Heads up, dog parents: bigger mixed-breed dogs are bound to have joint problems if neutered or spayed early, a new study from researchers at the University of California, Davis revealed.

At the most considerable risk are mixed-breed dogs that weigh more than 44 pounds, and were neutered below the age of one, the findings, which was published in the journal Frontiers in Veterinary Science, indicate.

The good news is, dogs weighing 43 pounds or below had no joint risk problems.

READ: When Is the Right Time to Neuter Your Dog? Recent Study Answers the Question

Joint Disorders in Neutered vs. Intact Dogs

The study reviewed and analyzed data of thousands of dogs for the past fifteen years at UC Davis Veterinary Medical Teaching Hospital.

The study team analyzed the common joint disorders in dogs, namely, cranial cruciate ligament tears, hip dysplasia, elbow dysplasia, knee injury, and correlated it to five weight categories.

The risks of mixed-breed dogs developing cancers based on weight were also examined. The research team found no increased risk of developing cancer regardless of the weight range compared to intact dogs.

The risk of having joint disorders for neutered more massive dogs could be a few times higher than dogs left intact. Female dogs weighing more than 43 pounds, for example tremendously increased the risk of having joint problems from 4 percent for intact dogs to 10-12 percent for dogs that have been spayed before reaching the age of one.

READ ALSO: Saving Giant Panda at the Expense of Leopards, Snow Leopards, Wolves, and Asian Wild Dog

A Review of Neutering Policies

In the US and Europe, dogs are commonly neutered by six months of age. One author of the study, Lynette Hart, admits that the investigation poses "unique challenges." Puppies, for example, are adapted from a shelter. This poses a problem as mixed -breeds, which are common in a shelter, may be challenging to determine how big the dog will become if there is no information from the dog's parents.

Humane society organizations, dog breeders, and shelters typically require neutering before adoption. Based on the findings of this study, authors suggest that neutering policies should be reviewed and appropriately revised and consider revising their standard age of neutering to more than a year for dogs that will grow bigger.

Significance of the Study Especially for Pet Owners

Hart said that this study is particularly relevant to people or organizations that are raising service dogs and thus must be given serious consideration.

"Joint disorders can shorten a dog's useful working life and impact its role as a family member," Hart said.

A previous study from UC Davis researchers also points that the vulnerability to cancers and joint disorders to dogs neutered or spayed within the first year would also depend on the breed.

The Great Danes and Irish Wolfhounds, two giant breeds, for example, had no risk of joint disorders when neutered at any age.

These two recent studies suggest that neutering the dog must be given careful consideration by the pet owner and matter should be discussed with their veterinarians.

As Benjamin Hart, one of the authors of the study put it, "we think it's the decision of the pet owner, in consultation with their veterinarian, not society's expectations that should dictate when to neuter."