ANN 111: Principles of Animal Nutrition and Feed Technology (2+1)

PREPARATION OF LABORATORY SILAGE

• Silage is the material produced by the controlled fermentation of a crop of high moisture content. Ensilage is the name given to the process and the container, used is called the silo.
• Laboratory scale silage can be prepared using desiccator or plastic bags as silo.

Procedure

• Strong high-density plastic bags with a capacity to hold 2 to 5 kg chopped green fodder and with no obvious holes in the seams are required. Glass desiccators or plastic containers of the same capacity may also be used.
• Fodder to be ensiled is harvested and brought to the chopping floor. The fodder is either hand chopped with a large knife against a wooden chopping block, or chopped through a chaff cutter with a rotating blade to a size of 1” length.
• Wilting of the fodder is carried out to reduce moisture percentage in order to reduce effluent loss. After wilting the forage should have a dry matter of 35 to 40 %.
• The chopped green fodder is carefully packed in the bag or desiccators. Carefully pack the material without making any damage to the bag or container.
• If necessary before packing additives can be added and mixed with the chopped green fodder. Example 1% molasses and 0.5 % salt can be added; 0.5 % urea may also be added in case of cereal fodders, grasses, sugarcane tops.
• After filling, the bag is gently but firmly squeezed by hand to expel air, and while compressed, the neck of the bag is to be twisted, turned over and tied with twine. In case of desiccators after filling to the brim, the contents are compressed and covered using a glass lid. Care is to be taken to prevent the formation of air pockets between the contents and the lid.
• The bag of silage is then inverted into a second empty bag, which is also closed and tied.
• The bag of silage is then inverted into a third empty bag and sealed. Each bag of silage is therefore triple wrapped, and seams that might be expected to leak air are doubly protected.
• For desiccators silage the gap between the lid and desiccator jar is sealed using molten wax.
• The bag or the desiccator is appropriately labelled giving details of fodder used, date of packing and due date for opening.
• The bags or desiccators are carefully stacked in a room protected against rats, mice and other pests.
• After a minimum period of one month the silo can be opened and silage subjected to analysis.