Granulation tissue that develops at the umbilical level in calves a few days after birth, following a chronic inflammatory process. This condition generally occurs when the umbilical arteries rupture outside the umbilicus and protrude from the umbilical sheath, instead of rupturing at the level of the umbilicus and retracting into the abdominal cavity (persistent umbilical cord).
Therapy: surgical excision or tight ligation at the base.
