Talking of sheep dip, I actually had to bath a cat in sheep dip stuff about twenty years ago, can't even remember why, but she was a stray who had something nastier than fleas. It was quite an experience and I don't envy anyone who has to do it. Cat went bananas, of course, and the smell in a confined bathroom space was atrocious. No wonder farmers suffer all sorts of nervous system ailments using that stuff year in year out.