Spaying a female dog eliminates the messiness associated with the heat cycle. Spaying helps prevent uterine infections and breast tumors, which are malignant or cancerous in about 50 percent of dogs and 90 percent of cats. Spaying your pet before her first heat offers the best protection from these diseases.
Neutering of male dogs and cats can prevent certain undesirable sexual behaviors, such as urine marking, humping, male aggression and the urge to roam. Neutering your male companion can also help prevent testicular cancer and other prostate problems.