When to Spay or Neuter Your Dog: Breed Specifics
For decades, vets said "fix them at 6 months." New UC Davis studies have changed the game. Early neutering in large dogs is linked to joint issues and cancer.
The Growth Plate Factor
Sex hormones (Testosterone/Estrogen) tell the bones when to stop growing.
- Early Neuter: The bones grow longer than intended. This changes the joint angles.
- Result: Higher risk of Hip Dysplasia and CCL tears.
Small Breeds (Under 20lbs)
- Recommendation: 6-9 Months.
- Why: They finish growing early. There is no benefit to waiting. Poodles, Chihuahuas, Terriers.
Large Breeds (Over 50lbs)
- Recommendation: 12-18 Months.
- Why: Retrievers, Shepherds, and Rottweilers need hormones to close their growth plates properly.
- Study: Golden Retrievers neutered early were 2x more likely to get Bone Cancer or Lymphoma.
The Mammary Cancer Risk
For females, every "Heat Cycle" increases the risk of Mammary Cancer.
- Spay before 1st Heat: 0.5% risk.
- Spay after 2nd Heat: 26% risk.
- The Dilemma: You have to balance Joint Health (wait) vs Cancer Risk (do it early). Talk to your vet about your specific breed.