Hello all. First hatch here and chick number 10 has a funky butt. Is this a herniated umbilical cord or unabsorbed yolk? Sorry for the state of the incubator. The chicks have been hatching for the last 3 days.
Welcome to BYC! That looks like post hatch gunk that can sometimes still be attached. It should dry up and fall off and the slight protrusion should also recede and go down. I would look out for other chicks pecking that area.