JustOneMorePet

Every Pet Deserves A Good Home…

‘Zeutering’ offers dog sterilization in a ‘shot’

The Humane Society of San Bernardino is one agency offering the procedure; some experts dislike results

DAVID BAUMAN/The Press-Enterprise

Jeff Moder and Ashley Kinsey sit with Hercules, their 9-month-old pit bull mix, in their San Bernardino home on Sunday, August 25, 2013. The couple had the dog sterilized with a chemical injection as an alternative to surgical castration.

BY JANET ZIMMERMAN – The Press Enterprise  -  Published: September 01, 2013; 01:12 PM

The Humane Society of San Bernardino Valley has begun offering injections instead of surgery to neuter male dogs, a technique dismissed by some veterinarians who say it does little to control “unpopular behaviors.”

The new method, known as “zeutering,” uses zinc gluconate and arginine to sterilize male pups. The makers of Zeuterin say it is valuable for reducing pet overpopulation because it has fewer complications and a shorter recovery time than traditional sterilization.

But some animal experts complain that it costs about the same as surgery and doesn’t eliminate hormone-related behaviors such as aggression, marking and roaming.

About 200 veterinarians across the country, including four in the cities of San Bernardino and Riverside, have been trained and certified to use Zeuterin since it was approved by the Food and Drug Administration a year ago, said Don Cowan, spokesman for Ark Sciences in New York, the manufacturer.

The 30-minute procedure is geared toward dogs that are 3 to 10 months old. A dog with testicles larger than 1.24 inches wide would not be eligible, he said.

The zinc compound is injected into each testicle, killing the cells that produce sperm. The testicles shrink but remain visible — a plus for pet owners who want their dogs to look virile, Cowan said.

The most painful part of the procedure is the optional tattooing of a “Z” near the scrotum so people know the animal has been altered, he said. The information also can be registered with microchip databases.

“Many dog owners are understandably concerned about onlookers and ‘dog run’ friends giving them the evil eye, assuming their anatomically correct male dog is intact,” the Ark Sciences website says. “To address this concern, we are finishing up final designs on collar add-ons and fun T-shirts for sterilized but not castrated dogs to flaunt their special status.”

Appealing to owners who don’t want to change their dog’s appearance was the main reason the Humane Society in San Bernardino began offering chemical castration. Fifteen procedures have been performed there since June, compared to about 500 surgical castrations in the same period, spokeswoman Jill Henderson said.

“This is better than nothing, because this keeps the dogs from reproducing,” she said. More than 34,500 dogs were euthanized at shelters in San Bernardino and Riverside counties in 2011, according to state statistics.

EASY RECOVERY

Ashley Kinsey and Jeff Moder’s dog, Hercules, a 5-month-old pit bull-French Bordeaux mix, was among the first to have the procedure at the San Bernardino animal clinic.

Kinsey was worried about Hercules becoming fat and lazy without testosterone and she knew that a license for an unaltered dog in San Bernardino is an additional $55 per year. Moder just didn’t want him altered.

“I saw they were offering zeutering and I started looking into it because it sounded a lot better,” Kinsey said. “It was really easy for him to recover. He was hyper right away.”

Because the dog is under light sedation, the procedure offers a quicker recovery and avoids side effects from general anesthesia, Cowan said.

To try to control attacks on people and pets, Riverside County supervisors are considering an ordinance that would require pit bulls and pit bull mixes to be spayed or neutered. But injection-neutering may not be effective in curbing aggressive behavior, experts say.

Dr. Allan Drusys, chief veterinarian at Riverside County Department of Animal Services, is not a fan of the procedure. It is not performed at any of the agency’s three shelters.

His main complaint is that while Zeuterin does halt the production of sperm, it reduces testosterone by only 41 to 52 percent — leaving animals with hormone-driven behaviors.

“We’re talking about looking for love in all the wrong places, jumping fences and chasing after females in heat; and to some extent, aggression. A lot of these unpopular behaviors of male dogs are sexually modulated,” Drusys said.

Cowan said the issue of retaining testosterone in dogs is controversial and that more studies are needed to determine its effect on behavior.

COST DEBATED

Some veterinarians also take issue with the company’s claim that zeutering costs less than surgical sterilization.

The product itself may be less expensive, but there are added fees for the doctor, environmental disposal fees for the needles and other ancillary services, Drusys said.

The county charges $85 for canine neutering, plus pain medications, but there are often specials, underwritten by grants, that make it free or low cost, he said.

The Humane Society charges $54 for zeutering; traditional neutering costs $54 to $134, depending on the dog’s weight. At the nonprofit Animal Samaritans clinic in the Coachella Valley community of Thousand Palms, zeutering costs $125; surgical sterilization is $95 to $135.

