The Reading Corner

Neutering Your Dog

Karen Tobias, Veterinarian, University of Tennessee


Is early age neutering good for your dog? There are benefits, complications associated with early age neutering

Veterinarians and many pet owners recognize the benefits of spaying or castrating their dogs. Neutering animals reduces the risk of certain types of diseases, such as mammary tumors, uterine infections, and prostate swelling, and eliminates the chance of unplanned litters. Additionally, annoying behaviors associated with an overabundance of "teenage sex hormones" are hopefully avoided by removing the hormonal source — the ovaries or testicles.

Early age neuters are being performed at many humane shelters in dogs as young as 7 weeks of age. Studies have shown dogs neutered at this age have faster anesthetic recoveries and fewer operative complications compared to animals neutered at 7 months of age. Additionally, no adverse medical or behavioral complications have been noted when the animals were evaluated up to a year after surgery.

The primary concern of early age neutering, however, is whether there are any long-term negative effects that may impact the dog's health and behavior as it reaches middle age.

In a recent study by Dr. Spain from Cornell University, owners of 1,842 dogs were surveyed 4 months to 11 years after their adopted pets had been neutered to see if the dog's age at the time of surgery had any effect on the pet's well-being. Dr. Spain and his colleagues identified benefits as well as disadvantages with neutering very young animals.

Most of the benefits of early-age neutering were behavioral. Dogs that were spayed or castrated at less than 5.5 months of age were much more likely to remain a permanent part of their adopted families. Additionally, dogs neutered at a young age were less likely to roam or to escape from their homes or yards. Other studies have shown that early age castration can also reduce aggression in male dogs.

Unfortunately, early-age neutering was also associated with several medical problems.

Dr. Spain and colleagues found that male and female dogs neutered at a younger age had an increased risk of developing parvovirus soon after the surgery. Also, they were more likely to develop signs of hip arthritis as they got older. This may be because dogs neutered at a young age tend to have longer legs, possibly causing some joint problems as they get older. Female dogs had an increased risk of bladder infections and urinary incontinence, especially if they were spayed before 3 months of age.

So what is the best time to neuter your pet?

No one knows the perfect age for neutering pets, so recommendations are usually based on the individual and the breed. Male dogs are less likely to suffer long-term effects with early age neutering, and those with dominant or aggressive temperaments should probably be castrated at 4 to 6 months of age before they are sexually active.

Female dogs are more likely to have chronic problems if neutered at a very young age, but should be spayed at 6-12 months of age, before their first heat cycle, to reduce the risk of mammary tumor development.


About Karen Tobias

Dr. Tobias is a full professor at the University of Tennessee College of Veterinary Medicine and a Diplomate of the American College of Veterinary Surgeons.

Dr. Tobias specializes in soft tissue surgery, and is currently the president of the Society of Veterinary Soft Tissue Surgery.

She resides in Knoxville, Tennessee with her husband and two children.