How much space do you need for that much feed, and what type of building? Can you get the seed stock at a reasonable price for that amount of feed?
From my research Barley would be best, it's $5.10 a bushel which is 48lbs (assuming buying bulk). 1 lb of seed makes 7.33 lbs of fodder, cows need 2-3% body weight daily depending if your maintaining or feeding out.
A batch of fodder is ready every 6 to 7 days. I have a 48×64 pole shed already and that would be large enough to produce all I'll need.
Hard part is maintaining 60 to 65 degrees in the shed, this allows fodder to grow but prevents most mold growth. We can easily do it in the fall, winter, spring but we wouldn't be able to in the summer without huge AC bills.