Yeah, you need more than one. Once one dog starts the others generally join in. I have 4. 3 Pyrenees mixes and 1 pit mix. 2 would probably take the food if by themselves but, the pit mix which I have nicknamed psycho would not. She won't take food or snacks from me. She is my daughter's dog and has bitten me twice when just messing around with my daughter. One time she drew blood. Had to put my foot down on her then but, she will still growl at me if I physically play with my daughter. I am good with it because I know she will tag anyone who comes near my daughter. She is the first at the door when people come up to the house and gets the others riled up.