not sure if u will like but here goes.
Attack dogs would be a kill streak.It would take 6 kills without dying to release 3 dogs.Dogs are easily killed with 1 shot of any weapon. they are very fast and will jump on you. you have 2 options to get rid of them once they are on you. 1)A teammate will shoot it off. 2)You can snap it' neck when the screen tells you to left click. 2 seconds until it eats your neck, so 1 second should be enough to left click to snap it's neck.
So what do you think?:)