Abstract
The concentrations of total alkaloids and individual major alkaloids including the teratogen anagyrine were measured in various plant parts of teratogenic lupins as the plants matured. All alkaloids including anagyrine were high in concentration in above‐ground parts early in growth and decreased as plants matured, except for an increase in mature, intact seeds. Seeds were highest, followed by early growth leaves and stems. Roots were lowest with mature leaves and stems only slightly higher. Pregnant cows have the greatest risk of giving birth to calves with crooked calf disease when the concentration of the teratogen anagyrine is highest and the cows are in the susceptible 40–75 day gestation period when ingesting the plant.