Excerpt below is a study on when to sexually alter mixed breed dogs, based on their sizes.
“One major finding from the present study is that despite the dogs being of mixed breeds, there was uniformity in the relationship of body weight and association of neutering with increased risks of joint disorders. The cutoff of 20 kg /45 Lbs, where dogs above this point are significantly at risk for joint disorders, but those below this cutoff are not of significant increased risk, offers those adopting puppies, and wishing to neuter, some useful guidelines for ages of neutering with regard to avoiding the increased risk of painful and disabling joint disorders.
There was no clear picture with the cancers followed, undoubtedly reflecting the diversity of breeds involved in mixed breed dogs and the breed-specific differences with regard to vulnerability to different cancers.
This study focuses primarily on dogs going up through their middle-age years, and presents extensive data on diseases having early onsets, prior to dogs’ elderly ages. A limitation is that the study has little data going into the second decade of canine life when diseases such as mammary cancer become more frequent.
For those adopting a mixed breed puppy from a shelter or other source, the data in this study suggest that the risks of a joint disorder following early neutering can be predicted on the basis of the dog’s body weight. Those that are expected to reach at least 20 kg /44 lbs as adults have a significantly increased risk of one or more joint disorders that is up to 20% above the level of intact dogs.
The guidelines for age of neutering are offered in the Results Section in the article. If the mixed breed puppy is partially of an identifiable breed, such as Labrador Retriever, one could check the breed for cancers as well as joint disorders for guidance regarding the age for neutering. Pet owners and veterinarians can consider this information when making decisions or recommendations regarding the age for neutering a dog that will be in a specific adult weight category.”
Read Study here. This study references many other studies on cancer and joint issues in alter dogs.
List of studies on altering dogs
List of facts related to dogs who are Altered by Dr Odette Suter DVM
Overview of health issues with altered dogs: by Dr Karen Becker DVM
Video with Dr Becker talking about altering dogs:
UC Davis study on Shepherds who are sexual altered.
UC Davis study on Retrievers who are sexually altered
1) Charts and exact number of dogs in UC Davis study of Retrievers who are sexually altered.
2) Charts and exact number of dogs in UC Davis study of Retrievers who are sexually altered.
Study showing increased hip dysplasia in dogs sexually altered prior to 12 months old:
Joint disease and dogs who are sexually altered
Overview of multiple reasons early sexual altering harms dogs:
Determining the best age to sexually alter a dog