Maximising the value of home-grown forage was the topic of discussion at a recent workshop at Rothamsted Research’s North Wyke facility in Devon, writes Ruth Wills.
WITH strong social and economic pressures from buyers and supermarkets for cows to be grazed longer, farmers needed to get to grips with increasing their milk from forage figure.
This was the message from Tom Chamberlain, of consultancy company, Chalcombe. He explained his company’s GrazeMore project looked at addressing the frustration of high yielding cows milking poorly when grazing.
He said: “Grass is half the cost of silage and silage is half the cost of concentrates.
“If we can increase grass intakes we can increase profitability.”
Mr Chamberlain studied a herd of 200 cows in the summer of 2017. After milking at 7am, cows were grazing happily. By 8.30am they had eaten the best of the grass and were beginning to make their way back over the field.
By 11am they had just about given up and they were not due to come back in for milking until 4pm.
Clearly, if cows were not grazing between 11am and 4pm this could be seen as a waste of time – and when they were offered a new area of grazing they rushed to it.
Mr Chamberlain said: “If you offer cows new feed and they stampede to it, they are hungry.”
Mr Chamberlain began investigating holding back a part of the field with a controlled gate for additional grazing.
He used GPS collars and accelerometers and measured activity with long-range wide area network technology.
This sent information in real-time to the cloud and back to the farm, where it could automatically open the gate.
On a farm using the technology with a group of 58 cows, Mr Chamberlain found that cows were grazing at 9am, were in a huddle at 10.30am, and by 12.30pm, were grouped more tightly.
At 12.40pm the information triggered a gateway opening and by 2pm the cows were intensively grazing in the new paddock. They spent an additional two hours or more grazing instead of standing.
While further investigation is required, the study showed that feed intake increased by 1.5kg dry matter.
This could lead to increases in yield of about three litres/day, and Mr Chamberlain estimated this could be worth an increase in net income/cow/day of 86p.
However, the availability of grazing and labour considerations needed to be taken into account particularly in the absence of automatic gates.
WHILE the concept of mob grazing is a familiar one, there is probably less known about cell grazing (also known as ‘technograzing’).
Dr Sarah Morgan, scientist at Rothamsted Research, explained cell grazing was a form of intensive, rotational and time-controlled grazing management system.
Introduced to the UK in 2016 by Cornish-based company Precision Grazing, there were about 200 hectares (495 acres) of technograzing in the UK now, used for dairy, beef, sheep and deer.
She explained the cell grazing system at Rothamsted used a bespoke electric fence and water supply.
An area of land had been divided into ‘lanes’ and then sub-divided into individual cells.
The number of cells allocated and the rotation time depended on your predicted grass growth and quality, as well as ground conditions and the required liveweight performance.
Technograzing used a front and back fence, as well as a safety fence. If the front fence broke the animals could not go too far, minimising the risk of the cows eating grass that they were not supposed to.