Should I get my pet neutered or spayed? When should I get my pet neutered or spayed? All good questions when getting a puppy, kitten or rescuing an older pet.
Our Recommendations for Spay/Neuter:
It has long been known that spaying a female dog or cat before their first heat results in almost zero occurrence of mammary tumors. After the first heat in the dog, the risk rises to about 8%, and after the second heat continues to rise to about 25% for mammary tumors. In the dog, 50% of mammary tumors are cancerous, and the other 50% are benign. In the cat, 90% are cancerous. In the male, the incidence of prostate cancer is very low, with neutering making no difference in the risk. Neutering also eliminates the risk of testicular cancer and decreases the risk for perineal hernias/tumors and unwanted male behaviors.
More recently, there is growing evidence that early spaying and neutering may actually increase the incidence of other highly malignant cancers, such as lymphoma, hemangiosarcoma, and osteosarcoma later in life in certain breeds.
Early spaying and neutering may also alter the growth of bones and joints predisposing to hip, elbow, and stifle disease in certain breeds.
With these facts in mind, we propose the following recommendations:
Male dogs: Wait until at least one year of age before neutering, preferably longer, perhaps only if testicular tumors develop or prostate problems later in life. Exceptions are aggression, inappropriate house-soiling or owner preference.
Male cats: If possible, wait until at least one year of age unless spraying, aggression or outdoor cats (decrease roaming and fighting, eliminate unwanted pregnancies)
Female dogs: Weigh the risks of increased mammary cancer versus better growth and less chance of other malignancies. A reasonable compromise might be to spay after the first heat and before the second, at around 1 year of age.
Female cats: Since mammary tumors are almost always cancerous, we still recommend spaying before the first heat, at around 6-7 months of age.