How many olfactory cells does a dog have?

Dogs have more than 200 million olfactory cells and humans have 5 million olfactory cells, 40 times more than humans. The dog’s olfactory mucosa can be as high as 30 square centimeters, plus the dog’s olfactory center is very well developed, so dogs are often used as drug detection dogs and other working dogs to use. Specially trained dogs can distinguish cocaine carried by criminals and even the smell of cancer. Owners should be careful to protect its sense of smell and not give it something irritating to sniff.