gunner, if you jumped in you would've been mauled by dogs and deceased. However, if you had firearm it is possible you could have done justice. As far as being able to shoot the animals. There is Absolutely no doubt that you could do this to save child, and I have concerns for someone who wouldn't do so to save a two-yr old child. Bear in mind, weighing the option means the child dies and you talk about what-ifs sometime over a holiday dinner.
PS- here is my take on situation(I started a thread without knowledge that this one existed already):