Congenital and hereditary tumours in domestic animals. 2. Pigs. A review

The literature on congenital and hereditary tumours in pigs was reviewed. One hitherto unreported own case was added. Sporadic cases of congenital tumours included several types found in newborn piglets. Embryonic tumours (nephroblastoma, rhabdomyosarcoma) occurred either in newborn or in juvenile animals. Cardiac rhabdomyomas were provisionally classified as hamartomas. The hereditary tumours, melanomas and lymphomas, were reproducible by experimental matings. These tumours are particularly interesting as models to elucidate genetic and immunologic mechanisms of tumour diseases. Striking is the high degree of regression in porcine melanomas and the associated melanosis.