I guess if it's not above 45* it should be okay. Others here will know more.
My vet and I just had a similar conversation. She said you can buy it already ground/crushed if you're feeding it for fat calories (EPSM) because you're not worried about the degradation of the omegas. But if you're feeding for the anti-inflammatory effects, then grind whole flax and refrigerate.
But I know others who simply feed whole flax.
Oh wow, I didn't even think of refrigerating it to keep it good! I feed whole flax now because I thought grinding would be inconvenient, but I have a full size fridge at my barn, so that would be easy! Maybe I'll have to get a coffee grinder!
Triple Crown sells ground flax that has been stabilized. I assume they probably cryo-mill it or something. Anyhow it's not too expensive, I think $30-something for about a 25lb bag, have been feeding that to all my horses for the past month or so.
Feed it whole & you don't need to worry about the inconvenient grinding or the worry that it will go rancid. I've been feeding whole for almost a year and have noticed a significant difference in both skin conditions my mare once had and the texture and sheen in her coat.
Contrary to popular belief, it does not need to be ground...horses DO have teeth :-)
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