Bad breeding is a term used to describe negative genetic traits passed down through generations. It is often used to refer to animals, but can also be used to describe people. Synonyms for bad breeding include defective genetics, poor bloodlines, inferior breeding, and flawed ancestry. Other phrases that are often used to convey this concept include "inferior stock," "degenerate lineage," and "poor breeding program." Bad breeding can result in a host of health and behavioral problems, including physical deformities, aggression, and poor temperament. It is important for breeders and pet owners to be aware of these issues and take steps to prevent them from being passed on to future generations.