Have your cow checked out by a veterinarian to determine whether it actually is laminitis or something else like foot-rot, a corm in the hoof, a leg injury, etc. The barley "hay" (is this greenfeed or straw?) will not cause acidosis. What will cause acidosis is an excess of high-energy feed like grain, as mentioned in the article above. The fibre in the greenfeed will prevent acidosis from occurring because it is in high fibre.