Livers of laying hens of Hy-Line No 934E on low erucic acid rapeseed meals and rapeseed oil were studied. Gross lesions in the livers of hens on experimental diets were moderate to severe fatty degeneration, focal necrosis and moderate to severe haemorrhage. Histological examination revealed oedematous foci and lysis of hepatocytes along with large amounts of lipid droplets in the necrotic lesions. Necrotic lesions were not always associated with large haemorrhages. Connective tissue infiltration of older degenerative and haemorrhagic lesions was not extensive. Abdominal haemorrhage from livers occurred when extensive necrosis in the form of hepatocyte lysis and some vascular changes were present, suggesting hepatocytic degeneration caused by toxic products or their metabolites present in rapeseed by-products.