Spay and Neuter Information
Recent studies have shown that neutering (refers to as spaying also) can have an adverse effect on the health of a dog. To further delve into this latest information, a team of researchers at UC Davis recently examined the veterinary records of 759 Golden Retrievers for hip dysplasia, cranial cruciate ligament tear, lymphosarcoma, hemangiosarcoma, and mast cell tumor. The dogs were grouped as intact, neutered before 12 months of age, or neutered after 12 months of age.
The study revealed that the disease rates were significantly higher in both males and females that were neutered both before and after 12 months of age. Early neutering was associated with an increased incidence of hip dysplasia, cranial cruciate ligament tear, and lymphosarcoma in males and of cranial cruciate ligament tear in females. Neutering after 12 months of age was associated with an increased risk of mast cell tumors and hemangiosarcoma in females.
The most notable results from this study include a doubled risk of hip dysplasia among dogs neutered before 12 months of age and an increased risk of mast cell tumors and hemangiosarcoma in dogs neutered after 12 months. Previous studies reported only a 17% increase in the risk of hip dysplasia in neutered dogs and this is the first study to report an increased risk of cancer in dogs neutered later.
Of the five diseases measured, the study reported that:
- There were no cases of cranial cruciate ligament rupture diagnosed in intact males or females, but in early neutered males and females the occurrences were 5% and 8%, respectively
- Almost 10% of early-neutered males were diagnosed with lymphosarcoma, three times more than intact males
- The percentage of hemangiosarcoma cases in late-neutered females (about 8%) was four times more than intact and early-neutered females
- There were no cases of mast cell tumors in intact females, but the occurrence was nearly 6% in late-neutered females
- Of early-neutered males, 10% were diagnosed with hip dysplasia, double the occurrence in intact males.