Toxicity of Senecio jacobaea (tansy ragwort) in rats

To investigate the toxicity of the pyrrolizidine alkaloid containing plant Senecio jacobaea (tansy ragwort), rats were fed diets containing 0 or 5% tansy ragwort and then sacrificed at 1, 2, 4, 6, and 8 weeks. Tansy ragwort produced a depression of body weight gain, food intake, and food efficiency as early as 1 week after beginning treatment. In tansy-fed rats, the relative weights of lungs, heart, spleen, adrenals, and testes were increased at 4 weeks while that of kidney was increased after 6 weeks. Leukocyte counts were markedly elevated at 2 weeks whereas the hematocrit and erythrocyte counts were decreased, respectively, at 4 and 6 weeks of treatment. At 4 weeks, total serum protein, serum albumin, and albumin:globulin ratios were decreased in the tansy-fed rats. The principal pathological changes observed in treated rats were enlarged spleen with lymphoid hyperplasia and increased hematopoietic activity, atrophied thymus, ascites, hydrothorax, and diffuse necrotizing hepatitis. The majority of the gross and histopathological changes were evident following 6 and 8 weeks of treatment.