Equal attention needs to be paid to concentrate fed though the robot and the ration at the feed fence to maximise milking efficiencies and performance on robotic milking systems.
That was the message from Prof Trevor DeVries, of University of Guelph, speaking as part of a Mole Valley Farmers research and development webinar for its nutritionists.
He said: “It is not just the feed in the robot, but the feed at the feed bunk which pays as important a role for promoting voluntary milking visits,” he said.
“We need to be thinking about these feeds as a whole rather than thinking about them as two separate components.”
Provide quality concentrate and forage
Prof DeVries said the concentrate fed through the robot needed to be high quality and palatable and formulated to match the type of cow traffic system operated.
“Ultimately, this acts as an attractant to encourage cows to visit the robot. Forage quality is also essential and will help maintain consistency of eating behaviour at the feed bunk, including frequent meals. All of these factors influence the number of milking visits to the robot.”
Be realistic about allocations
He added that it was a good idea to determine whether cows were really receiving their daily allocation of feed through the robot.
He said: “This will be influenced by factors such as dispensing rate, meal size, time in the robot and how fast individual cows can eat.”
He explained that some cows could eat concentrate at rates up to 400-500g/minute for around seven minutes. However, the average consumption rate was – 250g/minute.
“If a cow is milked for around seven minutes, she can only eat 1.8kg per milking on average. For systems targeting three robot visits a day on average, the average cow will be able to eat about 5.4kg per head per day at the robot.
“This is a good average target to aim for. The amount fed to individual cows can be altered above and below this depending on their yield and stage of lactation.”
Consider the type of cow traffic system operated
While all cow traffic systems can work well when managed correctly, Prof DeVries said there were different considerations with each set-up.
“For free access systems, the main impetus for the cow to visit the robot is the feed that is provided at the robot. This means that a palatable, high quality concentrate is essential.
“The partial mixed ration [PMR] provided at the feed fence would typically be balanced for 80 per cent of the herd’s average production to encourage robot visits.
“Recommended feeding rates of compound fed through the robot are generally between 3-8kg per cow, averaging 5.5kg per cow per day.
“In ’milk first’ guided systems, the PMR available on the other side of the robot acts as the main motivator, rather than the robot concentrate. This means the PMR should be balanced closer to the herd average.”
Typically, Prof DeVreis said this equated to an average of 1.5-3.5kg of concentrate being fed through the robot.
“The feeding rates should be set on an individual basis taking into account herd yield, days in-milk, forage quality and farm targets.”
Be careful when changing concentrate levels through the robot
Prof DeVries said changing the amount fed through the robot would have an impact on the amount eaten at the feed fence.
Some studies had shown that for every 1kg per cow per day increase in the concentrate fed at the robot, PMR dry matter intakes could reduce by the same amount, or more.
This, he added, highlighted the importance of understanding dry matter intakes (DMI) and not limiting DMI by how cows are rationed.
Make sure feed is always available
Robot visits are linked to when the PMR is fed out and is a factor which influences all housing systems, not just guided ones. And, Prof DeVries said in order to maximise the efficiency of the robots, milking visits need to be spread throughout the day to limit queuing.
“Feeding out regularly and pushing up the diet will ensure feed is always available and will help the cow’s time budgets,” he added.