My guinea pigs keep eating plastic. Any sort of plastic thats accidentally left out with them is immediately devoured, and yet they all seem to be in perfect health. Its been going on for a few years now but none of them have died from it... we're quite worried about it, we try to keep any plastic away from them but if we accidentally leave eg: a brush, a bag after cleaning them, anything made of plastic really they just eat it. Does anyone know what might be the problem? As i said they all seem in perfect health.