Editing Locoweed (section)

{{Short description|Plant that produces swainsonine}}
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'''Locoweed''' (also '''crazyweed''' and '''loco''') is a [[common name]] in [[North America]] for any plant that produces [[swainsonine]], an [[alkaloid]] harmful to [[livestock]]. Worldwide, swainsonine is produced by a small number of [[species]], most of them in three [[Genus|genera]] of the [[Angiosperm|flowering plant]] family [[Fabaceae]]: ''[[Oxytropis]]'' and ''[[Astragalus (plant)|Astragalus]]'' in [[North America]],<ref name="RalphsJames1999"/> and ''[[Swainsona]]'' in [[Australia]]. The term locoweed usually refers only to the North American species of ''Oxytropis'' and ''Astragalus'', but this article includes the other species as well. Some references may incorrectly list ''[[Datura]]'' as locoweed.<ref>{{Cite web|url=https://www.flickr.com/photos/alanenglish/417160351/|title = Sacred Datura (Locoweed) on North Kaibab Trail Grand Canyon - don't even think about smokin' this s**t uff|date = October 19, 2006}}</ref>

Locoweed is relatively [[palatable]] to livestock, and some individual animals will seek it out. Livestock poisoned by chronic ingestion of large amounts of swainsonine develop a medical condition known as ''locoism'' (swainsonine disease, swainsonine toxicosis in North America) and ''pea struck'' in Australia.<ref name="pmid2110378">{{cite journal |vauthors=Pritchard DH, Huxtable CR, Dorling PR | title = Swainsonine toxicosis suppresses appetite and retards growth in weanling rats | journal = Research in Veterinary Science | volume = 48 | issue = 2 | pages = 228–30 |date=March 1990 | pmid = 2110378 | doi = 10.1016/S0034-5288(18)30995-0}}</ref> Locoism is reported most often in cattle, sheep, and horses, but has also been reported in [[elk]] and [[deer]]. It is the most widespread poisonous plant problem in the western [[United States]].<ref name="RalphsJames1999"/><ref>{{Cite web|url=http://www.ars.usda.gov/is/pr/2010/100621.htm|title=ARS and New Mexico Scientists Take a Long Look at Livestock and Locoweed : USDA ARS}}</ref>

Most of the 2,000 species of ''Astragalus'', including many that are commonly known as locoweeds, do not produce swainsonine. Some species, including a few that produce swainsonine, accumulate [[selenium]]. This has led to confusion between swainsonine poisoning and selenium poisoning due to this genus.<ref>{{Cite web |date=2016-08-28 |title=Ranchers despise locoweed |url=https://www.colorado.edu/asmagazine/2016/08/28/ranchers-despise-locoweed |access-date=2024-05-13 |website=Colorado Arts and Sciences Magazine |language=en}}</ref>