Researchers at the University of California Davis School of Veterinary Medicine have found that early spay/neuter in heavier mixed breed dogs can lead to joint problems later in life.

Specifically, the study found that mixed breed dogs with an adult weight of 44 pounds or heavier had a higher risk level for one or more joint disorders if they were neutered before 1 year of age.  Dogs with an adult weight of 43 pounds or less were found to have no increased risk.

An article on the study published by UC Davis notes that the standard age for canine spay/neuter in the US and Europe is 6 months.

The researchers chose to study mixed breed dogs because most dogs are mixed breeds.  The joint diseases examined included hip and elbow dysplasia and cranial cruciate ligament tears (knee injury).

The dogs studied were broken down into 5 different weight categories.  They found that in heavier dogs, the risk for joint injury increased by 4% in dogs neutered before 1 year of age.

The researchers note that a study that suggests late spay/neuter is good for certain dogs can be controversial.

Animal shelters and rescue organizations tend to have policies that require the spay/neuter of young puppies before they are put up for adoption.  “With mixed breeds it may be difficult to determine just how big the dog will become if you don’t know anything about the dog’s parents,” said one of the researchers.

The late spay/neuter of large dogs can also have implications in the service dog field.  “Joint disorders can shorten a dog’s useful working life and impact its role as a family member,” say the researchers.

Previous research has focused on the relationship between early neutering and joint disease in purebred dogs like German Shepherds and Labrador and Golden Retrievers.  This study on mixed breeds suggests that size can be as important a factor as breed.

Interested in learning more?  You can read the full text of the study, published in Frontiers in Veterinary Science, HERE.

Spay/neuter—even at a later age for larger size dogs—is still important to the overall health of your pet.  To read about the many health benefits of spay/neuter in dogs and cats, check out our blog article HERE.