Invited Review: Applying fungicide on corn plants to improve the composition of whole-plant silage in diets for dairy cattle

Purpose: Published literature and data from the author's group pertaining to fungicide application on corn plant used for whole-plant corn silage (WPCS) was reviewed to summarize the effects of the aforementioned strategy for fungi disease control in the corn plant on WPCS quality and dairy cattle performance. Sources: The main source of data and information for this review was peer-reviewed literature. Synthesis: Whole-plant corn silage is the most commonly used forage in diets of dairy cattle in the United States. The interaction of fungi and corn plants reduces yields, decreasing the efficiency of food production, and the nutritive quality and value of this material when fed to ruminants. When infecting the corn plant, fungi reduce its nutritional content available by metabolizing sugar compounds within the plant cell. Applying fungicide to corn plants can protect corn plants from fungal infection, therefore limiting yield losses and increasing the nutritive quality of the plant material. There is limited information regarding feeding dairy cows WPCS from corn plants treated with foliar fungicide. However, findings from previous research highlight the negatives of making and feeding WPCS from diseased corn plants. Conclusions and Applications: Scouting corn plants for foliar disease is an important practice to determine fungicide application. Nevertheless, foliar fungicide application on corn plants used to make WPCS for dairy cattle seems to improve its nutritional composition. Mainly, factors attributed to it are increased milk components and feed efficiency, reduced fiber concentrations, and improved ruminal degradability, independently of visual identification of foliar diseases.