Why do Labradors easily put on weight?

Scientists have found a genetic mutation, which explains why some dogs are constantly hungry and often become overweight. Researchers at the University of Cambridge say one in four Labradors and two-thirds of Flat-coated Retrievers have the mutation, which also means they burn fewer calories. Newshour's Rebecca Kesby spoke to Dr Eleanor Raffan, researcher at the Department of Physiology, Development and Neuroscience at the University of Cambridge.

(Picture: Labrador retriever. Credit: BBC)