The early ensiling period is critical to silage quality and stability. This is when newly harvested forage begins the transition to stable silage. Driving a fast, efficient fermentation is essential to maximizing dry matter (DM) recovery and preventing spoilage, says Renato Schmidt, Ph.D., Forage Products Specialist, Lallemand Animal Nutrition.
"A fast, efficient front-end fermentation will help stabilize the silage environment and reduce yeast growth, which is the major cause of silage heating," Dr. Schmidt says.
Ensiling involves acidifying, or "pickling," the crop, and fermentation is an anaerobic process involving the conversion of sugars into organic acids, with lactic acid the main driver of a rapid pH drop. These acids are mainly produced by lactic acid bacteria (LAB), which are present naturally on the crop in variable numbers but in guaranteed quantities by using a quality inoculant.
After the silo has been filled and sealed, the forage contains entrapped oxygen. This oxygen is reduced by respiration of the plant material and by growth of microbes such as yeasts, molds, enterobacteria and LAB. During this stage, the pH will start to fall if the population of the LAB is sufficient, Dr. Schmidt notes.
Once the silage becomes anaerobic, the ensiling fermentation and conversion of forage to silage begins. For successful fermentation, the pH should be rapidly reduced until it is below 5, continuing until the pH is low enough to stabilize the silage.
"A slow initial fermentation can allow the growth of spoilage microbes," he says. "Rapid production of lactic acid is very important to maximize DM and digestible nutrient recovery. Using a quality inoculant and good application technology can help ensure the population of LAB is sufficient to drive a fast, efficient front-end fermentation through the total forage mass."
Quality, proven forage inoculants can help ensure silage hits the correct pH targets and acid profile to promote stability and maximize DM and nutrient preservation. Specific LAB are more suited to the task than others. For instance, Pediococcus pentosaceus 12455, provides an efficient, fast fermentation that is fueled by sugars generated by high activity enzymes.
"The early ensiling period is a critical time in silage production," Dr. Schmidt says. "Using a proven inoculant can help ensure the right LAB are present to reach a stable pH."