How much ground flax seed do you feed?

What is the purpose of ground flax? Forgive me for being naive, I'm fairly new to the horse world.

Maverick: I just worked Lucy up to 1/2 a cup and I think that I will stay with that amount. How long was it before you noticed a difference? Also where do you buy your flax? The cheapest I could find around here ( I haven't looked that hard yet) was a 30 pound bag for 40 dollars.

Sillybunny: I wish I was able to buy it whole and grind it, but I board and they don't provide flax grinding lol ^.^

Cowgirl4jesus: Flax seed is high in omega-3 fatty acids and enhances overall health in horses. The only natural, unsupplemented source of omega-3's in the equine diet is fresh grass.
It can help reduce inflammation, which can relieve symptoms associated with sweet itch and other skin conditions. It can also alleviate symptoms of allergies.
Because of its anti-inflammatory properties, it also helps in cases of arthritis or joint stiffness. In some cases, it helps so much that it can replace the use of commercial joint supplements or regular doses of bute.
It also boosts the immune system and can help regulate thyroid function, making it an ideal supplement for metabolic horses as well as aging horses. ^.^

Im in Canada...not sure where you are. But I buy my Flax at our local Feed dist. Called Feed-Rite (I believe it's a Canadian company)

I started to notice a difference prob around 3 months, and by the 6th month you could really see the difference esp in My 16 yr old geldings mane/tail.

My two year old gets a cup a day with his dinner. A horse nutritionist recommended that for him. He has only been on it for a month now.

I finally bought a 50 pound bag ^.^

I hope it will take about that long to see a difference, but with it being winter and all I think it will probably be longer.