As a relative of the wild cherry tree, the peach tree poisons horses in the same manner.
This tree is a low, broad growing tree, usually reaching a height somewhere between 15 and 25 feet tall.
This tree grows throughout the eastern United States, and can also be found in the south-western states.
The leaves are the toxic component of the peach tree, because they can produce cyanide when they are wilted or damaged.
The ripened fruit on peach trees can also cause a problem for horses, though they are not toxic. If a tree is within reach of the pasture, horses can gorge themselves on the ripe fruit, leading to episodes of equine colic.
These trees are toxic because they produce cyanide, which is lethal to horses.
Cyanide is created when two different components in the plant leaves come together. In the undamaged leaf, the two components never meet. However, when the plant is destroyed in some manner (knocked off the tree, wilted, your horse eating it) the two components can reach each other and cyanide is produced by chemical reaction.
Cyanide is lethal because it reacts with iron in your horse's body to stop cellular respiration. Cyanide also prevents oxygen from being transported via the blood stream, so the cause of death is suffocation due to lack of oxygen.
Consumption of peach leaves can result in death within minutes of when your horse eats them, if enough are eaten. Other symptoms include:
Unfortunately, the most common scenario is that the horse is found dead in the pasture after consuming these plants because the poisoning progresses so quickly.
Very rarely will other symptoms be observed, unless the horse is found immediately after consuming the leaves.
Cyanide poisoning is curable, however, it is usually impossible to get a vet to the horse quickly enough to save him. This is because the effects happen so quickly.
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