Certified Crop Advisor Practice Exam

Decreasing the amount of phosphorus in animal feed has what effect on phosphorus applied to the environment?

1. Increases

2. No effect

3. Remains the same

4. Reduces

The correct answer is: Reduces

Decreasing the amount of phosphorus in animal feed directly leads to a reduction in the amount of phosphorus excreted in manure. Livestock often consume more phosphorus than their bodies require, and the excess is then released into the environment through manure. When feed phosphorus levels are lowered, the phosphorus content of the manure subsequently decreases. This means that less phosphorus is available to be applied to the soil or to runoff into water systems, thus mitigating potential environmental issues such as eutrophication, which can arise from high phosphorus concentrations in water bodies. By reducing the phosphorus levels in animal feed, not only does it enhance the efficiency of feed utilization, but it also promotes better environmental management practices by decreasing the nutrient load that could contribute to pollution. This understanding aligns with sustainable agriculture practices which emphasize the importance of minimizing nutrient losses to protect ecological health.