Issues of Silage
Silage is the base for your cow’s diet in the winter months and so is crucial to economic milk production and healthy cows. The importance of making good silage should be your number one priority each summer.
Management of silage involves harvesting at the right time to capture more nutrients from the crop and having the confidence that your choice of inoculant will enhance this process and allow you to produce nutritious and palatable silage every time. Achieving this means your options for balancing the diet are easier. Stability is a huge factor in achieving high intakes.
Lactic Acid
Acidosis is caused by low pH silage and this is a key factor in lowering intake potential and is often seen with more young early-cut, high nutrient grass and forage crops. Therefore controlling lactic acid levels is necessary on many farms today.
Most silage additives contain lactobacillus, which can lead to excess acidity in the forage. The Optimize silage additive formulation however does not contain Lactobacillus, and as a result produces very palatable, non-acidic silage.
Lactic acid production in Optimize treated silage is entirely derived from naturally occurring lactobacillus. All forage crops contain sufficient numbers of lactobacillus colony forming units per gramme, it is therefore not necessary to add more through a silage additive.
The figures below, courtesy of The Kingshay Farming Trust demonstrate that normal grass silage naturally contains large numbers of lactobacillus and yeast and mould spores:
Lactic Acid Bacteria (cfu/g) - 1,221,000
Yeast (cfu/g) - 41,721
Mould (cfu/g) - 193,473
cfu/g = colony forming units per gramme of grass
Source: Kingshay
With correct silage-making practice there is always sufficient naturally occurring lactobacillus to reduce the pH to 4.00 - the desired pH for high intakes. Species of Lactobacillus convert plant sugars into lactic acid.
Plant sugar is a perfect energy source for a dairy cow and it is beneficial to the stability and digestability to limit lactic acid production whilst achieving stability. Higher levels of lactic acid can lead to instability and also inhibit intakes.
Spoilage Organisms
The primary function of the Optimize bacillus is to minimize spoilage organisms such as yeast and mould and soil born pathogens such as clostridia and listeria.
Stable silage is the main objective meaning your cows want to eat more, achieving a healthy digestion which offers higher production and milk quality. In the trial the high aerobic stability achieved by Optimize meant that the silage stayed cooler for longer than with the no additive control.
The UK climate is becoming warmer and damper which encourages greater yeast and mould growth on crops whilst they are growing. Spoilage organisms created by yeast and moulds (mycotoxins) are now recognised as a common contributor to inhibited performance during the winter months.
"Aerobic stability is an important factor to consider in assessing the production capability of silage."
Unstable silage can heat up to 1m behind the silage face. When this happens the silage is already spoiled as well as reduced in ME before you feed it to your cows. If the silage is spoiling faster than you can feed it, then significant feed value is lost.
The presence of mould may also lead to lower feed intakes and lower utilisation of the silage. In addition the silage can loose volume in the pit and in the trough meaning as the winter progresses the silage volume reduces faster than it should which can cause a shortage of silage before turn-out.
Kingshay Silage Trials
In the Kingshaw Silage trials Optimize verses untreated silage affected the aerobic stability of the silage in different ways:
1)The no additive control increased in temperature significantly faster than the Optimize treated.
2) The trial proved there was plenty of naturally occurring lactobacillus on the forage to ensile and acidify the crop to the required 4.00 pH.
3)The yeast and mould stabilising properties of the Optimize bacillus used in conjunction with lactobacillus already available on the crop (see chart below) results in stable forage. This is easier to manage at feed out, is more palatable with less waste and does not reduce in volume in the pit.
"Aerobic stability is an important factor to consider in assesing the production capability of silage."
