Selecting the right maize variety will help boost milk from forage and reduce costs per litre.
This is the message from Limagrain’s Richard Camplin, who suggests a focus on variety selection could increase the benefits of feeding maize.
“As dairy farmers come to grips with lower milk prices every cost will come under scrutiny with the aim of increasing efficiency,” says Mr Camplin. “Forage is key to dairy margins so anything which can increase production from forage should be investigated as a priority. A close focus on maize variety choice is one area which could deliver a positive response.”
He says the objective with all forage crops must be to maximise the nutrients grown and harvested. With maize, which is principally an energy crop, this means maximising the yield of ME grown and this is greatly influenced by the variety grown. He says there is a considerable range between varieties in ME yield per hectare which is a function of dry matter yield, starch content and cell wall digestibility.
“Many farmers grow the variety they grew last year. While this is a safe base it means you miss out on the advances being made in plant genetics which are having a big impact on crop potential. Specifically we are seeing improvements in energy content and energy yield which, after all, should be why farmers grow maize.”
He stresses the first criteria when selecting a variety have to be agronomic, with varieties shortlisted based on their ability to grow well in the farm’s local location and specific conditions. “It is vital the variety grown will reach maturity at an appropriate time and can actually be harvested. There is no point growing a high yielding late variety if there is a risk it will not get into the clamp.”
Mr Camplin says to maximise energy, farmers should then select a variety from the BSPB/NIAB list with a high energy yield per hectare but warns this does not mean just selecting the highest yielding variety.
“A balance needs to be achieved between quality in terms of dry matter, starch and cell wall digestibility and physical yield. You want to achieve a good energy yield but at a high energy content. It is vital feed quality is not reduced when searching for maximum energy yield.”
He explains the total energy available in maize is in two forms. First, there is the starch found in the cob which accounts for around half the total energy harvested. The rest is found in the digestible fibre present in the stem and stover, the availability of which depends on the digestibility of the cell wall. The more digestible the cell wall, the more of the nutrients and energy held there are available to the cow.
The benefits of increasing energy yield from a variety with good energy content can be considerable and as growing costs are basically the same between varieties this will reduce cost per unit energy from forage.
“On a less favourable site, the top early-maturing variety on the list, LG Ambition, will produce almost 11,000MJ more energy per hectare than the average variety on the list while producing a high quality forage per kgDM. The extra energy could be used to increase total production or to produce more of the current yield from forage, allowing a saving in purchased feeds (see table).
“For a typical farm growing 20ha of maize, this ‘free’ extra energy would produce approaching 40,000 additional litres. Alternatively it could allow a reduction in purchased feed use of around 20 tonnes. Either way, margins will improve.
“I can think of no other decision a farmer can make which will involve no additional cost, effort or time which will increase production from forage and potentially reduce costs per litre. Paying attention to energy yield will be one way dairy farmers can increase efficiency simply and cost-effectively and help mitigate the current lower milk prices,” he says.
|Per ha||Benefit for 20ha crop|
|ME yield from LG Ambition (MJ/ha)||192,898|
|ME Yield from average variety (MJ/ha)||181,979|
|Benefit of growing LG Ambition (MJ/ha)||+10,919||+218,380|
|Extra potential milk production at 5.5MJ/L||1,985 litres||39,705 litres|
|Milk value at 25ppl||£496||£9,920|
|Potential concentrate saving at 11MJ/kg fresh||992kg||19.852t|
|Potential concentrate saving at £225/t||£223||£4,466|