As general rule, cattle consume approximately 50 bushels of corn during normal finishing. However, you asked about from 200 to 1200 lb. If you start calves on grain this young and small, they tend to eat less corn per day but for many more days. Holsteins are commonly handled this way. Using them as an example, they will typically gain 2.8 to 3.0 lb per day, so to gain 1000 lb, they would require 333 to 357 days. They will generally convert at 5.5 or maybe better, or, in other words, the pounds of feed required per pound of gain. This means they eat approximately 15.5 to 16.5 lb of DM over this entire period. They will eat less early and more later, but this should be the average. If that diet is 80% corn, which would be typical, then 16 lb/d * 345 days * 0.80 = 4,416 lb of corn DM. If corn is 14% moisture, then that is 5,135 lb (as-is) = 4,416/0.86. Assuming 56 lb per bushel, that equates to 92 bushels.
A fair range would be 80 to 100 bushels for this type of finishing system. Again, most colored cattle (beef calves) would be fed in systems from 600 to 1300 lb for "calf-feds" or 800 to 1400 as yearlings. Finish weight can vary from 1200 to 1400 lb or even more.
