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How to take stock of forages and plan efficient winter feeding

Farmer and nutritionist looking at InTouch controller and app

Tim Kneale, Alltech InTouch feeding specialist for Southwest England, offers expert guidance for stock-taking forages and winter feed planning, with tips on how to balance and maximise forage and feed utilisation on any dairy system.


While it can feel like an extra-laborious job, there’s no getting away from the importance of feed budgeting, particularly over the autumn-to-spring housing period.

By taking a couple of hours as soon as possible in the season to work out what forage and feed stocks you have, you can plan ahead and make decisions early. This will help you avoid diet changes at critical points, as well as late (and often expensive) feed or forage purchases.

Silage production is a costly investment which is all too frequently underestimated, and margins are continually challenged by market volatility and challenging weather conditions. So, planning how to maximise forage in the clamp is a real must.

By assessing forage stocks, analysing feed-out values, and action planning to effectively balance the ration, farmers can minimise the risk of feed waste and poor panic decisions on any system.


Learn from our ruminant feeding specialists about:

  1. Assessing forage stocks
  2. Analysing feed values
  3. Action planning to balance the ration

 1. Assessing forage stocks


Higher production costs and depleted forage reserves from 2022/23 have put many farms under pressure heading into the winter.

Most farms are also having to contend with variable yields and compromised quality from the 2023 silage season. We’ve seen some maize crops down by 30%, and lower nutritional value is being observed in late-cut grass silages.

Furthering the pressure, in many cases, variable weather shortened silaging windows, which may have compromised how well the crop has been clamped. This can increase fermentation and spoilage.

As soon as possible in autumn, a few easy assessments of your clamps can help manage the pressure and enable quick but wise buying decisions in the upcoming winter feeding period.

Here are six key factors to determine how the silage in the clamp may feed out this year whilst noting what can be improved when silaging next time.

  1. Dry matter (DM): This is the most important element to keep track of to ensure that cows are eating the correct amounts of feed and forage for the level of production. DM can be established by taking samples from various points of the clamp, mixing them together for an average, and sending them off for analysis.


  1. Quantity: To ensure that you have an adequate supply for the winter plus a buffer in case of a late spring, it is crucial to know the volume available and how much can be fed per day over a set period. Establishing how many days worth of silage you have in the clamp is simple math:


[Clamp m3 (L x W x H) X silage DM] ÷ DM intake of each cow


  1. Density: The density of the forage should be over 720 kg/m2 to ensure good fermentation and reduce air ingress. Often, the top layer of forages can be seen to deteriorate once open due to poor compaction and not enough top weights. To minimise any negative impacts from aerobic spoilage, only remove the silage sheeting by 1 m at a time – ideally, the depth of the grab.


  1. Chop length: This will affect the rumen environment, as very short fibre can increase acidosis risk through lack of cudding. Long fibre might need to be chopped down in the diet feeder.


Read more in this blog on how to create the perfect TMR.


  1. Mycotoxins: Early laboratory sampling as part of the Alltech 2023 European Harvest Analysis is indicating a high risk of mycotoxins across UK silages this year.  Previous results from these analyses have found that Penicillium and type B trichothecene mycotoxins pose the greatest risk to ruminants from forages.


Read more in this blog on how to mitigate mycotoxins.


  1. Fermentation status: All the previous points will impact the fermentation potential of forages and affect the desired result. Poor fermentation will lead to increased volatile fatty acids and reduced protein and metabolisable energy, and the forages will more than likely be less palatable to the cow.

Want to put a value on your forage stocks? Alltech offers zero-fee forage assessments through its Alltech Navigate® feed waste reduction service.

Now that you have assessed your forage stocks, head to Step 2 to analyse your feed-out value!


2. Analysing feed values


As we’ve mentioned, it is at the point of harvesting and clamping silage crops that we can influence nutritional value and digestibility.

However, it is important to analyse the value of the feed in the clamp so that we can effectively balance the formulation to maximise feed conversion efficiency (FCE).

Digestibility (also known as ‘D-Value’) of forages is seen as the main indicator of quality. A higher D-Value translates to a better conversion of forage to milk. A score of 80+ would be a very digestible crop, whereas hay would score at around 60 in comparison.

Later-cut grass silages will typically have lower levels of protein and energy because the cell walls of the crop lignify and lock up the ‘goodness’. This reduces the ability of the rumen microbe to break the forage down. The D-Value is a fairly standard metric on most lab reports, but neutral detergent fibre (NDF) and fibre levels will also give an indication of the level of lignification and how the forage may feed out.

For grass crops, once the target heading date has been reached (when 50% of the crop seed heads are visible), D-Value starts to fall by up to 0.5 units/day, so any trade-off in quality for bulk will have a negative effect.

Now that you have analysed your feed-out value, head to Step 3 for action planning!


3. Action planning to balance the ration


All animals have specific requirements, and these requirements vary from group to group and farm to farm depending on the forage and output performance desired.

