Castration by implant in male dog: advantages and disadvantages

In France, about 30% of male dogs are neutered. For about ten years, castration of the dog by implant has been an interesting alternative to surgical castration. Safe and effective, it does not require general anesthesia. It also has the advantage of being reversible.

Are you hesitant to sterilize your partner? Removing the testicles is actually a definite act that can scare the masters. And if you opt for sterilization through a dog implant? This technique can be occasional, for example to “test” the effect of castration on your animal, or repeated for permanent contraception. But, by the way, how does an implant work in dogs?

What is dog sterilization by implant?

For about 13 years, veterinarians have had implants to sterilize male dogs.

  • What is an implant?

The implant is a small cylinder (1 to 2.5 cm in length) composed of biologically compatible lipids that are implanted under the skin. It will then release medication within a few weeks. In the case of dog implants, it is deslorelin.

Implant contraceptives are also used in human medicine, in women.

  • How does the implant work in the dog?

Deslorelin has the action of rapidly decreasing testosterone production resulting in sterilization in the dog (cessation of sperm production).

As a result of this decrease in testosterone, the size of the testicles decreases and some sex-related characteristics disappear (urinary marking, overlapping, etc.).

The average duration of implant operation is 6 to 12 months, or longer depending on the dose and the dog. In small dogs of the Chihuahua or Spitz breed, the action of the implant is usually higher. At the end of this period of time, the animal can be replanted, spayed by surgery or returned to its former life!

  • How to put an implant in dogs?

The implant is injected under the skin, between the shoulder blades, using a special syringe equipped with a needle of sufficient gauge to allow the passage of the cylinder. To be implanted, the dog must be pubescent (between 6 and 15 months of age depending on the breed).

  • What are the side effects of implant castration in dogs?

Inflammation of the injection site is sometimes noticed in the days after implantation of the device. A slight increase in libido can also be observed, but amazing!

Hair loss or clothing changes related to low testosterone are possible, but rare. Like surgical sterilization, weight gain remains the most common side effect. This risk is managed with the help of an appropriate plan.

Castration by implant versus surgical castration of the dog?

Castration, whether surgical or chemical, can be introduced for several reasons:

  • Avoid unwanted pregnancies when the man and woman are together
  • Cure some behavioral problems in male dogs such as urine marking, overlap, intra-specific aggression, runaway, excitement due to female dogs in the heat of the neighborhood
  • Medical: tumor of the testicle or circumanal glands, prostate hyperplasia …

Surgical castration involves the removal of the testicles. It requires anesthesia and, by nature, is irreversible. This so -called convenience operation is very well trained by veterinarians and accidents are rare.

The implant has the advantages of ease of placement (a simple injection without anesthesia) and novelty. Note that the trocar for this injection is still of good caliber and this work can be momentarily painful, especially in small dogs. After 6 months, the injection can be changed, then annually.

Placing a contraceptive implant for dogs can also be a way to realize the effects of castration on your animal before choosing permanent surgery. The predictivity of this test is very good. For example, if you want to neuter your dog due to running, you can choose an implant first. If he continues to run away, he doesn’t have to be castrated, nothing changes! Similarly, if your Labrador gains a lot of weight with his implant, it is likely to be the same after castration, which can be a problem with his joints. In this case, it is better to reject castration, or, if not possible, establish a draconian diet.

dog poaching


In operation





During injection

On waking a few days after surgery, but controlled by painkillers


Yes (with exceptions, especially for small varieties)


Weight gain

It is possible, but reversible

Possible (always)


115 to 200 euros (excluding consultation)

130 to 300 euros depending on weight

When will the female dog be sterilized through the implant?

And the woman of all this? Currently, implants are limited to pubertal male dogs. Several studies have been done on adult female dogs, but there is no certainty. In fact, implant placement causes heat in the days after implantation in 100% of female dogs. In addition, annoying side effects, such as ovarian cysts, onset of lactation or uterine infection, have been reported. An attractive alternative to ovariectomy, sterilization by implant in the female dog is not yet on the agenda.

Dr. Isabelle Vixege


Leave a Comment