With increasing costs involved in silage making this year, coupled with higher feed prices, having high quality silage is a valuable asset on farm. However, do we really understand the science behind turning high quality grass into high quality silage? 

Fermentation

The aim of preservation is to retain silage quality as close as possible to the grass being harvested and avoiding unnecessary ensiling losses. Silage fermentation is the key process in the preservation of silage, which ultimately turns fresh harvested grass into grass silage. The success of this process hinges around several factors, such as decisions made when cutting, harvesting, ensiling, whether an additive is used and/or how the grass was managed before cutting.

During the process of fermentation sugar is converted into acid by bacteria (ideally lactic acid as this encourages a rapid pH drop, thus pickling the silage and avoiding nutrient/energy losses). The main issue on farm is that the process of fermentation in many clamps can be quite poor – resulting in much more of the silage dry matter and nutrient content being lost.

Where poorer fermentation occurs, bad bacteria can persist and result in the conversion of lactic acid (which we need) into butyric acid – resulting in unpalatable silage and up to a 17% loss of the original sugar content in the silage.

GrasZyme Sugarboost Silage Additive

Our high qulaity silage additive, GrasZyme Sugarboost works efficiently at dropping pH with the increased production of lactic acid, assisting a faster more efficient overall fermentation process. This rapid fermentation results in reduced energy loss and protein breakdown.

Research conducted on treated and untreated silage using our GrasZyme SugarBoost has highlighted that the desired target pH level for correct preservation of silage was reached (pH level of 4) within 48 hours, relative to untreated silage reaching this pH target after 21 days. This faster fermentation process resulted in higher nutrient retention and less energy losses within the silage clamp.

Advanced technologies in GrasZyme SugarBoost include the presence of a fructan based bacteria that can produce a fructanase enzyme if sugar levels are low. This releases additional sugars from fructans (the natural sugars found in grasses), which are unavailable in conventional silage additives. The addition of this technology has resulted in treated silage having double the available sugar for fermentation to occur.

Change in pH over time in silage treated with and without GrasZyme Sugarboost

Grass Protein

Grass protein is made up of long chains of bound amino acids which is called true protein. During the fermentation process the chains of amino acids are broken down reducing its benefits, so it no longer acts as a true protein. Furthermore, the amino acids can then be broken down to ammonia, which reduces intake and increases the pH. The role of GrasZyme SugarBoost is to speed up the fermentation process to ensure 20% less true protein is broken down, making it more available to the animal.

Need help or advice?

For a tailored plan on improving forage quality on your farm, contact your local Sales Advisor.

In the current climate of rising farm input costs, the focus must be turned towards increasing efficiencies inside the farm gate – which includes improving the quality of our core home-grown feed, grass silage. Silage quality and profitability of the farming enterprise have long been assessed side by side, with the current climate emphasising this even more for the upcoming silage making season.

Below we outline our 4 key concepts for best practise silage making this season:

1. Cutting date

At one point, every farm will have 80% DMD (dry matter digestibility) grass available to them in the field, however, the decision is often made too late regarding the cutting date,
resulting in poor quality silage. Cutting grass younger improves digestibility and protein content, resulting in a reduced requirement for high-cost supplementation.

When discussing earlier cutting dates, silage quantity is often raised as an issue. However, it’s important to remember cutting earlier allows for quicker and earlier regrowth’s, leading to increased annual yield/ha. In some circumstances (e.g., silage only land blocks), earlier cutting will also facilitate a third cut in late August, further boosting total annual silage production.

Once seed heads appear, DMD will be around 70% at most, and will drop by 1% DMD every 2-3 days thereafter. The advice to improve average quality is to cut from mid-May. Some flexibility in harvest date (4-5 days) is usually necessary to ensure favourable cutting conditions.

2. Adapting to changes in weather

Weather is the main variable on Irish farms when it comes to silage making. Unexpected changes in weather can and will delay harvesting, however when the window of opportunity arises, seize the ‘first-cut option’. Unfortunately, last year, where the decision was made to wait – the weather broke, and many farms were forced to delay harvesting for two weeks.

Optimum mowing time is late afternoon/evening when sugars are highest (following several hours of sunshine). Sugar is the fuel for fast and efficient fermentation.

3. Effective wilting

Once cut, grass should be tethered out immediately and allowed, in ideal conditions, no more than 24 hours in the field to achieve an effective wilt. We are aiming for a dry matter content of approximately 25%. Where wilting continues for long periods, grass quality is starting to deteriorate, and significant energy losses are seen.

Over the last number of years, we have become over-reliant on long periods of wilting, and in many cases over-wilting, leading to dry silage and unstable pit-faces. Dry silage is prone to secondary fermentation, heating and energy losses.

4. Using a silage additive

With the value that is now placed on home-grown forage, achieving a good fermentation to preserve it is more critical than ever. The use of an additive has long been proven to improve fermentation, leading to less waste. Aside from less dry matter losses, the main aim of using an additive is to retain as much nutritional value as possible from the field to the pit. Silage treated with an additive has been proven to achieve a better feed-out, with increased dry matter intakes, added energy content and increased digestibility, resulting in improved animal performance.

Our GrasZyme SugarBoost is proven to:

• Increase ADG by 110 g/head/day in beef situations
• Increase milk production from forage by 1 litre/cow/day
• Increase DM intakes by 0.4 kg/head/day
• Increase milk protein percentages by 0.09%
• Reduce fermentation losses by 6.1% (equates to 30t in
a 500t pit)

Need help or advice?

For a tailored plan on improving forage quality on your farm, contact your local Sales Advisor.