They tend not to roam the streets.
Last time I went, I went out and bought dog and cat biscuits and was feeding them all. None of my missus's family were pleased at all about it and I was getting comments from people along the lines of 'Here we feed people, not animals.'
Thing is, people get dogs and cats as pets over there and then realise they can no longer afford to feed them, so they just kick them out on the streets and then they breed.
Anyway, the authorities there just put a load of poison down and killed the lot, including some people's pets by mistake, who just happened to be out on the street at the time.
Will make it nice for all the World Cup tourists though.