Toxicity of dietary scopolamine and hyoscyamine in pigs

The subchronic toxicity of synthetic scopolamine and hyoscyamine mixture (ratio 98:2 as in Datura ferox seeds) was investigated in 40 growing pigs fed diets containing 0, 1.5, 15, 75 or 150 mg of synthetic alkaloids per kg feed. Growth performances, clinical signs, and blood variables were recorded. Three and five pigs were slaughtered on day 14 and 76, respectively, for anatomico-pathological and histological observations. Growth inhibition occurred in all diets containing synthetic alkaloids; the higher the alkaloid concentration, the sooner feed consumption and growth were affected. At the end of the experiment, the control group had higher mean live weight by 5.8, 8.1, 11 and 20.7 kg than groups receiving 1.5, 15, 75 and 150 mg/kg of alkaloids, respectively. The high levels of alkaloids increased the blood concentration of total lipids, cholesterol, triglycerides, suggesting that high levels of alkaloids (75 and 150 mg/kg) increased body fat mobilization. The pigs in these groups had also increased blood concentrations of urea and uric acid. Liver, heart and spleen weights were not affected by alkaloid levels. The most important alteration appeared in the gastro-intestinal tract where the mucous membrane showed lymphocytic infiltration and a loss of epithelium. The villi were necrotic and replaced by dystrophic regeneration. It can be concluded that the intake of a synthetic alkaloid mixture even at the level of 1.5 mg/kg feed is not acceptable for long-term supplementation. © 1997 Elsevier Science B.V.