinc gluconate (a trace element) and L-arginine (an amino acid) are found in scores of health supplements used by people.
Chris Nelson, director of animal services at the Humane Society of La Plata County, sees the new procedure in a positive light.
“This is good for the humane society,” Nelson said. “Any dog that gets neutered is a good thing.”
Cathy Nelson (no relation), president of the Durango Kennel Club, said the organization is just learning about the injection option for neutering.
“It’s all kind of new,” Nelson said. “The most important thing for us is the safety of our dogs.”
Santi did her first neutering, of nine dogs two weeks ago, to monitor reactions. Five dogs were supplied by owners, four by the Aztec Animal Shelter. All the shelter dogs subsequently found homes. She will neuter 10 on Jan. 4. All procedures were done free of charge.
There was minimal swelling and no licking, Santi said.
During an interview, Santi took time to check Bubba, a 3-month-old Labrador retriever from Aztec Animal Shelter, adopted by Michael Meadows of Durango.
“He looks good,” Santi said.
Meadows agreed, saying Bubba hasn’t had any health problems and that he hasn’t noticed any behavioral aberrations.
Santi said the injection is safe. About 1.1 percent of dogs in the trials showed temporary side effects, including pain, licking of the scrotum, ulceration or infection. Other occasional reactions were vomiting, lethargy, loss of appetite and diarrhea.
A statement on the Ark Sciences website reported no long-term side effects. “We followed 40 dogs for more than two years and have data on many dogs for over five years. Since 1999, there have not been any reports of long-term side effects.”
Injecting Zeuterin is fast, less invasive and more economical than castration, Santi said. A sedative and the Zeuterin will cost $150 at Riverview Animal Hospital, compared with $175 for castration. Cost for the same procedure at other veterinary clinics varies, she said.
The injection is administered when the dogs are 3 to 10 months old, Santi said. The procedure, an injection of 0.1 to 0.2 milliliter of Zeuterin in each testicle, sterilizes a dog for life in 30 days.
Neutering doesn’t affect the ability of the testes to produce testosterone, which stimulates secondary sex characteristics in males, and inhibin, which balances the effects of testosterone.
“I decided the data on Zeuterin was compelling,” Santi said. “Neutering (via Zeuterin) reduces testosterone by about 50 percent, but the residual hormone protects dogs against disease, obesity, orthopedic problems, tears in the ACL, back problems and cancer.”
Castration removes the whole hormonal system, leaving no testosterone.
Cancer is common in pets, Santi said.
“We see cancer every day in dogs and cats,” Santi said. “If there is a way to reduce cancer, I’m on board because I hate cancer, and I want our pets to live long, heathy lives.”