My JR cross catches Rats and kills them BOO! Do you want to borrow her. Mind you, she isn't that good, she usually gets bitten because she catches them by the bum instead of by the neck and they turn round and bite her face.
The regular old style poison takes ages - it's warfarin and thins the blood so they bleed to death internally and seek a warm place to die. The new poisons are quicker and more humane, but I think most councils use the old style. The problem with that is that the rats crawl away into a hot spot to die usually behind hot pipes and the smell of them rotting is a smell like nothing else on this earth - totally rank and takes about 6 months to go away (if not longer).
(where did the incorrect post go BOO. I need a laugh!!)