I usually feed speltz to my horses,but this year I must feed barley.I am feeding spring barley and running it thru a crimper.My question is how many pounds would I feed to a 1800 lb Belgian.Will the amount given be before or after crimping?

Michael, my advice is going to be not to feed barley at all. It is very high in starch and sugar which risks founder, colic, and EPSM muscle issues (which in drafts can be fatal). For extra calories you'd be better off with beet pulp (without added molasses) and added vegetable based oil. This is actually fairly economical as well, as the beet pulp should be inexpensive and you can buy soy oil (vegetable oil) in bulk at Sam's Club, Costco, or restaurant supply stores. If you have to feed barley I'd feed the absolute minimum - quite honestly I don't consider barley to be a safe feed for horses, especially drafts.