Like most responsible dog owners, Crystal Ondo and Edward Wenger took their English bulldog puppy Tanqueray to the vet to get neutered when he was 6 months old.

"It was just really sad," said Ondo, a law student in Boston. "Surgery is just sad in general, and then he came out with the cone on his head. I felt really bad for him."

Tanqueray, or Tanq, is now 3 years old. He is small, puppyish and loved by his owners -- so much so that they wish they could have more of him.

"It would be great to have little Tanqs running around," said Wenger. "I'm not like most guys…it was more about his having to go into surgery."

In the future, dog owners who decide they want to breed their dogs later in life may have an option -- a removable contraceptive implant that halts testosterone and sperm production for months at a time.

The best part is it doesn't require the removal of the testicles.

The device, described in the current issue of New Scientist magazine, is called Suprelorin. It is currently available in Australia and New Zealand. Similar to a microchip, it is implanted under the skin between the shoulders.

There it slowly releases deslorelin, a hormone similar to those used to treat human prostate cancer. The hormone prevents the production of sex hormones, and the device biodegrades over time.

But preserving puppy-making potential has its price. Each implant costs between $52 and $77 and must be replaced every six months -- though Peptech, the Australian biotechnology company that makes the device, is now working on a one-year version.

Still, Suprelorin is expected to gain approval for use in the European Union in a matter of weeks, and steps are being taken to enable the drug to be sold in the United States.