Animal Samaritans began offering the service in June but has yet to have any takers, spokesman Tom Snyder said. The group offered Zeuterin training to area vets earlier this year.

The clinic has used the injections on some shelter dogs, but the results were not as good as expected, he said.

“We have discovered that it does not eradicate some aggression that is associated with high levels of testosterone,” Snyder said. “We can no longer use that as a selling point.”

September 3, 2013 Posted by | animal behavior, Animal or Pet Related Stories, Animal Related Education, animals, Dogs, Dogs, Just One More Pet, Pet Health, Pets, responsible pet ownership | , , , , , , , , , | 5 Comments

An Alternative to Surgery to Sterilize Male Dogs

Story at-a-glance

sterilized-dog

  • An injectable chemical sterilization drug will be available for use in the U.S. by the end of this year. It is currently FDA-approved only for dogs from 3 to 10 months, but the manufacturer believes it will be approved as safe for all dogs 3 months and older by the time it is released.
  • The drug, brand name Zeuterin, contains zinc gluconate neutralized by arginine. It acts as a spermicide and causes irreversible fibrosis of the testicles, which eventually atrophy and shrink in size, but remain visible.
  • Upon its initial release, Zeuterin will be made available primarily to shelters and spay-neuter clinics. The drug can only be sold to licensed veterinarians who have been trained in the injection procedure by the manufacturer.
  • The drug is highly effective at sterilizing male dogs with a single injection in each testicle. There are some side effects which seem primarily related to the injection technique.
  • It’s important to understand no sterilization procedure is completely risk-free, short or long-term. Once Zeuterin is widely available to private veterinary practitioners, we encourage dog owners to discuss with their vet the pros and cons of the procedure vs. traditional spaying or neutering.

By Dr. Becker

An injectable sterilization product for male dogs containing zinc gluconate neutralized with arginine is scheduled for release in the U.S. by the end of this year under the brand name Zeuterin ("zinc neutering"). The product is already in use in Bolivia, Columbia, Mexico and Panama under another name.

The drug is effective for permanent sterilization of male dogs at least three months of age. Zeuterin has been approved by the FDA for use in dogs three to ten months of age and can be obtained only by licensed veterinarians who have received training from the drug’s manufacturer, Ark Sciences, in how to perform the injections. The manufacturer believes the drug will be approved for use in dogs of any age over three months before the U.S. release date.

The drug functions as a spermicide and causes irreversible fibrosis of the testicles, which eventually atrophy and shrink in size, but remain visible. Dogs receiving the injection are tattooed in the groin area as proof they are sterile.

Product Launch Aimed at Shelters and Spay-Neuter Clinics Across the U.S.

Many shelters and spay-neuter facilities don’t have the recovery space for animals after sterilization surgery. For those organizations, Zeuterin should save time, money and space.

The injections are done on an outpatient basis, no anesthesia is involved, and dogs can be released relatively quickly after the procedure. Shelters and spay-neuter programs can then transfer some of the resources formerly committed to neutering male dogs toward spaying females and other outreach programs.

Proponents of Zeuterin believe it is unlikely individual veterinary practitioners will immediately embrace the sterilization drug, simply because they are already equipped and trained to do surgical spays and neuters. In addition, at this time Ark Sciences is training only a limited number of private veterinarians to inject Zeuterin.

Pet owners who want to have their male puppy chemically sterilized can add their names to a waiting list, which will at some point trigger Ark Sciences to send an offer to their vet to get certified to inject Zeuterin. According to Ark Sciences, the waiting list will be worked on a first-come first-served basis when the product becomes available.

It’s impossible to predict when Zeuterin might be widely available as an option for private vet practices and individual pet owners. Whenever that time comes, I think it’s important to understand the potential risks and benefits of this method of sterilizing male dogs.

Technology Approved by FDA in 2003

The formulation of zinc gluconate neutralized by arginine was actually approved by the FDA in 20031. That same year the drug was produced by Pet Healthcare International and distributed in the U.S. by Addison Laboratories under the name Neutersol.

According to Ark Sciences, Addison Labs overestimated the demand for the drug and created too much inventory. Excess inventory expired in two years, Pet Healthcare International went unpaid, and production shut down. Addison Labs and Pet Healthcare ended their relationship in 2005.

Ark Sciences subsequently acquired all rights to the Neutersol technology and has been distributing the product in Mexico and three other countries under the name Esterilsol for the last four years. They have used the drug extensively in Mexico in dogs three months and older to further evaluate its effectiveness as a sterilization agent, as well as to refine and improve the injection technique.

