While removing silage from the clamp can seem like a simple job, feed equipment experts claim the choice of implement can be key.
Jane Carley reports...
A silage clamp is an economical and convenient way to provide quality forage to housed livestock, but even if the utmost care is taken when making and sealing the clamp, expensive losses are still possible when feeding out the material.
From buckets and shear grabs to block cutters and self-propelled mixers, methods and techniques for removing silage from a clamp can vary wildly, as can the effect each of these methods has on silage losses.
While each method has its own pros and cons, the main aim is achieve a neat, airtight clamp face.
However, while some methods achieve this very well, their time and cost needs to be weighed up against circumstance and budget restrictions.
James Brough, Keenan UK and Ireland general manager , says losses are very farm-specific but they can be significant when buckets are used to rip silage from the clamp.
In this instance, losses are physical and nutritional.
He says: “Crevices are created when the bucket lifts the silage out, often 0.25-0.5 metres back into the face. This allows air to penetrate the clamp and increase aerobic activity.
“Along with the sugar and lactic acid in the clamp, air feeds the yeasts and moulds, which in turn break down organic matter, increasing the ash content, leading to physical spoilage and lost milk potential.
“When collecting silage from the clamp to feed out, the aim is to minimise disruption to the integrity of the clamp face, avoiding air ingress which will lead to increased aerobic spoilage issues and nutritional losses in the clamp.”
USING A SELF-LOADING MIXER
IN an ideal world, Mr Brough suggests the most efficient way to transfer silage from the clamp to the wagon, in terms of time, reduced waste and cow performance, is to use a selfpropelled mixer wagon with a self-loading facer/header.
He says: “This will neatly deface the silage clamp while protecting the forage structure for optimal rumen function, across all forage types.”
There are a number of benefits to using a milling head, he adds.
“Quicker travel across the face each day and further protection of the clamp face structural integrity reduce aerobic spoilage issues across the silage face,” he says.
“There is also less stress on the mixer wagon as all forage is broken up before entering the mixing chamber.”
Advantages extend to feed quality too.
“Multi-cut grass silage systems have much leafier forage which must be handled and processed with care to avoid damaging forage structure.
“The milling head cutter - if designed correctly - aids this process, so there is less risk of silage clumps in the ration presented to the cow.
“Rations are also more accurate as when the mill head is attached to a self-propelled machine, the exact amount is taken from the clamp face without waste.”
An alternative would be to use a rotating silage facer and then bucket the silage into the mixer at, or very close to, the clamp face, Mr Brough says.
“There is a compromise between some processes in terms of speed when choosing attachments that will significantly reduce wastage, but result in more time needed for that step in the feeding programme,” he says.
“The choice also depends on the availability of separate tractors with loaders and telehandlers.”
MOST problems are created when the crop is ensiled, providing a challenge to manage at feed out.
Spend time at clamping to ensure adequate compaction.
Uncover the top as little as possible each time. Daily may be unfeasible on most units, but aim to uncover no more than three days’ worth.
Work across the silage as quickly and neatly as possible.
Protect the structural integrity of the silage face by using a purpose designed attachment, rather than ripping material out with a bucket.
THE smaller the face, the easier it is to reduce secondary fermentation and spoilage which can reduce feed intake, suggests John Molton of BvL, which supplies mixer wagons and loading equipment.
He says: “The block cutter is the ideal tool for this, and they are proving increasingly popular for units using feed kitchens which may need to store blocks of material for 24 hours before feeding as the material is less likely to spoil than if it had been torn out of the clamp.
“They are the choice of the more professional farms which aim to get more out of their silage.”
However, he adds that operators need to be prepared to use and maintain block cutters well.
“Ideally one driver should be dedicated to the job, and it is not ideal for large herds and multiple drivers,” he says.
“Technique is important – you need to approach the clamp straight and let the block cutter do its job.”
Mr Molton points out that the implement is effectively a hydraulically driven knife, so hydraulics and blades need to be looked after and kept away from stones.
“Many of our customers like to keep their old block cutter as a back up when buying a new one,” he says. “Aim to replace the blades every year so it can continue to bite through the material.
“There are also a range of combs and rakes available which are good for maize but struggle on grass silage.
"Comb heads are used on BvL’s self- propelled feeder wagons, raking the material out rather than chopping it, which improves the quality of the mix.
“However, self-propelled machines can be hard to justify with milk prices as they are.”
ALBUTT offers a wide range of shear grabs and sales director Robin Normington says: “Shear grabs can leave a very clean face, but the wider the cut the better. Do not aim to go deep into the clamp.
“Albutt grabs are designed to be wide and shallow for this reason.”
A good cutting action depends on the quality of the blades and the geometry of the shear grab, he adds.
“The grab should handle all materials equally well, although dry forages are more difficult to cut,” he says.
“Compared to a defacer, grabs cut and load in one operation, avoiding the need to rehandle the forage and cutting cycle times.”
Choosing the right blade material can reduce the maintenance requirement, he says.
“We swapped from using hard faced material to Hardox, which retains the sharp edge for longer and resists damage, so all that is required is greasing.”
Shear grab size should be matched to the loader, Mr Normington adds, with three ranges available from Albutt to go from tractor loaders to large wheeled loaders, the latter employed by the largest dairy units and anaerobic digestion plants.
BvL’s Mr Molton points out that while there is a wide choice of shear grabs available, the quality varies.
“It is important not to overload a shear grab – if the jaw cannot shut to the tines, it leaves a ragged face.
“A good operator can get very good results with a shear grab, but they need to be sharp to work well. Never use the grab for other jobs as that will damage it.”
The aim, Mr Molton says, is to get across the clamp face quickly, but it should also be done properly.