Whether a male dog can impregnate a female dog after being neutered is an important question considering that the main purpose of neutering is preventing the numbers of unwanted litters. Although dogs aren't as prolific as cats, their numbers can increase dramatically if we would allow nature to run its course. For instance, consider that just one intact female dog and her descendants can potentially produce as many as 67,000 dogs in just six years! In this article, Dr. Ivana Crnec explains whether a male dog can impregnate a female dog after being neutered.
Benefits of Neutering Dogs
We are all very well aware of the benefits of having our dogs fixed. Whether talking about spaying or neutering, the advantages are beyond worthy – from prolonging the lifespan, and reducing the risk of reproductive issues, to better behavior and enhanced training responsiveness. However, the most important part of having our dogs fixed is controlling the overpopulation and consequently reducing the number of homeless and stray dogs.
Generally speaking, neutering has both medical and behavioral advantages. Neutering not only prolongs the lifespan, but it also enhances the quality of life. For example, neutered dogs are less likely to get seriously injured in dog fights. Additionally, neutered dogs are usually more responsive to their owner’s commands and they are easier when it comes to obedience training. As a result, the risks from roaming behavior are, if not eliminated, at least significantly reduced.
Neutering is a surgical procedure. Alternatively, there are other birth control methods such as anti-fertility vaccines and hormone drugs. However, those methods are all under investigation as yet none have been found to be both safe and reliable.
On a long-term basis, neutering can safely be performed on dogs as young as seven weeks of age. However, some vets have personal and unwarranted reservations about neutering before a dog reaches sexual maturity.
Understanding The Neutering Procedure
As previously stated, neutering is a surgical procedure. Although more commonly known as castration, its exact scientific or medical term is orchiectomy. The procedure got its name from the Latin words"orkhi," which means testicle, and "ectomy" which means cutting.
Simply put, neutering, as a surgical procedure is a routine operation performed under general anesthesia. In a nutshell, the procedure involves removing both testes. Once the operating field is clipped and disinfected, two parallel incisions are made on the scrotal sac (in front of each testicle). Then the testicles are removed while leaving the scrotal sac intact.
Alternatively, the incision can be made above the scrotal sac (pre-scrotal method). In that case, both testicles are removed from the same incision and then the incision’s layers are properly sutured. During the post-op period, neutered dogs require suitable pain killers.
Ultimately, the removal of the testes results in: 1) Stopping the process of sperm production and 2) reducing the rate of male hormones (testosterone) production.
How does neutering changes male dogs?vCastration ultimately results in loss of many male characteristics such as marking with urine, aggression towards other males and straying after female dogs in heat. It also stops young dogs from attempting to mount people’s legs. Simply put, castration prevents all forms of unwanted sexual behavior (roaming, attraction to females, humping, mounting and masturbating).
However, it is a popular misconception that castration calms down easily excitable dogs. In fact, castration influences only the hormone-driven behaviors. Those behaviors do not magically stop after the procedure. Instead they slowly diminish over a period of several weeks.
It should be well-noted that castrating dogs does not prevent some rare forms of prostate cancer, but it does reduce the risk of the more common prostatic hyperplasia and testicular tumors. Additionally, castration reduces the risk of developing perianal tumors and hernias.
Can a Male Dog Impregnate a Dog After Being Neutered?
Well, this is a rather tricky question. A few years ago, I neutered a 4-year old Pekingese dog named Pako. The surgery went smoothly and Pako was discharged and sent to spend the night at home. The following morning, Pako’s mom called to tell me that our recently fixed Pako is now tied with the neighbor’s Maltese dog.
This old case of mine pretty much answers the above stated question. Simply put, yes, castrated dogs can still have sex. Theoretically and practically speaking, a castrated dog can get aroused, experience an erection and tie with a female in heat.
The statement that neutered dogs can still be sexually driven gives place for proposing another, even more important question – can a neutered dog successfully impregnate a receptive female? The answer to this question is even trickier and it depends on how long ago was the dog neutered.
Generally speaking, a recently fixed dog can still breed a receptive female. This is because the testicles are not the only place where active sperm is stored. In fact, viable sperm can be found in several storage places of the male reproductive system. Theoretically speaking, the sperm may survive in those storage places for as long as 1 month. Practically speaking, the sperm remains viable for several days. This phenomenon is known as "dormant sperm."
From the above stated, it is safe to assume that, if it has been less than a month since the dog was castrated, it is still capable of breeding. On the other hand, if it has been more than a month since the neutering procedure, the dog can have sex, but it will not be able to impregnate its partner. All in all, the entire adventure will not result with a pregnancy.
With that being explained, it should be emphasized that not all castrated dogs will want to have sex. When the testosterone levels fall down, the dog’s libido decreases as well. However, certain dogs' libido seems unaltered by the neutering procedure.
The take home message would be that, in terms of having babies, neutered dogs can have safe sex. However, the sex is not safe in terms of transmitting certain infectious diseases.
How Long Should Neutered Dogs be Kept Away From Females in Heat?
In castrated males, the levels of testosterone start falling down within eight hours. However, certain amounts of testosterone remain in the system for several months. Another thing that remains in the system is the already created sperm. Namely, the sperm that was created and stored in the reproductive tract may remain active and even viable for as up to 1 month. In some literature, it is stated that neutered dogs can be fertile for as much as 6 weeks post neutering.
One month after the neutering, the stored sperm in no longer viable, and since the testicles are removed, the storage cannot be replenished. Additionally, one month after the procedure, the testosterone levels significantly drop which decreases the sex drive thus reducing the odds of having your castrated male breed with a female.
About the Author
Dr. Ivana Crnec is a graduate of the University Sv. Kliment Ohridski’s Faculty of Veterinary Medicine in Bitola, Republic of Macedonia.
She currently practices as a veterinarian in Bitola and is completing her postgraduate studies in the Pathology of Domestic Carnivores at the Faculty of Veterinary Medicine in Zagreb, Croatia.
Ivana’s research has been published in international journals, and she regularly attends international veterinary conferences.