DTN is rerunning this column from our archives because it's still relevant and useful advice. ** READER QUESTION: We raise calves off of dairy farms, and sometimes we get a bull calf with a rupture that shows up by the navel at around 8 to 10 weeks of age. Why is this happening? DR. KEN MCMILLAN'S ANSWER: These are most likely umbilical hernias. The umbilical cord carries nutrition and removes waste between the dam and the fetus. When the calf is born, that cord should wither away, and the body wall should seal. If that doesn't happen, there is a weakened area where organs can fall through, including the intestines. This can become larger over time, and if the intestines become strangulated, the calf can die. Another possibility, based on what you describe, is an infected navel (navel ill). In this case, the umbilical cord is infected and swells. This type of infection can actually lead to infection in other parts of the body, including the joints (joint ill). If this is a hernia, ...