Two of five pregnant rabbits gavaged with purified fumonisin B1 at 1.75 mg/kg/day died, one after 9 and one after 13 doses. Microscopic examination revealed focal small hemorrhages in cerebral white matter in both animals, with malacia and hemorrhage also present in the hippocampus of one. The lesions were bilateral. Both animals also had marked degeneration of renal tubule epithelium and of hepatocytes. Apoptosis was the dominant degenerative change in kidney and liver. Fumonisin is known to cause leukoencephalomalacia and hemorrhage in equines, but CNS changes associated with exposure to fumonisins apparently have not been reported in other species. This preliminary observation in rabbits is reported to alert other investigators of a potential model of the disease in equines, as well as for investigation of potential mechanisms of toxicity to the CNS. c̊ 1996 Wiley-Liss, Inc.