I really dont think that picture of the giant rat is real, certainly not a rat seen in this country anyway.
I have dealt with thousands of cases of being called out where rats the size of cats were seen, when I asked where the rat was seen I would be shown the hole where it came from, about 1.5 inch diameter, ive even caught these huge monster rats in houses, I have never seen a rat any more than about 8 inches long (without the tail) When doing my pest control courses with DEFRA. the super rat often came up, they clearly do not exist according to DEFRA. The only reference to a super rat would be made about rats that had become immune to certain poisons. Generally speaking rats are really easy to control and a lot easier than mice for instance.