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"Poisonous" does not mean deadly. Some manifestations of toxicity are subtle. The dose, as always, determines if a plant is safe source of nutrients or a toxic hazard.

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BRIEF: Can you give me some advice?

I have a 3 month old foal down with ergot poisoning from eating rye grass. Has been down for 30 hours; struggles to get up and is uncoordinated in all limbs. She has restricted breathing. Local vets have advised that there is no known remedy other than runnimg its course with feed supplements and water. I would appreciate any advice that you may be able to supply.


Ryegrass poisonings are not only heartbreaking, but also confusing. I guess you are in New Zealand, so you are probably talking about a perennial ryegrass? The classical staggers in NZ ryegrasses is caused by an endophyte fungus called . It produces a family of toxins that may have caused the symptoms you are observing in your foal. If so, your vets are correct, it probably will recover and there is not much you can do right now. Just keep it away from that rye grass (or dilute the ryegrass intake with a better feed) in the future. This fungi is common in perennial ryegrasses because it does not hurt the plant and it confers resistence to a variety of pests. It is also true that rye and rye grasses often have ergot on them, which also causes some neurological symptoms of its own, and also a fever. Some believe that the Acremonium can also produce the fever-inducing factor. Ergot also raises havoc with reproduction and milk production. If you are dealing with an annual ryegrass, you may be in for even more trouble. The symptoms of annual ryegrass poisoning are more severe, often fatal and result in permanent brain damage in survivors. The corynetoxins are produced by a bacteria carried by a nematode, aided by a phage (sort of a bacterial virus). Up until recently, it was thought that only frequent burning of pastures (traditional in the US) or meticulous pasture sanitation could control this awful situation, but another fungus has come to the rescue in some places: Dilophospora alopecuri kills the nematodes that harbor the bacteria that slimes the grass and kills the stock. If you would like to read more about this, see Peter Cheeke's new edition of: Natural Toxicants in Feeds, Forages, and Poisonous Plants (Chapter 10). P.S. If the foal were suffering from anencephalomalacia (unrelated to the ryegrass) caused by a frank or pteridophye-induced thiamine deficiency, then it might respond to some injected thiamin, but I would not bet on it....