Used to pick up the occasional trout on bread intended for chub, whilst trotting the Deepdene stretch of the River Mole in Dorking years ago. Have also had eels take bread, again trotted for chub, but during the night on the River Beult in Kent, using one of those green 'glow-in-the-dark' floats you used to have to shine your torch on to activate it, before proper night floats had been invented although in all honesty I did find worms more successful.
i have seen trout take bread thrown into the water for ducks on the mole at cobham.caughtbsome smashing little Browns on bread on the river