Used my gun for the first time in defense against a dog. Before going ahead I should say I fired a warning shot and ended the fight. Now, to what happened. I own a Boxer named Bruno, every morning we'll go out for a walk around the farm checking on the cows and for him to use the bathroom. This morning I had left over chicken to give him, we go out and I dumped the food in the yard. While I was doing that our neighbor's dog named Sugar came over. I believe he's a lab very fat. Sugar gobbles the chicken before I could stop him. When I told him to stop and I took a step, he backs away but then tries to go around me before I could turn around to keep a eye on him, Bruno growled and that's all it took. Both started biting and trying to topple each other. I was too slow to move and Sugar lunged at me and got my knee. I knew not to pull but to shove, so I kneed him hard in his open mouth. Didn't break the skin but left two nasty bumps. I grabbed a shovel that was laying there and smacked Sugar, he backed off giving Bruno the upper hand. Had to smack Bruno since he was ripping the skin off of Sugar, that gave Sugar time to get back on top. At this point I reached for my firearm and I didn't want to shot either dog since neither was after me, so I aimed at the back of the farm and fired one round. Bruno backed behind me looking and Sugar ran back to his house. I ended up with a two bumps on the knee and Bruno after cleaning all the blood off just had a small gash above his right eye. I'm debating to go to the neighbor and let them know what happened or let it go since me or my dog has series injuries. I did take pictures.