Best Age to Spay Neuter
or Breed an English Mastiff

Spaying, neutering, and breeding may seem simple and streamlined, but the conflicting information about these methods can make it confusing for anyone. In fact, even the MCOA (Mastiff Club of America) had to revise its Code of Ethics several times, as experts gained a better understanding of this breed and the implications of these processes.

So, what's the best age to spay, neuter, or breed an English Mastiff? The rule of thumb in spaying and neutering is to wait for at least 18 to 24 months. It'll minimize the risks of developing degenerative or life-threatening diseases. The same rule applies for breeding, mainly for two reasons: to prevent stunting growth and development, and better trait selection.

Read on to learn more about spaying, neutering, and breeding an English Mastiff. This topic has more to it than just health issues and deserves an in-depth discussion—not an overly summarized, general answer. We'll cover everything in great detail, and hopefully, give you a more concrete answer when it comes to breeding your dogs. Read More Below...

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Basics of Spaying and Neutering an English Mastiff

Spaying and neutering may have various benefits, but doing it too early or too late has some serious health implications on your dog. So breeders or owners must understand the pros and cons of these methods before knowing the right age to do it.

Pros and Cons of Spaying an English Mastiff

Spaying isn't for every dog, and owner for that matter, because it'll depend on the overall health and age of your Mastiff. Here are some of the indisputable reasons why you should have your dog spayed:

  • It significantly reduces the risk of the most common malignant tumors among dogs—mammary tumors. However, it'll only work if the dog isn't older than 30 months (2.5 years).
  • Spayed dogs eliminate the risk of pyometra, a uterine infection that affects 23% and kills 1% of all intact female dogs.
  • It reduces the risk of developing uterine, cervical, and ovarian tumors.
  • It reduces the risk of perianal fistulas.

Everything sounds good, right? If that's the case, then why is it a huge issue for a lot of breeders? Well, that's because your dog can only gain from spaying if she's in great shape and at the right age. As a breeder, you'll have to weigh-in the pros and cons of spaying for your pet. So to help you make that decision, here are some perils associated with spaying:

  • Spaying a Mastiff, before full maturity, greatly increases the risk of developing osteosarcoma or bone cancer and splenic hemangiosarcoma.
  • It increases the risk of recessed vulva, vaginitis, recurring urinary tract infections, and urinary tract tumors.
  • It dramatically increases the risk of hypothyroidism, which can lead to various debilitating diseases.
  • 4% to 20% of spayed dogs suffer from spay incontinence or urinary incontinence. best age to spay, neuter or breed an English Mastiff


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Best Age to Spay an English Mastiff

Regardless of the breed, the rule of thumb is to wait for full maturity before you have your dog spayed. In the case of English Mastiff, their puppy stage can last anywhere from 18 to 24 months! That's the time that they need to develop their bones and other vital organs. 

It'll be overwhelming to keep track of her heat cycles and keep up with the physical and behavioral changes that come with it. But, the longer you can wait before spaying your dog, the better. Don't wait too long, though, because the health risks associated with spaying increases as soon as they reach 30 months (2.5 years) of age. best age to spay, neuter or breed an English Mastiff

Even if your dog reaches full maturity, you'll still have to weigh-in the pros and cons of spaying your pet. Sure, maturity can reduce the risks of developing intact-dog-related health issues. But, in some cases, spaying could amplify the risks of acquiring various spay-related diseases later in life.

Pros and Cons of Neutering an English Mastiff

Neutering is an obvious choice for a lot of Mastiff owners—imagine their size, humping on whatever they can find or come in contact with. Aside from eliminating this behavior, here are other compelling reasons why you should have your dog neutered: best age to spay, neuter or breed an English Mastiff

  • It eliminates the risk of dying from testicular cancer.
  • It reduces the risks of various non-cancerous prostate disorders.
  • It reduces the risk of perianal fistulas.
  • Although the data remains inconclusive, there have been studies that neutering can reduce the risk of developing diabetes.

We didn't include the obvious—unwanted puppies—because it's one of the main reasons why you'd want to neuter your dog. But before you decide on it, here are some problems that your dog might encounter:

  • Neutering a Mastiff, before full-maturity, greatly increases the risk of developing osteosarcoma or bone cancer and cardiac hemangiosarcoma.
  • It increases the risk of cognitive dysfunction or dog dementia.
  • It increases the risk of hypothyroidism, which can lead to various debilitating diseases.
  • It increases the risk of developing prostate and urinary tract cancers.

Best Age to Neuter an English Mastiff

Similar to spaying, the rule of thumb when neutering your dog is to wait until full maturity, which is 18 to 24 months for Mastiffs. It can be annoying because this dog will start humping on anything as early as six months old! You'll have to keep up with it for at least a year before it'll be safer to neuter your dog without stunting his growth and development. best age to spay, neuter or breed an English Mastiff

Other than getting rid of the obvious reasons, such as humping, marking territories, and fathering of unwanted puppies, the benefits that your dog can gain from neutering barely outweigh the risks. It's even worse if you have it before full maturity, so if you decide to neuter your dog, you'll have to wait for as long as you can to minimize the risks.

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Best Age to Breed an English Mastiff

The heat cycle for an English Mastiff can start as early as six months, but it's crucial to let it pass to preventing stunting her development. Most breeders agree that the second heat cycle is safe and ideal for "most" dogs—not for Mastiffs, though.

You see, most dogs will reach full-maturity after 12 months, but Mastiffs take a lot of time to mature, and that's where the confusion comes in. The best age to breed a Mastiff is during her third heat cycle, but the MCOA doesn't leave anything to chance. Here's a quote from its Code of Ethics, Section 2:

"I will not allow a bitch to be bred prior to her reaching twenty-two (22) months of age, nor shall any bitch be bred after her seventh (7th) birthday. A bitch will not be bred more than twice in any eighteen (18) month period unless she does not whelp a litter, the litter is stillborn, consists of a single (1) pup, or as a part of a veterinarians recommendation for treatment of pyometra. A bitch will have no more than four litters in her lifetime."

Twenty-two months is the ideal age to start breeding a Mastiff because that's when they're mature enough to give birth. Another reason why you'd want to wait for your dog's full maturity before breeding is because it helps you select the best genetics to pass on to the puppies.

It can be difficult to identify any hereditary traits that a dog may pass onto her offsprings while she's still in her puberty stage. If you wait for her full development, you'll get a better picture of the traits, health conditions, and temperament that she has. It'll be easier for you to select the traits that you want to breed and avoid passing any hereditary issues to her offspring.

Conclusion...

Spaying and neutering are important processes that can solve various issues with your dog. It includes the behavioral changes that occur in response to their breeding instincts. However, spayed or neutered dogs also show increased chances of developing other conditions when compared to intact dogs. So you'll have to weigh in on the pros and cons of both processes, together with your dog's overall health.

As for breeding your Mastiff, it would be best to let at least three to four heat cycles pass. It'll give you and your veterinarian enough time to assess her health condition, and decide whether she has the traits that you want your puppies to have. Twenty-two months old is also the safest age to breed without stunting or affecting her growth and development.

Here’s More Cool Information About English Mastiffs From These Pages On Our Site…


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  3. Best Age To Spay Neuter Or Breed An English Mastiff