Dogs are good for your health
Dogs really can be man's best friend. They can transform, and in some cases save, their owner's life. As pets they bring joy and company but many dogs play an important diagnostic or assistance role.
They are being trained to diagnose cancer and to warn people of an impending hypoglycaemic attack or epileptic seizure. Dogs help people with disabilities, and are also being used to help autistic children.
Dogs have a fantastic sense of smell and can be trained to sniff out certain diseases. Cancer cells release small amounts of volatile substances which specially trained dogs can detect.
The charity Medical Detection Dogs is at the forefront of research into dogs' ability to detect cancer. In 2004, it contributed to the first ever scientific investigation into the detection of bladder cancer using dogs to screen urine samples.
The charity is currently running two major trials, one into the detection of prostate, bladder and kidney cancer using urine samples, and the second into breast cancer using breath samples.
It's hoped it will lead to the development of a simple non-invasive method of detecting and diagnosing cancer at an early stage through electronic systems known as E-noses.
Dr Claire Guest, CEO and director of operations at Medical Detection Dogs says: "For hundreds of years, dogs have guarded us, rescued us when we're lost and provided unparalleled emotional support. Is it so hard to believe that they can detect the odour of disease?"
"Dogs have an extraordinary sense of smell. They can detect parts per trillion; that's the equivalent of one drop of blood in two Olympic-sized swimming pools," she adds.
Hazel Woodget believes her chihuahua Pepe has detected cancer on three occasions. "He started acting strangely around me and on one occasion came and sat directly on top of my chest. I suddenly felt a sharp, searing pain deep inside my breast. I went to the doctor the following week," she told the charity. Hazel found out she had breast cancer, had a mastectomy and started chemotherapy.
Pepe's behaviour went back to normal, then he started acting strangely again. Tests revealed Hazel's cancer had spread to her mastectomy scar and she had more surgery. Six months later it happened again, this time with Pepe nuzzling her remaining breast. Tests revealed it also was cancerous. Hazel credits Pepe with saving her life.
Warning about diabetic attacks
Dogs can also be trained to help an owner with diabetes. These hypo alert dogs know when their owner has low blood glucose levels called hypoglycaemia. Dogs recognise signs of low blood sugar and respond in a number of ways. They may warn their owner, fetch a blood glucose testing kit or press a specially installed alarm in their owner's home.
Gemma was diagnosed with type 1 diabetes just before she was 3. When her blood sugar went low she didn't feel aware of it. She never woke up when she was having night-time hypos so her parents were testing her for hypoglycaemia 15 times during the day and night.
Help was at hand in the form of a black Labrador called Polo, a medical alert assistance dog. Polo can detect if Gemma's blood sugar is too low and alerts her parents.