There may be many reasons for dogs to give birth to puppies with deformities. If a dog carries a certain genetic mutation, it may cause deformities in the puppies. This genetic mutation may be inherited from the parent dog, or it may result from a mutation.

In addition, it may be that the medication used when the female dog is pregnant may easily affect the deformity of the puppies. Some details were not paid attention to when the female dog was pregnant, resulting in poor development and deformed puppies.