Here are our top three formulation tips to help extend forage stocks and balance cow rations heading into the winter:

1. Keep the focus on optimising rumen function

A greater feed conversion efficiency (FCE) translates to either the same amount of milk from less feed or more milk from the same feed. A greater feed conversion ratio (FCR) translates to either the same amount of DLWG from less feed or more DLWG from the same feed. FCE and FCR are not only relevant but massively important to every farm, whatever the market situation.

Fibre-digesting rumen microbes are designed to work in anaerobic conditions and at a stable pH range of 6.2 to 7.0. Oxygen can be considered as highly toxic to rumen microbes.

Introduction of a live yeast such as Yea-Sacc® will reduce fluctuations in pH and help keep rumen microbes steadily active. This will encourage feed digestion and rumen turnover, allowing for greater intake and improved FCE/FCR.


2. Proactively control mycotoxins before they can take hold

Nearly all forages will contain a level of mycotoxins. The question is which mycotoxins and at what level. Testing will inform your cost-effective mitigation strategy.

When mycotoxins are found to be present in any feed, farmers are advised to add a mycotoxin binder to the TMR. These work through binding the mycotoxins that have been consumed, removing them from the animal’s digestive tract before they have a chance to cause toxicity.

Mycosorb® A+ is a broad-spectrum binder which has been proven to address the multi-mycotoxin challenge, including Penicillium toxins, which, according to Alltech 37+® testing, are the most common toxins found in forages and TMRs. Mycosorb® A+ works uniquely by a process of adsorption, in which the carbohydrate components of yeast and algae cell walls. One major benefits of Mycosorb A+ is that it does not bind with other essential nutrients, including vitamins. This leaves them available to the animal.

3. Consider feeding forage extenders

These are offered from most feed suppliers and are based on cereals and cereal byproducts high in NDF. They generally have a high sugar content also.

To ensure that you get value for money, you need to consider the DM, energy and protein levels. If not, you may just be buying expensive water!

Straw and hay can also be good forage extenders and are generally more cost effective. However, there is generally a compromise with ration potential and animal performance, due to the lower nutrient density and high NDF levels. Often, there is a need to add more protein and energy to ensure good rumen function and support rumen bacterial function and growth. 

How to keep an eye on feed efficiency levels

Here are five key performance indicators to keep an eye on throughout the winter to ensure that your ration is on track:

1. Leftovers: Target <5% feed leftovers in the feed troughs, and alter your rations as needed to maintain this on a daily basis.


InTouch automatically reformulates the ration each time you increase or decrease the number of cows fed in each load.


2. Accuracy: Ensure you’re not over- or under-feeding on any of the ingredients, as this can be costly and can upset the rumen.


The InTouch controller records this data and sends it through to the InTouch hub in Ireland for continual monitoring for any major discrepancies. InTouch also prescribes a weekly email summary on loading accuracy.


3. Sorting: When they are fed high-fibre forages, hay or straw, cows have a tendency to sort through the ration and pick out the best bits. Ensuring that the ration is evenly processed, the chop length is on target, and the mix isn’t too dry, will reduce the ease of sorting and hopefully prevent it.


4. Defecating: You want to ensure that the dung is firm enough to form a thick, domed pat and that there is a slow, clap-like sound on defecation. You also want to see minimal undigested grains and fibre. This signals how well the rumen is working.


You can get a detailed picture on digestion levels from conducting dung sieve analysis, a service available from Alltech.


5. Cudding: Aim for a target of 65–70 chews/minute, a rate which suggests that cows are regurgitating feed through rumen stimulation. Additional, stiffer fibres from straw can help increase cudding by scratching the rumen wall and causing contractions. Increased cudding will also increase the natural recycling of sodium bicarb in the cow’s system, aiding in pH buffering.

Finally, some pointers to optimise stocks and quality next silage season

The weather has a big influence on harvest periods. It is ideal to mow when dry and in the morning to allow for a good wilt. Also, aim to pick up the same day when target DMs are achieved.

Leave a 7–10 cm stubble height to increase air flow around the crop, further aiding wilt and leaving energy reserves in the base of the crop.

Chop length can be a topic of serious debate, but this needs to be considered alongside the DM of the crop being harvested, in order to optimise clamp consolidation.

Target chop length for grass silage based on dry matter (DM) content:

Silage DM (%)

Ideal Chop Length (cm)

28 – 35

2.5 – 5.0

20 – 28



8.0 – 10.0

Source: AHDB

When filling the clamp, ensure that layers of no more than 15 cm are achieved, to allow for good consolidation. A target density of 720 kg/m2 will have a reduced chance of aerobic spoilage and a better fermentation potential.

For maize silage, harvest dates are different, and the decision should be based on the DM of the crop/stover and the position of the milk line on the kernels. Target DM should be 28–35% DM, with the milk line halfway down the kernel.

Read more from AHDB


Speak to an InTouch team member to access the Alltech Navigate® service.