Morphology and pathology of the equine umbilical cord.

A brief description is given of the morphology of the umbilical cord and some variations encountered. In 95% of normal Thoroughbred foals the cord measures less than 84 cm. Factors which govern cord length are not known. Seven pathological conditions involving the umbilical cord are described. Increased length is the most common abnormality and predisposes to three potentially lethal conditions, strangulation of the cord around the fetus, excessive torsion, and allantochorionic necrosis at the cervical pole.