By Kim Ricardo
Drought-stressed corn does not necessarily represent a complete loss of feed value. As discussed in the companion article on utilizing drought-stressed corn for forage, timely harvest and proper ensiling practices can preserve much of the crop's remaining nutritional value and provide an economical feed resource during dry growing seasons.
However, successfully harvesting drought-stressed corn is only the first step. Environmental stress can also alter plant chemistry, increasing the potential for nitrate accumulation and mycotoxin contamination while creating greater variability in nutrient composition and forage quality. These changes can influence both animal performance and health if the forage is not properly evaluated before feeding.
This article focuses on the feeding management considerations that follow harvest, including how drought affects feed quality, strategies for managing nitrate and aflatoxin risks, and the importance of forage testing when incorporating drought-stressed corn into livestock rations. Understanding these factors allows producers to safely maximize the value of drought-damaged corn while minimizing risks to animal health and productivity.
Nitrate Concerns
Drought-stressed corn may accumulate nitrates, particularly in the lower portion of the stalk. The risk is often greatest when drought conditions are followed by rainfall or when excess nitrogen remains available in the soil. Management practices to reduce nitrate risk include:
- Raising the cutter bar and leaving approximately twelve inches of stalk in the field
- Testing forage when drought stress or high nitrogen fertility conditions are present
- Avoid feeding high-nitrate forage without proper management
- Avoiding non-protein nitrogen supplementation when nitrate concerns exist
Because the fermentation process can reduce nitrate concentrations, testing silage after ensiling provides the most accurate assessment of feeding risk.
Source : sdstate.edu