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    Understanding dry matter losses

    Dry matter (DM) loss is often called silage ‘shrink’. When silage shrinks, there is less available silage.

    In addition, these dry matter losses are made up of the more valuable nutrients such as sugars, starches and soluble proteins. This leaves a higher concentration of lower-value nutrients, like fibre and ash.

    Risks of dry matter loss

    Dry matter losses occur by two primary means:

    • Losses during the initial fermentation (ensiling)
    • Aerobic spoilage losses

    With spoilage losses, the key is to prevent or delay the growth of spoilage bacteria, yeasts, and subsequently moulds, that grow when oxygen gets into the silage at feed out. This can result in silage heating. Dry matter losses can occur once the silage face is exposed to air during feed out. 

    Making silage is storing energy

    Phase 1
    Aerobic phase

    • Aerobic respiration eliminates oxygen
    • Normally takes just a few hours

    Phase 2

    • Conversion of carbohydrates and sugars to organic acids
    • Rapid drop in pH
    • Drop in temperature

    Phase 3

    • Clamp becomes stable at pH 4 – 4.5
    • Theoretically endless

    Phase 4

    • Clamp opened to air for feeding
    • Potential for reheating and energy loss

    Potential problems

    • Reheating and energy loss
    • Low aerobic stability due to insufficient lactic and acetic acid
    • High amount of non fermented sugars
    • Material not used fast enough, face of clamp open for too long

    The effect of mould count on DM losses

    Relationship between mould count and DM losses

    Energy given off as heat is energy lost

    Reheating by 10ºC leads to a reduction in methane of around 4% per day.

    Treated and untreated silage

    Financial benefits of silage additives

    ✓   The average UK maize crop costs around £450 / acre to grow
          At 18t / acre = £40 / tonne FW (32% DM)

       Poor clamp management can lead to considerable losses
    Untreated maize can average 15% loss
          Loss of 45 tonnes of DM for every 1000 tonnes of FW ensiled
          Costing £3,736 in total or 3.74/tonne FW

       Silasil Energy will help reduce losses in the clamp 
          If DM losses are cut to 5% saves 30 tonnes DM
          Worth £2,490 in total or £2.49/ tonne FW


    For more information

    For more details about reducing your dry matter loses contact our specialists here or visit our product pages: