Clinical and analytical studies of sheep dosed with various preparations of Astragalus lusitanicus

Dosing different preparations and extracts of Astragalus lusitanicus to lambs showed the fresh plant or its dry powder were highly toxic while the ethyl acetate or methanol extract did not cause toxicosis, suggesting the toxic principle is an extremely water soluble compound. The animals alternated excitement and depression, with cardiac and respiratory disorders terminally. Alpha-mannosidase inhibition was not detected in blood of dosed lambs, but an inhibitory activity was in tissues from lambs given the fresh plant or its powder. There was increased aspartate aminotransferase and creatine kinase activity, suggesting skeletal muscle and neurological effects. Thin-layer chromatography and the alpha-mannosidase inhibition assay did not detect swainsonine in ethyl acetate, methanol or water: methanol plant extracts.