Last updated at 14:29

Pictures: National fat pet slimming contestants 2013

Thirteen dogs, 5 cats and 3 rabbits are to battle it out to be crowned the most slimmed pet of 2013. This year's entries are some of the fattest pets yet.
Research from the annual PDSA Animal Wellbeing (PAW) report suggests that more than 18 million UK pets are being fed bad diets, putting them at risk of life-threatening illnesses.
Mizzy is the heaviest dog ever to take part in PDSA Pet Fit Club. Years of supersized portions mean that she can't walk very well. This gentle giant also needs to shed the pounds to improve her arthritis.Vets and nurses are coaching the owners of each pet as they embark on their Pet Fit Club journey to shed the pounds and get back in shape. Look out for the results in December 2013.
The 21 podgy pets taking part in the pet slimming contest are between them carrying around 30 stone in excess weight - the equivalent of more than 200 bags of sugar!
Larger-than-life Tia used to love playing in the local reservoir, but the lazy Lab now prefers snoozing to swimming. Her gradual weight gain over the last few years has left her weighing almost double what she should.
Roly-poly Ruby was adopted four years ago after being found as a stray. The family admit to spoiling her rotten, but she also has a nose for trouble as she once stole a chicken curry from the bin, landing her at the vets with a sore tummy! The fat pet slimming competition, which includes a six-month diet and exercise programme, has been run for nearly a decade.
Fat dog
Ulric is the largest cat ever to take part in PDSA Fit Club. Years of pinching his sister’s meals have left him so overweight he can no longer climb trees in the garden. This colossal cat weighs more than twice what he should.
Ulric the cat
Bossy Mariah used to be smaller than her sister Buttercup, but her diva-like ways meant she gobbled up more than her share of the food, and her owner now struggles to lift her.