RESUMO
In a dairy farm in Lower Saxony, a male black and white German Holstein calf showed two partially fused heads, scoliosis of the thoracal vertebral column and a high-graded dyspnoea. The animal was sired by a bull used in artificial insemination. Further affected calves were not known at this farm. The radiographic examination of the animal verified the diagnosis of a dicephalus. The pathological-anatomical examination revealed a complex malformation of the heart similar to the human Eisenmenger-complex. Several environmental causes like intoxication, rectal palpation for gestation diagnosis, infections by bovine virus diarrhoea or infectious bovine rhinotracheitis viruses could be ruled out by anamnesis and virological examinations. Thus, we supposed a hereditary background for this defect.