#4 English Bulldog
The English bulldog has become very unhealthy and bulky. Because of their large body size, it has become difficult for them to procreate or to do anything else.
The dachshund’s legs have become shorter which makes the trunk to touch the ground. Their necks and backs have become taller which makes them prone to inter vertebral disc disease.
#6 German Shepherd
The German Shepherds were stronger earlier but now are considered one of the most ruined dog breeds. Their size is bigger in contrast to their capability.
#7 Saint Bernard
The dogs have overgrown in size while their face remains unchanged. These dogs are no more used as working dogs as they easily overheat.
The astonishing results of dog breeding can be seen apparently in not only the dog breeds, but in other animals such as cats, monkeys and many others too!
H/T : dogbehaviorscience.wordpress.com