Mitigating high-dry matter in maize forage has been key to improving margins for one Derbyshire-based herd. Using an inoculant offers better silage quality and financial returns.
TEXT STUART BOOKER
While much of the country has seen milk yields fall through the winter, due to the difficult spring and summer, one dairy business has managed to buck that trend on a system where home-grown forage can make up to 60% of the diet.
A combination of careful adjustments to the diet and good management, alongside the use of a specific bacterial inoculant, has seen Adam Sills, who runs a 442-cow herd near Ashbourne, not only maintain yields and quality but also increase them.
In a good year maize typically makes up around two-thirds of the dry matter of the diet, and having grown or had grown for him just under 100 hectares this year, that would have been the plan. But with the earliest crop coming off on October 26, and the latest mid-November, everything was harvested late. One of the main problems with dealing with that was the range of quality.
“This past year has been a challenge and although we made ration adjustments we felt the maize was letting us down,” says Adam.
High lignin
“Maize silages across the UK contain more lignin and it is difficult to access energy from this fibre,” adds Kite Consulting’s David Levick, who works closely with Adam.
While his maize crop, variety KWS variety CITO, averaged 39.5 tonnes per hectare, dry matter was high, ranging from 38% in one clamp to more than 45% in another.
“With the average around the 40% mark, it was too high. There was a vast range of quality, with some good but extremely dry, and some very different in terms of the fibre and starch content and digestibility. It all had to be balanced accordingly,” says David.
Starch levels and fibre digestibility both determine how quickly the energy that is locked up in the forage will be available to the cow. “Once starch begins ‘hardening off’ it is difficult to access.”
Several practical steps were taken to mitigate this issue, and reducing chop length was vital. “We aimed for between 5cm and 8cm, but we also looked at the use of additives to enhance the crop’s potential,” he says.
Having first used a bacterial inoculant in 2020, initially on grass silage to address an issue where lines of slurry remained on the sward at first cut due to a lack of rain, Adam decided to treat his maize crop with SiloSolve FC.
“One of the key things that this additive does, particularly when faced with a high dry matter silage, is remove oxygen and minimise the risk of poor fermentation,” explains David. “This reduces the growth of undesirable bacteria.
“And it speeds up an improvement in maize-silage digestibility. Maize digestibility increases with time in the clamp, but using an inoculant actually speeds up that process and makes the starch more digestible more quickly.”
Maize silage: clamp-face management and using an additive reduces waste
Bacterial strains
SiloSolve FC contains a patented combination of bacterial strains that, together, scavenge oxygen from the silage, while actively inhibiting yeasts and moulds. The MC version of the product is designed for silage made during wet weather, or after a late application of slurry or nitrogen.
“The combination of using the additive and ensuring chop length was as short as possible, is speeding up the improvement in the quality of the maize as we are feeding it,” adds David.
Individual daily yields have been two litres below where Adam wanted them to be, so the milking ration was adjusted to improve it. “We added a rapidly-available sugar source and urea, in the form of Regumaize 44. This combination helped cows to digest the difficult-to-access energy ‘locked up’ in the maize,” explains David.
Waste bread was also introduced to the diet for the first time in several years and, because it is 98% digestible, it’s proved invaluable.
Adam has always made use of co-products as a lower-cost, when bought at the right time, and useful source of protein, that also helps to reduce an already low farm carbon footprint.
Ration cost
“These changes have slightly increased the cost of the diet, but we are still in the right ballpark for the milkto-feed price ratio,” he says.
Milk price for December 2023 was down exactly 20ppl compared to December 2022. But the rolling 12-month margin over all purchased feeds dropped by just 7.89ppl. That said, this 7.89ppl still equated to a herd margin reduction of close to £230,000.
“But we are actually performing better,” says Adam. “Crucially, we have not been losing litres, which is key to our system, despite the national lower output figures. We are achieving these results by using forages to the best of their capability, and making it economically viable to maintain litres.”
The herd’s latest milk quality results have also been impressive, averaging significantly higher than they have historically. Milked three times a day, herd average yield is 11,510 litres, at 4.51% fat and 3.42% protein, which is just short of the 1,000-kilogramme target.
“In November daily yields were 34 litres, at 4.45% butterfat and 3.50% protein. Now the herd is averaging 36 litres per cow per day, at 4.77% butterfat and 3.60% protein,” says Adam.
“The key is to reduce waste, whether that is silage, coproducts or dry feed, and using a silage additive plays a important role.”