Field and experimental studies in cattle and sheep poisoned by nitro-bearing Astragalus or their toxins.

Various species of nitro-containing Astragalus, and the toxic principle of these plants, 3-nitropropionic acid or 3-nitro-1-propanol, were fed to sheep and cattle at doses which produced chronic or acute intoxication. The signs of intoxication produced were similar to those observed in poisoning that occurs under field conditions. The signs of intoxication were emphysema and difficulty in locomotion. Primary microscopic lesions were observed in the lungs and CNS. The lungs had varying degrees of alveolar emphysema and there were varying degrees of wallerian degeneration of the spinal cord.