As harsh as it may sound, you'd be better turning your back and leave em to their own devices....
The fact of the matter is that some folks treat dogs much different than others and dont give a feck about it.
See, some dogs just end up with a piss poor standard of living, without any direct cruelty inflicted.
We have a pair of fat, greasy, trampy feckers down my lane, they run a horse sanctury but keep two dogs at home in total squalor, their house is almost surrounded by trees and open countryside, yet the poor mutts have never set foot out their yard, paddling round in shite a