A clement autumn has relieved pressure on forage supplies, but careful planning and feeding strategies will be key to surviving winter.
Chloe Palmer reports...
Many beef and dairy farmers will be viewing their silage clamps and bale stacks with trepidation as winter progresses to gauge whether supplies will see them through to turnout.
But there are actions farmers can take now to ensure they can make stocks last and minimise the need for sudden changes to rations.
This is according to Paul Macer, consultant with Kite Consulting, who says although the benign autumn weather had saved many dairy and beef farmers from the most critical forage shortages, there are still likely to be issues on many farms before winter is out.
He says: “It has been a very kind autumn, allowing cattle to be grazed for longer.
“Forage analysis for cuts taken as late as November from across the Midlands have shown protein levels at about 14-15 per cent and energy levels at 10.8-11 MJ/kg, coupled with good dry matters.
“Nevertheless, it is vital farmers get a handle on what forage stocks they have and calculate how much they will need going forward.”
CALCULATING FORAGE STOCKS AND REQUIREMENTS
Mr Macer offers a four-step plan to accurately working out silage stocks and feed value:
1. Calculate the volume of the silage available
Volume (cu.metres) = height (m) x width (m) x length (m) of the clamp
2. Calculate the silage density
Silage density varies according to the height of the clamp, the DM of the silage and how well the clamp was consolidated.
Grass silage densities will typically vary between 520kg/cu.m for a silage with a DM of 40 per cent plus and a clamp height of 2m to 950kg/cu.m for silage with a DM of 20 per cent and a clamp height of 4m.
Wholecrop tends to have a lower density of between 550-650kg/cu.m. Maize silage is heavier, at about 750-800kg/cu.m.
Note: if a compacter is used, densities can be up to 10 per cent higher. Then multiply the volume by the density of the clamp to give the tonnes of forage available
3. Convert to a DM basis
Use the silage analysis for each clamp to calculate the tonnes of DM available. Estimates for late cuts of baled silage can be added to this figure.
4. Calculate kg/DM available per day
Using the estimate of forage available, divide this by the number of animals and then the number of days between now and likely spring turnout or the first cuts of 2019 becoming available.
This calculation will give the maximum figure of forage DM inclusion fed over the rest of the winter. If this value is lower than the current feed rate, other options will need to be considered to make up the deficit.
Mr Macer points to reducing waste as the first step to address shortages. His top tips for ensuring silage supplies are utilised efficiently are:
■ Minimise waste by using a shear grab to leave a clean face and always remove any spilt silage from the floor as this will heat and potentially contaminate the base of the silage face.
■ Any rejected silage should be removed from the feeding area regularly to avoid contamination.
■ Only roll the sheet back as far as is necessary and keep the sheet weighted right up against the clamp edge to avoid air ingress, but take care working near the edge.
■ Consider adding straw to rations for dry cows, youngstock, low yielders and suckler cows to maintain DM intakes and extend silage supplies.
■ Where straw is added, it should be chopped ideally to lengths of between 25mm and 30mm to avoid sorting.
Mr Macer urges farmers to prioritise animals in the dairy or beef herd which are working the hardest or have the best feed conversion rates:
■ In beef herds, older, larger animals tend to consume more and have lower feed conversion rates, so consider whether they should be sent to slaughter earlier, or where appropriate, sold as stores if forage supplies are tight.
■ Prioritise pre-calvers and fresh cows in the dairy herds.
■ Consider carefully the cost implications of retaining suckler cows which are not in-calf.
WHEN SPRING COMES
THERE is a need to focus on rebuilding forage stocks during 2019, so Mr Macer says being ready to apply fertiliser to stimulate early grass growth will be important.
■ Looking at sowing a fast-growing, high-yielding catch crop on land earmarked for reseeding.
■ Consider taking an early cut and then establishing maize on part of the silage ground.
■ Make grass work for the whole season; all too often fertiliser applications are insufficient later in the season.
WHEN looking to mix silage with high fibre co-products, think about achieving the right balance of energy, protein, minerals and fibre within the diet.
■ When including higher levels of alternative feedstuffs, consistency of DM, digestibility and absence of mould, coupled with 24-hour availability and fresh water are all key to a healthy rumen.
■ Select cost-effective ingredients which encourage high DM intakes rather than necessarily targeting high energy feeds.
■ Wet succulents can be an option but are currently hard to source, generally have higher haulage costs and greater on-farm losses.
POINTS TO CONSIDER
■ Beware of diet sorting where cows will select out concentrates within the ration. This can lead to poor rumen health, acidosis and low milk butterfat. Adding water, so the overall DM of the total mixed ration is down to about 40 per cent once concentrates have been added, will reduce sorting.
■ Diets low in grass silage and with a higher content of maize or wholecrop cereal will often be short of rumen degradable protein; adding small quantities of feed grade urea to the ration can help.
■ Maintaining the correct levels of calcium, magnesium and sodium, particularly in early lactation dairy cows is critical, so where diets contain lower levels of grass or grass silage, supplementing with limestone, magnesium oxide and salt is recommended.