What is that on my newly hatched chick?

[Retrosveni]

Hello
I have hatched quails again, and one of them has this thing? On the belly. At the spot where the yolk gets absorbed. Those someone know what that is? The chick seems completely fine otherwise.

 

[Nabiki]

I might be unabsorbed yolk. It also might be something wrong where the abdomen didn't close up completely. Keep an eye on it. If it's yolk, then it will go away in less than a day.

 

[Susan Skylark]

If it doesn’t absorb and close up properly in a few days it is probably the bird equivalent of an umbilical hernia, could also be a growth or mass of some sort, uncommon but possible. I’d just leave it alone and as long as ot doesn’t get bigger, break open, get pecked at, or cause trouble to the bird just let it be.