The lifespan of a dog is between 10-15 years. When a female dog reaches 8 years old, her body’s metabolism slows down and the functions of various organs in her body decline, so she cannot give birth to puppies. Giving birth to puppies at this age will cause the female dog’s body nutrition to deteriorate. A large amount of loss is difficult to replenish and restore to the past, so puppies cannot be regenerated. Owners need to pay more attention to the female dog's estrus period to avoid mating and pregnancy.