Chick Breast Split (graphic pic)

[Nicapollo]

I have a baby chick that is about 5 days old and the breast has split from its body. Almost, like it has burst out of its skin (second pic). These are broilers and now that I look at all of them I am getting paranoid. All there breast seem enlarged. This is my first time growing chickens and I have studied this site for months, Has this ever happen to anyone else? Am I over feeding or just a genetic defect? Also, it seems to me that some their breast appears to be more to one side than the other (first pic). Is this normal. Thanks for help!

 

[MaineGigi]

Are their crops really full? What are they eating? Are they outside eating from the ground?
~Cathy