Thehorse.com - Full Article
By Kristen M. Janicki, MS, PAS
Jun 25, 2015
Some parts of the country are experiencing drier than normal conditions and, thus, some horses living on pasture might soon have limited forage choices. Owners must take care to ensure pastures do not contain certain plant and weed species capable of producing toxins during stress conditions such as drought.
Horses aren't as susceptible to nitrate toxicity or prussic acid poisoning from plants as are ruminant species, such as cattle and sheep. A rumen's microorganisms facilitate toxin release from the plants into the animal's digestive tract. Horses, however, are monogastric (one- stomached) animals and are more capable of breaking down prussic acid in the stomach, and convert very little nitrate to nitrite (wherein lies the problem in cows) in the large intestine.
Nitrate and prussic acid toxicity in horses are rare, but when they do occur, they typically have serious consequences...
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