Ok, I am a novice at chickens so bear with me if this is a dumb question but I have noticed that 3 of my chickens look like the right side of their front, what would be their breast area, is popped out. Almost lopsided. If I touch it, it seems normal feeling but just looking at the hens you can tell there is a bump. It doesnt go down and not all of my hens have it. One is 7 months old and the other 2 are 2 years old.