AS SICK AS A DOG. - - Black pudding for you. (Spanish)

• AS SICK AS A DOG.

As a Shih Tzu owner I can't understand this idiom, but I've found on the web that the dogs are supposed to eat all they find in the street, so that's why the get sick many times.

Here in Spain we have another idiom related with that. "Que te den morcilla" (Black pudding for you).

It's nearly like "Fuck you" but not so hard. And it has an explanation too. During the blackdeath (the peste), in the streets of some Spanish cities, street dogs get the illness too. The problem was that if they bite someone they could take the illness too. So they decided to kill all of them. How? With full poisoned black puddings along the streets. And it worked.