Isoimmune thrombocytopenic purpura in piglets.

A haemorrhagic diathesis due to isoimmune thrombocytopenia occurred in the fourth litter of a Landrace sow. Maternal antibodies, absorbed by piglets from the colostrum, were incompatible with platelet antigens inherited from the sire. The severity of haemorrhage varied between piglets although all were thrombocytopenic. Two deaths occurred, one at 24 h and the other at 3 weeks of age. The surviving 11 piglets were clinically and haematologically normal at 16 weeks of age.