Feeding Dairy Cows When Corn Prices are High

Take Home Messages • The diversion of corn away from livestock to the production of ethanol is likely to increase in the future, so corn prices at the dairy farm are likely to remain high for the foreseeable future. Corn prices are about 50% greater now compared to 8 months ago. • Alternative grain sources high in starch are too expensive or unavailable in Florida. Hominy can partially replace corn because it contains about 75% of the starch level of corn and is priced about 30% less than corn. However the cost per unit of starch still favors corn. • Although the ideal starch concentration in the diet of the lactating cow is between 24% and 26%, it may be reduced by replacing it with byproducts that contain highly digestible fiber such as corn gluten feed and soybean hulls. Due to their lower price, ration costs may be decreased by $0.20 per cow/day when they are fed at 10% of ration dry matter and starch concentration is reduced by 2.5% units (gluten feed) to 4% (soybean hulls) by partially replacing corn. • Although dried distillers grain with solubles is very low in starch, it is an excellent source of protein (30.3%), fat (13%), and digestible fiber and therefore has an energy density very similar to corn. One pound of distillers can replace about 0.6 pounds of corn and 0.4 pounds of soybean meal. If corn and soybean meal are priced at $182 and $266 per ton, then the breakeven price for DDGS is $215/ton. • Growing corn silage hybrids having higher starch contents can reduce the need of ground corn in the diet. • Glycerol, a byproduct of making diesel fuel from animal or vegetable fat, can be fed at 5 to 10% of ration DM as a corn replacement. Concentrations of methanol in glycerol-based products that exceed 0.015% prevent glycerol from being considered a safe feed by FDA. • Close attention must be paid to ensure that byproducts have consistent and high quality nutrients over time. Elevated phosphorus, fat, and damaged protein should be monitored for regularly in for most byproducts.