How the Drug Works as a Sterilization Agent

According to the Alliance for Contraception in Cats and Dogs (ACC&D) in their April 2012 Product Profile and Position Paper2 on Zeuterin:

As with any medical intervention, safety and effectiveness depend upon proper administration. The exact mechanism of action is not known. The following is based on a description provided by Ark Sciences. The product should be administered as an intratesticular injection into the center of the testicle via the dorsal cranial portion of testicle, parallel to the longitudinal axis. After injection the compound diffuses in all directions from the center of the testis. In the concentration used, zinc gluconate acts as a spermicide and destroys spermatozoa in all stages of development and maturation. It results in permanent and irreversible fibrosis in the seminiferous tubules, rete testis and epididymis. This produces a reduction in the size and texture of the testicles and permanent sterilization. Testosterone production is reduced by 41-52%, and the endocrine feedback system remains intact. Zinc gluconate is absorbed and metabolized by the body within 72 hours after the injection.

Also, from the Ark Sciences FAQ web page3:

How is testosterone lowered by Zinc Gluconate neutralized with Arginine?

The dosage and concentration is designed to ensure Leydig Cells in the interstitial space of the testes survive the procedure. Stimulated by Luteinizing Hormone (LH) produced in the pituitary gland, the Leydig Cells continue to support testosterone-related metabolic activity and growth. In the absence of spermatogenesis, Sertoli cells stop communicating the need for testosterone to mature sperm cells. The pituitary gland detects this lowered demand and lowers the LH levels. Since LH levels determine how much testosterone is produced by the Leydig cells, overall testosterone levels are reduced by 41-52% for all dogs permanently.

Zeuterin Adverse Reactions

The 2003 FDA drug approval document includes a study of 270 male puppies injected with the chemical sterilant. The puppies were a combination of shelter animals and family pets.

The following reactions were noted:

Reactions Upon Injection
Local Reactions

Reaction
Dogs Affected
Reaction
Dogs Affected

Vocalization
6
Scrotal Pain
17

Kicking
1
Scrotal Irritation
3

Biting and Licking
2

General Reactions
Scrotal Swelling
2

Reaction
Dogs Affected
Scrotal Dermatitis
2

Leukocytosis
2
Scrotal Ulceration
1

Neutrophilia
17
Scrotal Infection
1

Vomiting
12
Dry Scrotal Skin
1

Anorexia
11
Scrotal Bruising
1

Lethargy
6
Preputial Swelling
1

Diarrhea
5
Scrotal Sore
1

Another zinc gluconate sterilization study was done in the Galápagos Islands and published in 2008. It was conducted in a cooperative effort by the University of Florida, the ASPCA, and Animal Balance of San Francisco, and titled "Comparison of intratesticular injection of zinc gluconate versus surgical castration to sterilize male dogs."4 The following observation was made by the researchers:

Although the complication rate was similar for surgical and zinc-gluconate castration, the zinc-gluconate reactions were more severe. Surgical wound complications were treated by superficial wound debridement and resuturing. In contrast, zinc-gluconate reactions required antimicrobial treatment, orchiectomy, and extensive surgical debridement and reconstruction, including scrotal ablation in 2 dogs. These reactions occurred following administration by both experienced and novice individuals. All dogs made a full recovery following treatment of zinc-gluconate reactions and incisional dehiscences.

The authors of this study determined that proper injection technique is critical because injection or leakage into surrounding tissues can result in severe tissue damage. And while scrotal swelling and tenderness are common in the first days after injection, a more serious reaction is the development of scrotal ulcers or draining tracts in the scrotal or preputial area. The self-trauma that follows can be severe.

The researchers also observed that lesions aren’t always restricted to the injection site, which could indicate the solution may spread beyond the target area.

Long-Term Side Effects

According to Ark Sciences, since 1999 when the initial clinical studies were performed, there have been no reports of long-term side effects.

I would just add here that whenever we manipulate nature sufficiently to stop procreation, there WILL be long-term side effects. This is true for spay/neuter, and any other method. We are just beginning to understand the lifelong implications of surgical removal of ovaries and testicles, yet spaying and neutering of cats and dogs has been a common practice for decades.

I’m certainly not against the sterilization of pets. I’m a proponent of assessing the risks and benefits of everything we do as guardians of the animals in our care.

You can read more about Zeuterin on the Ark Sciences FAQ page as well as the other documents linked in the references, below.

Once the product is widely available to private veterinary practitioners, if you’re considering it, I recommend talking with your vet about the pros and cons of the procedure for your own dog.

Related:

Pet Sterilization Laws Raise Health Concerns

Caring for Pets Before, During and After Anesthesia

New methods of pet ‘pampering’ include fake testicles and facials

August 17, 2012 Posted by | Adopt Just One More Pet, Animal or Pet Related Stories, Animal Related Education, Dogs, Dogs, If Animlas Could Talk..., Just One More Pet, Man's Best Friend, Pet Friendship and Love, Pet Health, Pets, responsible pet ownership | , , , , , , , , , , , , | 4 Comments