A hernia is defined as the protrusion of an organ or part of an organ through the wall of the cavity in which the organ lies. I would assume the breeder is talking about an umbilical hernia, where the abdominal wall did not close all the way after the umbilical cord was removed or fell off.
Small hernias can close as the puppy grows up.
They rarely enlarge or trap other abdominal organs in the hernia opening. Larger hernias, in which part of the intestine becomes strangulated in the hernia opening by gravity or trauma, are serious and can require emergency surgery. Inc. All rights reserved.