When Do Male Dogs Become Sexually Active?

Puppies truly do grow up quickly. In fact, before you know it, your dog will be 6 months old and sexually mature. That's why it's so important to have your dog neutered to prevent him from becoming sexually active. Neutering is important because if you're the owner of an unfixed, physically mature male dog who regularly has access to female dogs, then the concept of sexual activity may indeed be a reality for him. Once a dog hits the age of reproductive maturity, he can begin mating at any given time, and that can result in litters of unwanted puppies and upset neighbors.

Most male dogs often attain reproductive maturity and capability when they are approximately 6 to 9 months old. However, large and giant dog breeds generally reach maturity more slowly than smaller dog breeds. This means that your larger-size dog may not reach sexual maturity until he is around 12 to 18 months old.

While some small-breed male dogs can impregnate a female dog when they are as young as 5 months old, most dogs are considered most fertile between the ages of 12 to 15 months. During this time, they will also be the most aggressive, especially to other male dogs. This can lead to embarrassing and potentially dangerous encounters in dog parks and during walks. For example, if you encounter another male dog while outdoors, your dog may either try to hump the other dog or fight with him.

As soon as a male dog is sexually mature, he is essentially ready for the mating process and sexual activity. There is no wait necessary. When a male dog is physically mature, many of his behavioral patterns are suddenly driven by sexual hormones, even if a female dog in heat is not present.

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Unlike female dogs, who are only ready to mate during their heat cycles, males are basically available at any time. This also means that they are not only more aggressive but also desperate to roam throughout the entire year too, turning them into furry escape artists with behavioral issues who are on the search for female dogs with whom to mate.

If your pooch is ready and willing to become sexually active, he will probably make it very obvious to you and to everyone in your neighborhood with his excessive barking. Some key signs of hormonally influenced male dog behavior include:

• Urine spraying in the home
• Increased vocalizations
• Humping and mounting behaviors
• Aggression and irritability
• Incessant attempts to run away from your home and go outdoors

While female dogs exhibit some of these same behaviors when they're in the midst of their heat cycles, also known as estrus, a male dog will exhibit these behaviors all year round. If an intact male dog has close access to an intact female dog in season, then the chances of sexual activity occurring are very, very high, so be careful and keep your dog indoors or within a secure, fenced yard.

Neutering a male dog at a young age may be beneficial in that it may halt any unpleasant mating behaviors and any sexual activity that comes from it. While some veterinarians recommend getting a male dog neutered before he reaches sexual maturity, others recommend waiting until he is between 7 and 15 months old.

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Speak to your veterinarian regarding the safest and most appropriate time to neuter your specific pup. That's because neutering your dog too early may cause orthopedic issues, especially in some larger and giant dog breeds. Most importantly, remember that neutered dogs are unable to reproduce and contribute to your neighborhood's canine overpopulation issues.