It’s hard to open any recent dairy industry periodical and not see articles discussing high feed prices and low milk-to-feed ratios. Regardless of how high or low feed or milk prices are, dairy producers should always be looking for the biggest bang for their buck. If buying ground corn, either in a mix or alone, you should be aware of how finely the corn is ground.

Cracked corn or coarser ground corn has lower processing cost but is not as efficiently used by dairy cattle. Grinding corn finer increases the surface area available for digestion. By decreasing the grind size you may be able to improve the energy utilization, increasing milk production with the same amount of corn. The table below (adapted from data from Farmland Industries presented by Dr. Mike Hutjens) shows the difference in performance between cracked corn and ground corn. Cows receiving ground corn had a slightly higher DMI; they produced 6 more lbs of milk per day and tended to have a higher fat and protein percent.

So how do you know if your corn is ground fine enough? The most definitive method of determining grind size is sifting the corn through grain particle screens. Ground corn should be evaluated with the following sizes of screens, #4, #8, #16, #30 and a bottom pan. The following table lists the recommended distribution percentages of particle size for ground corn, both dry and high-moisture 25-30% (H.M).