Millions of us wear gadgets which measure our heart rate 24 hours a day - but our pets could soon be about to join in.
Scientists at Imperial College London have invented a device which can measure animals’ heart rate through their fur.
It’s far from the first gadget invented for our furry friends - but could help owners keep track of their pets, and even help sniffer dogs do their work, the researchers believe.
It could also make animal surgery safer, the scientists said.
Study lead author Dr Firat Guder said: "Wearables are expected to play a major role in monitoring health and detecting diseases early.
"Our stretchy, flexible invention heralds a whole new type of sensor that can track the health of animals and humans alike over fur or clothing."
The study was published in Advanced Functional Materials.
The device is made from a silicone-water material which tightly moulds to the shape of the fur, clothing or body part it is placed on.
An inbuilt microphone picks up sound waves - like a stethoscope - which are transmitted to a computer.
First author Yasin Cotur said: "The sensor works like a watery stethoscope, filling any gaps between it and its subject so that no air bubbles get in and dampen the sound."
Researchers believe this technology could allow pet owners to track their animals in real time.
The technology could even help improve the work of sniffer dogs used to detect bombs and missing persons.
They are trained to sit or bark when they detect a target object like an explosive device or person stuck in rubble after an earthquake.
When dogs 'alert' to target objects, their heart and breathing rates increase because they are excited to be rewarded.
Researchers say the new sensor could help measure 'alerting' behaviour by measuring how excited the dogs are.
An inbuilt algorithm might be able to tell the strength of the dog's reaction to the smell it detects and even work out how 'sure' the dog is of finding the desired object.
The sensors have been tested on dogs and humans, but the researchers hope to adapt them for use on other pets, as well as horses and livestock.
Mr Cotur said: "The next step is to validate our system further with animals, primarily focusing on sniffer dogs and then horses and livestock later on."