Forage Conservation

Need for conservation  Feeding during drought or floods  Utilizing surplus forage  Transport of feed

Methods of Conservation  Hay  Silage  Haylage

Hay  Grasses are cut at optimum growth stage  Left in the field to dry  Machine used to turn over grass to aid drying (tedder)  Dried grass swept in rows (windrow)  Hay baler used to compress dried grass – cubes or big round bales  Can also be used to conserve rice straw

Big bale hay

Padi straw hay

Problems with making hay  Need plenty of sunshine – 3 consecutive days without rain  Easily spoilt by moulds if not quickly dried  Requires heavy investment in machinery  Large storage area is required  Can be a fire hazard

Haylage  Forage that is baled at a higher moisture content than dry hay and then stored in a sealed plastic wrap.  Because of the high moisture level and air-tight environment, the forage ferments and is preserved by acid production during fermentation.

Advantages of Haylage  Decreased curing time needed from cutting to baling makes weather less of a factor in forage harvesting.  Potential for more timely harvest of large quantities of forage.  Decreased need for mechanical handling and time curing to dry the forage reduces the loss of leaves, the most digestible part of the plant.  Potential for higher feed quality bale through leaf preservation and possible nitrate reduction.

Disadvantages of haylage  Increased harvest cost per bale vs. conventional cured hay.  Disposal of used plastic wrap.  More likely to spoil as compared to silage in traditional silos.  Risk of forage spoilage if integrity of wrap is not maintained. Birds and rodents can puncture plastic and holes must be covered.  Transportation of bales is limited due to cost of moving high-moisture bales.

How haylage is made  The forage is cut as if for haymaking, but is baled at 50 to 60% moisture rather than at 18-20% moisture.

SILAGE  Forage that is conserved by reducing pH through natural anaerobic fermentation

Advantages of silage  More palatable than hay  Not dependent on weather  Can be kept longer without deterioration  Not easily inflammable  Requires less storage area

Mechanised Silage Making

Principle of Silage conservation  Forages are conserved in an environment of low pH (4.2) and anaerobic conditions where biochemical processes and activities of decomposing aerobic bacteria and fungi are inhibited

Materials which can be ensiled  Grasses  Sorghum  Maize  Oil palm fronds  Crop byproducts (pineapple skin, cocoa pods)

Factors required for good silage  Airtight – to provide anaerobic conditions  Moisture content in forage 65-75%  Adequate soluble carbohydrates (>3%)  Compaction of materials to exclude air  Not contaminated with foreign matter e.g. soil

Silage making process  Grass is cut at optimum growth stage  Grass chopped up

Silage making process (2)  Chopped grass filled in silo:  Bunker silo  Pit silo  Tower silo  Container  Chopped grass compressed to exclude air  Silo is sealed airtight  Left for at least 21 days to complete ensilation

Tower Silo

Phases of fermentation

Baled silage

Baled Silage in N.Z. Baled silage

Baled Silage

The Silager  An invention in Institut Haiwan Kluang  Able to mechanically compress silage in a bin

Mechanical press

SILAGER II Entry for fresh fodder Forage chopped conveyor collection

Phase I  Grass is put in silo  Respiration continues  Oxygen is used up  CO 2 and heat is released  Temperature rises

Phase 2  Acetic acid is released  pH declines from 6.0 to 4.2

Phase 3  Lactic acid is released  Acetic acid declines

Phase 4  Lactic acid production continues  Temperature declines  Bacterial activity stops at pH 4.0

Characteristics of Good Silage  pH < 4.5  Lactic acid 3 -13%  Butyric acid < 0.2%  Colour: yellowish to brownish green  Odour: sweet smelling (vinegar smell)  Wetness – no seepage  Palatability – readily accepted by animals  Nutritive value – almost similar to original material

Additional steps for making good silage  Chop the material to allow easy compaction  Use additives: corn, soybean, molasses to increase soluble carbohydrates and protein (esp. if < 3% soluble carbohydrate)  Use enzymes to aid fermentation

Silage additives A. Stimulants aid in the growth of the lactic acid bacteria and the production of their acids so as to reduce silage pH at a faster rate.

Silage additives B. Inhibitors help to slow down unwanted silage degradation. For example, inhibitors may reduce mold growth or reduce the breakdown of plant proteins.

Silage additives Bacterial Inoculants are the main type of silage additive used in the U.S (about 70% of all additives). Bacterial Inoculants are the main type of silage additive used in the U.S (about 70% of all additives). They contain inactive bacteria that become active once they are put on the wet forage.

Silage additives  Sugars such as molasses, glucose, and dextrose can be added to forage to increase the lactic acid content of the silage by supplying more food (sugar) for the lactic acid bacteria to grow on.

Silage additives  Enzymes are proteins that speed up the break down of plant carbohydrates to sugars  Common sources of enzymes include, Aspergillus oryzae, Aspergillus niger, and Bacillus subtillus.