Update: There actually was a chicken that survived with his head cut off. From Fruita, Colorado, Mike lived for 18 monthes until he choked on some food. Find out how he survived at Mike The Headless Chicken. And change your opinion about the question above.
In purebred dogs, overbite and underbite are considered problems and aren't good for your chances of winning if you want to get a blue ribbon. This is when either the upper jaw and teeth stick out too far, or vice versa.
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