Relationship of Relative Total Alkaloid Concentration and Toxicity of Duncecap Larkspur during Growth

Abstract

The toxicity of duncecap larkspur (Delphinium occidentale Wat.) was measured by a mouse bioassay and correlated relative to total alkaloid concentration for 5 samples during one season of plant growth. The concentration coefficient was -0.920 (standard error of estimate = 0.090) when this relationship was described by an exponential equation of the form Y = ab^x, where Y equals the total alkaloid concentration and X equals the LD50 for mice. The values a and b were estimated to be 5.410 and 0.978, respectively. It is predicted that over the entire growing season, toxicity of larkspur measured by mouse bioassay will be better correlated with toxicity to cattle than will be the correlation of relative total alkaloid content and toxicity to cattle.