French researchers have shown that it is possible to combine robotic milking and grazing without adversely affecting milking frequency.
As in the UK, robotic milkers are becoming increasingly popular in France, with more than 3,000 units already installed, says Valerie Brocard, researcher at the Institute de I’Elevage. But there is a trend against grazing.
On average, 92% of French cows are grazing, while on farms with robots, it is much lower at 48%. “There is a trend towards less grazing after purchasing an automated milking system,” she says.
However, there is increasing pressure on farmers to be more nitrogen sufficient and rely less on imported soya. “It is, therefore, important to keep some grazing in these [automatic miking] systems.”
The same question is being asked in other European countries on how to combine grazing and robotic milking. And this is the aim of the EU-funded Autograssmilk project, involving researchers in Ireland, France, Germany, the Netherlands, Denmark and Sweden.
One of the partners is the Institute de I’Elevage, which has been researching solutions at its Derval experimental farm in western France since 2010. The project also involves a network of 20 partner dairy farms across France.
The pilot farms have an average herd size of 53 cows and yield of 8,000 litres with a grazing area of 0.4ha/cow.
The Derval experimental unit has three paddocks in a simplified rotational system. The furthest paddock is 400m away from the farm and cows are buffer-fed maize silage, with the amount according to grass availability.
After four years of trials, Ms Brocard says it has become apparent that a timetable is important when 100% grazing to help cow traffic.
Cows have free access to grazing from 8am to 6pm. All cows are fetched inside once a day at 6pm and housed until 9pm. This allows for AI’ing and other activities to be carried out. They can go back to pasture after 9pm after being milked in the robot.
With 72 cows needing milking at least twice a day, you need at least 30 milkings at night, so the schedule helps achieve this, she explains.
Grass intake is weather dependent, but the pilot farms achieved grass intakes of 700kg to 2t a cow a year, which compares well with the French national average of 1,500kg.
“Some are achieving this level [average] and some are getting even higher. It shows if you have grazing area and motivate cows, you can get a good level of grazing.”
Milking frequency was unaffected by grazing, with 100% grazed cows being milked 0.12 time less a day at Derval and 0.2 times less on the pilot farms.
“Milking 0.2 times less a day shows there is little effect on frequency,” she says.
Milk yields were reduced by 0.7kg a day on the experimental unit and 1.4kg on the pilot farms. “This was related to a reduction in concentrate intake rather than grazing itself.”
However, the benefits of grazing in terms of reduced feed costs were seen across the farms.
In conclusion, combining robotic milking and grazing is possible and is a case of motivating cows and finding the right traffic.
The project was presented as part of a series of DairyCo webinars.