A female German Holstein twin calf showed polydactyly in both front limbs and in one of the hind limbs. In three limbs an additional medial toe was seen. No malformations of the limbs were present in the male twin partner and four maternal half sibs. The analysis of the pedigree revealed that the affected calf had common ancestors. The coefficient of inbreeding of the affected calf was 1.312%. As a monogenic or digenic inheritance was suspected in similar cases, it may be probable that the polydactyly observed here has a genetic background.