swelling on chick shoulder

[snazzyboots]

i have a chick that hatched late yesterday. when it hatched it had a swelling on it's right shoulder. it is very soft. prob filled with fluid. the chick is eating drinking and doing well. doesn't seem to bother him. should we worry? any idea as to cause? thanks

 

[scratch'n'peck]

If it doesn't seem to bother the chick, just keep an eye on it. not sure about cause

 

[snazzyboots]

thanks