Huff Puff the hedgehog is thought to be Britain's biggest at an average of three and a half times the size of her spiky contemporaries.
Huff Puff, right, could be Britain's largest hedgehog Photo: SWNS
The nine-month-old female weighs in at 2.04kg - the weight of a small cat - and is the size of a football.
She piled on the pounds after gorging on cat biscuits and dog food at the Furze Pig Hedgehog Rescue Centre in Ross on Wye, Herefordshire, where she was taken as an orphan.
The 15 other hedgehogs at the centre weigh around 600g each, so staff have decided to put Huff-Puff on a calorie-controlled diet.
Maureen Webb, 60, who runs the centre with husband Derek, said: "I've looked after hedgehogs for 20 years but have never seen anything like Huff-Puff.
"She just seems to keep growing. I don't feed her any more than the others but she's getting bigger and bigger.
"It's amazing because she was a tiny little thing when she came in.
"I've no idea why she keeps growing but she doesn't enjoy moving much so it could be that. I don't feed her any more than the others.
"I'm reducing her diet now and cutting breakfast out all together. I suppose it's a bit like people - some only have to look at cream teas and they put weight on."
Huff Puff was rescued after she was found cold and shivering under a garden shed in October last year.
Maureen named her new arrival because of her "stroppy" nature.
"She's a real little madam and a right prima donna. When you approach her she huffs and puffs - hence the name," she said.
"The problem is I can't release her until she's the right size because she won't survive."