Are you a dog person? Maybe you have one at home and enjoy taking it for walks and curling up with it on the sofa. Personally, I'm not that kind of person – for me they're aggressive, smelly animals that need constant care and lack the independent nature and intelligence that cats have. But given the life-saving skills that some dogs possess, maybe I should give them a second chance.

To some a perfect pooch might be one that looks cute, is loyal and sits when it's told but that's about it – it's just a pet. But to really be man's best friend, they need to do something useful. Some breeds that have amazing sense of smell are put to good use as sniffer dogs or detection dogs, and are trained to use their senses to detect substances such as explosives and illegal drugs.

You'll often see them at airports or working with police out on the streets.
Other types of working dogs include guide dogs, hearing dogs and mobility dogs all providing a life-saving service to their owners. Some dogs can alert emergency services when their owner has a seizure. And there are clever canines that have been trained to provide affection and comfort to people in hospitals, retirement homes or schools and to people with autism.

New uses for dogs are being discovered all the time. Dr Claire Guest is CEO of Medical Detection Dogs, she says "although the dog has a fluffy coat and a waggy tail, he is in fact a highly sophisticated bio-sensor. You know, evolution has given him this highly sensitive nose, going down to parts per trillion."

It's this incredible ability that has led to the UK's National Health Service assessing whether dogs can be used to detect early stage prostate cancer - vital for improving survival rates.

The dogs - usually from the gundog breed, such as labradors and springer spaniels - are taught to detect a sample of urine from a patient with prostate cancer.

It's also managed to train dogs to detect changes in blood glucose levels in people suffering from type 1 diabetes. One patient, who has one of these medical alert assistance dogs, told the BBC that "in the three and a half years we've been together, he has alerted and potentially saved my life 3,500 times. And he does it all for a dog biscuit."

To save a life for a dog biscuit seems a small price to pay so maybe I should have more admiration and respect for our four-legged friends – maybe cats aren't so smart!