The price of fertilizer nitrogen has skyrocketed over the past couple of years, making beef producers question whether higher forage production from fertilization is worth the cost. In many cases, it probably is, but in others, there are alternatives. New research from the University of Nebraska demonstrates that supplementation, particularly with dried distillers’ grains with solubles, can more than make up for lower production on non-fertilized pastures. Cost-effectiveness, however, depends on relative prices of nitrogen and DDGS, and on the owner’s marketing plans.

Over three years, the Nebraska researchers collected data on seven-weight British-crossbred steers, either stocked at four animal unit months per acre on smooth bromegrass pastures fertilized with 80 pounds of nitrogen per acre, stocked at 2.8 AUM per acre on non-fertilized smooth bromegrass pastures, or grazed on non-fertilized smooth bromegrass pastures at the same stocking rate as those on fertilized pasture but supplemented daily with 5 pounds dry matter of DDGS.

In this trial, the supplemented steers on non-fertilized pastures gained 53 percent more per acre than those on fertilized pastures and 105 percent more per acre than the control group, with the higher gains per acre attributed to higher stocking rates and animal performance.

The researchers note that cost of gain tended to be lower for cattle on fertilized pastures. Profitability through the grazing period was lowest for cattle on non-fertilized pastures, intermediate for cattle supplemented with DDGS and highest for cattle on fertilized pastures. Profitability for supplemented steers sold at the end of the grazing period was reduced due to the price slide on heavier cattle. But because they maintained a weight advantage through finishing, the supplemented steers had greater profitability overall. So to maximize profits from DDGS supplementation during grazing, producers might need to retain ownership through finishing.