They need to respect you as higher in the pecking order, there are strategies for this while on the roost grab said chicken and carry it around letting them know your the boss if they try pecking during this grab the beak firmly. When they learn you are the boss then you can control them when the dogs are out.
Also chasing them until they run like hell is a good way to let them know your the boss. If you back down then they think they are above you in the pecking order. As far as ripping things out of the dogs mouth , do they have access to food all the time, maybe they are hungry.
I have a 5yr old poodle and she helps me herd , the minute one of them turns around to spur her I am there to back her up. They know she is not to be messed with.