Silage making, a technique for the conservation of wet forage in the absence of oxygen, represents the most important source of ruminant feed today. Several factors such as forage type, climate, growth stage, technique of harvesting etc. influence the ease of silage production – and, most importantly, the end quality. Producing quality silage consistently requires attention to detail across a range of techniques. These include harvesting, packing, processing of kernels in the case of maize silage, the use of silage inoculants, covering, sealing and feed out management.
Achieving rapid acidification is paramount in conserving as much of the inherent feed value of the crops we ensile. From the moment we start to harvest, deterioration and loss of nutrients occur. We aim to manage this process, called primary fermentation, to achieve our goal of maximum nutrient recovery. This process can happen naturally, being driven by epiphytic lactic acid bacteria that occur on the plant. The challenge we face is that we do not know which strains of bacteria is present, in what numbers they occur and what their efficiency is in converting sugar to lactic acid. We therefore add a microbial inoculant containing a known number of bacteria, with specific strains selected to effectively drive the fermentation process in the desired direction. There are several types of silage inoculants, but we can break them down into two main categories:
Choosing the correct inoculant for your purpose involves choosing a combination of bacteria that is adapted depending on the type of crop, the dry matter (DM) at harvest, the forage sugar content, the protein and mineral content of the forage amongst other factors. Lactic acid bacteria may also be combined with enzymes, which can help improve fibre digestibility and fuel the silage inoculant bacteria.
Yeasts and moulds