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ARS Home » Pacific West Area » Logan, Utah » Poisonous Plant Research » Research » Publications at this Location » Publication #417336
Research Project: Developing Mitigation Strategies for Poisonous Plants in Livestock Production Systems

Location: Poisonous Plant Research

Title: Intoxication of sheep by Astragalus arequipensis in northwestern Argentina

Author
item MARIN, RAUL - National University Of Jujuy
item GARDNER, DALE - Retired ARS Employee
item Cook, Daniel
item ARMIEN, ANIBAL - California Animal Health & Food Laboratory
item FORTUNATO, RENEE - National Scientific And Technical Research Council (CONICET)
item RIET-CORREA, FRANKLIN - Federal University Of Bahia (UFBA)
item UZAL, FRANCISCO - California Animal Health & Food Laboratory

Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/27/2025
Publication Date: 3/1/2025
Citation: Marin, R.E., Gardner, D., Cook, D., Armien, A.G., Fortunato, R.H., Riet-Correa, F., Uzal, F.A. 2025. Intoxication of sheep by Astragalus arequipensis in northwestern Argentina. Journal of Veterinary Diagnostic Investigation. 37(2):375-379. https://doi.org/10.1177/10406387241311815.
DOI: https://doi.org/10.1177/10406387241311815

Interpretive Summary: Spontaneous intoxication by Astragalus arequipensis was diagnosed in a flock of 300 sheep in Jujuy province, northwestern Argentina, that grazed an area that was heavily invaded by this plant. The main clinical sign were intention tremors, ataxia, and progressive loss of condition. Autopsy of two affected animals revealed loss of body condition. The main microscopic changes were fine cytoplasmic vacuolation of cells in cerebrum, cerebellum, thyroid and adrenal glands, kidney, liver, pancreas, urinary bladder and lymph nodes, and swollen axons in cerebellum. Ultrastructurally, the cytoplasmic vacuoles consisted of dilated secondary lysosomes. Composite leaf and stem samples of A.arequipensis analyzed by high-performance liquid chromatography contained 0.05% swainsonine. The diagnosis of intoxication by A. arequipensis was made based on the clinical history and signs, gross, microscopic and ultraestructural changes, and swainsonine detection in the plant.

Technical Abstract: Spontaneous intoxication by Astragalus arequipensis was diagnosed in a flock of 300 sheep in Jujuy province, northwestern Argentina, that grazed an area that was heavily invaded by this plant. The main clinical sign were intention tremors, ataxia, and progressive loss of condition. Autopsy of two affected animals revealed loss of body condition. The main microscopic changes were fine cytoplasmic vacuolation of cells in cerebrum, cerebellum, thyroid and adrenal glands, kidney, liver, pancreas, urinary bladder and lymph nodes, and swollen axons in cerebellum. Ultrastructurally, the cytoplasmic vacuoles consisted of dilated secondary lysosomes. Composite leaf and stem samples of A.arequipensis analyzed by high-performance liquid chromatography contained 0.05% swainsonine. The diagnosis of intoxication by A. arequipensis was made based on the clinical history and signs, gross, microscopic and ultraestructural changes, and swainsonine detection in the plant.