1) Puppies have 28 teeth while adult dogs have 42.
2) Puppies are born deaf as their ear canals are closed. However, as they grow and develop their hearing, they quickly surpass human’s hearing abilities. Dogs are able to hear higher pitched sounds. Dogs can detect a frequency range of 67 to 45,000 hertz/cycles per second, whereas humans can only detect 64 to 23,000 hertz.
3) A dog’s vision allows them to see in the dark. Their larger pupils let in more light and the center of their retina has more light sensitive cells. In addition, the tapetum is a mirror like structure towards the back of a dog’s eye that reflects light, allowing the retina the ability to register light that has entered the eye. The tapetum is also the reason why dog’s eyes glow at night.
4) A dog’s sense of smell is much more accurate than humans. In fact, it’s 1,000 to 10 million times more distinct than human’s. Depending on the breed, a dog has between 125 million to 300 million scent glands. To put this in perspective, humans only have 5 million scent glands.
5) Dog’s only have sweat glands on their paws between their paw pads. This is why they pant to cool down. This is important to remember as dogs are susceptible to overheating in warm weather and the proper precautions must be taken to prevent overheating
* Facts courtesy of VetDepot.com