Join Date: Sep 2011
Location: In Sunny, HOT and HUMID S.C.
Some will eat them, not all. Generally they don't taste good so most horses don't, but like people they can develope a taste for things that are normally unpleasant.
They are toxic to all horses, just as peach leaves, black walnut, Johnson grass, etc... Acorns are also not good for most lifestock (sheep included). I'm sure your local vet can give you a good rundown on all the things that should avoid acorns and oaks.
Different things are toxic for different reasons and with different levels ot toxicity. Just as humans can consume more arsenic than cyanide before it kills us.
With regards to horses and the oak it's not just the acrons, but pretty much anything on the oak (acorns, leaves, buds, etc....) consuming them can end up resulting in Kidney failure. Of course they are likely to have digestionial problems including, but not limited to, colic before the kidneys reach a critical state.
They're always going to be bigger and stronger so you better always be smarter. (One of my grandfather's many pearls of wisdom)