There is much more to a clamp than meets the eye

In this article, Mark Crawford, from Farmcare Products, explains what a clamp inspection can tell you and how to take this information into next season.

The most difficult thing about silage is that it is very difficult to tell how much you have gained or lost, and what it can mean to the cost per litre.

Making good quality silage is a long term investment. Therefore this type of information is essential for confident long term decisions and investments to be made (reseeding, trailing shoe application of slurry, good quality plastic, inoculant use, etc.). So you should try to assess the losses in terms of quality and quantity of the silage in the clamp. As an example we will look at a clamp containing 1000 tonnes freshweight with a DM value of 30%.

In terms of quality losses a 0.5MJ drop in ME due to poor fermentation would result in a loss of 28,300 litres of milk production. To replace this with concentrates would require an additional 12.7T of purchased feed. At £220/T this would result in additional costs of £2,800.

In terms of quantity losses, poor fermentation also produces DM losses. So a 1% loss would represent 3T of silage. Trials with high quality inoculants showed that a 5% loss could be avoided, meaning a saving of 15T of DM. This would require 13T of purchased feed to replace it, thereby at a cost of £2,850.

With these figures in mind, it is useful to continually assess you silage quality both through forage analysis and clamp inspections. From this you can look back at what may have went wrong and therefore plan to mitigate these factors for next season.

Poor fermentation

Although not very obvious to see, a poor fermentation results in a lot of wasted energy and significant DM losses. The first thing to look for is the pH. Too high and it has not fermented to the right level. This will almost certainly result in wasted protein, low levels of energy and unpalatable silage. If it is too low it means there has been too much activity from “wild” lactobacilli bacteria. This results from a slow fermentation where this type of bacteria can establish and then take over driving down the pH too far. The second thing to do is give the silage a good smell. Cows are experts at this but there is no reason you cannot train your own nose to pick out certain scents.

The table above explains what to look out for.

Causes: A poor fermentation means the conditions where not conducive for the appropriate bacteria to populate and manage the pH drop. Therefore there can be quite a few factors to manage. These include air ingress, sugar levels, DM content, fertiliser and slurry application, inoculant use.

Best Practice: Good plastic, proper consolidation of the clamp and sealing, good slurry application ensuring a quick and efficient absorption into the ground (avoiding lumps and grass tainting), ensure fertiliser has been used up through grass testing, cut grass after 11am to maximise sugar levels, aim to achieve optimum DM (28-30%), use a quality inoculant.

Aerobic Spoilage

Probably the most obvious signs of poor quality silage when you open the clamp will be spoilage due to aerobic activity. Essentially air has managed to get into the clamp (or retained in it) thereby preventing an efficient fermentation, and the propagation of moulds and yeasts.

Visually signs will include white mould and dark patches of silage. Initially these will be located on the surface and the shoulders, however as the clamp is used they may also appear on the clamp face. There will also be signs of heating which can range from the face heating on immediate contact to the air to it heating at feeding in the trough. Either way, mould and heating means a significant loss of quality and dry matter.

The table right lists common examples of aerobic spoilage, causes and avoidance strategies.

Best Practice: So in summary minimise the risk of moulds and yeasts being brought in with the grass (slurry, ground conditions and harvesting speeds, cutting and tedding heights). With high DM silages, ensure adequate rolling in thin layers and target shoulders. Ensure careful handling of bales. Use good quality silage products (plastics, inoculants and weights). And finally good clamp face management (clean cuts, get across face quickly).

Case Study – Sil-All 4x4+ definitely a worthwhile investment

William and Edwin Wylie milk 110 British Friesians just outside Dunloy, and have been making their own silage for over 40 years.

“Harvesting with our own forage wagon suits us as the grass is not too far away and we have good access to help when we need it.” explains William. “This also allows us to have more control over how and when things are done”.

Having never used an additive before and always relying on good weather management, William was interested when Richard McCaughan from Moores Animal Feeds recommended he start using one.

“Richard was adamant that all his customers that used it, never questioned its use given the difference they saw,” added Edwin. “I asked him how can you actually tell the difference and of course he said just give it a go and you will see.”

So William and Edwin agreed and decided to use Sil-All 4x4+ on both their first and second cuts.

Edwin explains: “Richard recommended this product given the results he had experienced and outlined what we should expect and how straight forward it was to use. It wasn’t an easy decision given the market conditions at the time, however we looked upon it as a long-term investment with the aim on getting more from our forage and hence cutting feed costs later on.”

Mark Crawford, from Farmcare Products, was invited out to look at the results this week.

William admits he wasn’t expecting the results: “I have been making silage for over 40 years and had never used an additive. We started using Sil-All 4x4+ last year I can definitely say we have never had as good a silage. There was been a lot less waste, the clamp is a lot more stable, the analysis is better and the cows love it. And most important we have been able to save quite a bit on anticipated feed requirements.”

So how does Richard explain this to his bosses trying to sell more feed?

“We take the approach that the more a farmer gets from their forage, the more profitable they will be and the better customer they will be in the long term” he explains. “We aim to work with the farmer helping them to become more efficient and manage their output costs, therefore strengthening our relationship and long term business.”

Mark Crawford highlights how an assessment at their clamp supports their claims.

“The first thing you always see is the lack of waste in the clamp, on the surface and shoulders and the face. The clamp here is in excellent condition with only one shoulder showing a little damage due to water ingress. Consolidation has been excellent (even with the fact it is a relatively long chop length) and there are no contamination issues on the face. Face and feed out temperature is stable and the smell has a lovely sweet and sharp scent. At the trough the cows are not sorting and cleaning up what is in front of them quickly. It was also nice to see a very settled herd with over 70% of them happily ruminating.”

Richard added: “The analysis is also very good considering the general poorer quality of silage we have seen throughout the area this year. DM was 33%, ME 11.3, D Value 70.9, Sugars 5.6 and Intake of 104. Cows are milking well and initial feed requirements are well below average.”

William and Edwin agreed: “it is nice to see a long term decision pay off, happier cows and a reduction in our feed bill. Definitely a worthwhile investment.”

Sil-All 4x4+ is a market leading inoculant originally developed by Alltech. Now owned by Lallemand Animal Nutrition it has seen continual development in terms of its quality and performance. This was recognised recently by Norwegian trials where Sil-All is the market leader.

From 2,300 samples with a DM range from 20-50%, they found that treated silage consistently showed an improved fermentation. Ammonia Nitrogen levels were lower in treated silages meaning that protein is better preserved and there were much higher levels of desirable acids (lactic, propionic) versus undesirable (acetic and butyric).

The four strains of bacteria in Sil-All are unique as they work at different rates allowing a much more efficient and controlled fermentation. The first starts quickly and as its efficacy begins to wane the second strain kicks in and so on to the third. In addition the enzymes help drive the fermentation in particular when sugars are low. Finally the fourth bacteria strain produces propionic acid which is one of the most effective agents at killing yeast and moulds and decreases fungal counts in silage (the main cause of heating at the clamp face).

It is also a very simple and stable product to use (much to the relief of contractors). It comes in either powder or liquid with tke latter being the favoured option. This allows the farmer/contractor to dilute it to anywhere between 100ml-2L per tonne application.

For more specific advice regarding your silage, how to get the most from it throughout the winter and inoculants, contact Farmcare Products on 028 6634 8469/07733 346 310.