You should not have a dog if you can't train them properly without threatening physical pain... Give your dogs to someone who can take care of them properly scumbag... I have had Bull mastiffs all my life and never once had to lay a finger on them or use shock collars, Time patience and compassion is the only way to truly train a well behaved gentle animal, I hope you know your dogs will grow to resent you one day... I have seen it happen with other owners who mistreat their animals and the terrible thing is that the poor animal gets the blame every single time... You should be ashamed, Learn to train your animals properly or don't have any what so ever! They are not their just because you "want one" they are part of the family and treating them any other way is just cruel, You wouldn't do this to your children so don't do it to your dogs.