Puppies have 24 teeth and adult dogs have 42.

Puppies are born blind, deaf and without teeth.

Dogs see in colour but see best when the light is low.

Different smells in the a dog’s urine can tell other dogs whether the dog leaving the message is female or male, old or young, sick or healthy, happy or angry.

Dogs are about as smart as a two- or three-year-old child. This means they can understand about 150-200 words, including signals and hand movements with the same meaning as words 

Dogs like sweets a lot more than cats do. While cats have around only 473 taste buds, dogs have about 1,700 taste buds. Humans have approximately 9,000 

Dogs sweat through pads in their feet

Dogs (and cats) can carry the young of more than one stud (or tom) at the same time. 

A frightened dog will put its tail between his legs because it cuts off the sent glands in its anal region which a very vulnerable part of the anatomy. Since the anal glands carry personal scents that identify the individual dogs, the tail between the legs action is the dog’s equivalent of insecure humans hiding their faces.