Transitioning to an automatic milking system can often be challenging in terms of feeding from the start, and feeding may require more time and effort than a conventional system at certain stages. The automatic milking system is basically a computer feeder that milks cows. If you do not understand, adapt to or believe in this system, your success rate will be limited and you will certainly be frustrated.

The key to understanding and embracing feeding in a robotic system is by thinking about two things at the same time: what is fed in the robot and what is fed out of the robot.

Learning about how the two different feed delivery methods drive cow behavior, affect milk production and cow health, and must work together to achieve nutritional balance will help your transition to an automatic milking system.

What do automatic milking herds eat?
What goes in the robot is most commonly a feed pellet. What goes in the feedbunk is the PMR. PMR is a common term used in the robotic industry and stands for partially mixed ration. This terminology was adopted to reflect the fact that what is in the feedbunk is no longer a TMR.

Robot feed
The robot feed can represent between 10 and 35 percent of the cows’ dry matter intake per day and must be a palatable enough product that cows will eat it without hesitation. As the automatic milking system is a feeding system that milks cows, cows must love the taste of the feed to keep them coming back for more.


A pellet is the most common and accepted feed for an automatic milking system. In addition to palatability, the second-most important part of feeding in a robot with pellets is hardness. Improving hardness is important for desirability, but it’s a fine balance not sacrificing the palatability of pellets when trying to improve hardness.

Basically, the pellet must be palatable and reasonably hard, but taste comes first.

There are some dairies successfully using non-pellet feed or other products in the automatic milking system, but this is a very small portion of automatic milking systems in North America. If you think you would like to feed something other than pellets, it is advisable to take the safe road and work through transitioning and start-up with pellets.

Pellets will allow for good fast intake and keep consistency in the robot. The cows are going through a lot of changes during transition, so offering a consistent and desirable feed will help get them to the robot more quickly, whereas using other feed could stall or vastly disrupt transition.

As time passes, it may be possible to experiment with other things slowly at your own choosing. Over the past year, some dairy producers, working closely with industry experts, nutritionists and consultants, have seen some success using certain grain mixes, roasted beans and corn gluten feed pellets.

It must be noted that these producers generally take it slowly and work with other professionals when experimenting, as to not hamper intake at the robot and cow nutrition and health.

dairy cow in a barn

Suggested ranges on robot feed:

  • Feed rate: 5 to 20 pounds per cow per day based on production or flow system
  • Crude protein: 18 to 27 percent
  • Starch: 25 to 40 percent (Watch these levels if cows receive large pellet amounts.)
  • Fat: 4 percent or less and avoid rumen-protected fats in pellet
  • Limited minerals and vitamins
  • No unpalatable ingredients such as blood meal, meat meal, etc.

Keep it simple; don’t overcomplicate the robot feed system. Give the cows something they want and crave to eat every visit to the automatic milking system.

PMR (partially mixed ration)
As I mentioned, the biggest difference between automatic milking system herds and conventional is that you are using two feed types in different locations, but you have to think about these two feed delivery methods at the same time. It all boils down to the fact that you still have a milking cow, and its nutritional requirements must be met properly.

The suggested range in the industry is to start by balancing the PMR for 15 pounds of milk below the herd-average production. In lower-production herds, this can be very difficult when forages are very good quality, but it is important to adjust the system to protect the cow’s nutritional balance.

The PMR can be made up of forages, base mixes or corn and can consist of similar ingredients as a TMR but adjusted for the fact that the robot feed will provide the balance of the milk production capacity of the cow. The bunk-fed PMR and the pellet feed in the robot together make a complete ration.

Suggested ranges on PMR:

  • Keep PMR at least 15 pounds below herd production to get best results on cow behavior to the robot. Energy demand and palatable robot feed will then drive cows to the robot.
  • High starch or high fats in the PMR will have the greatest negative impact on cow behavior to robot. Keep the starches and fats in check.
  • High fiber levels can fill cows too much, decreasing their drive to the robot and decreasing their overall dry matter intake; watch forage NDF.
  • Decreasing PMR energy will increase cow visits to the automatic milking system.
  • Increasing energy can decrease cow visits to the automatic milking system.

Look at your total nutritional plan before you start feeding in the robot. Work with a nutritionist or industry expert of your choosing to help determine what should work best for your herd.

Different flow means different strategy
In directed-flow herds, most of these guidelines will still hold true, but you can be a bit more flexible. Your PMR can have a much higher milk support level in a directed-flow. Good rumen health and high dry matter intake will be the primary driver of the directed-flow herd.

The beauty of the AMS system: It helps you understand your cows
The cows in the herd will tell you what they need and don’t need based on the behavior and production on the AMS.

That is the beauty of the system.

Since we are asking cows to make many more decisions on their own in automatic milking system barns, we can learn and teach ourselves a great deal about what cows really want and not what we want them to have.

Plus, we are given multiple tools and tons of information within the automatic milking software to verify the data and help us make our decisions based on what the cows really want on a daily, weekly and monthly basis, and continue to adjust accordingly as things change.

The best advice is to use your past experiences and knowledge to guide you in the right direction when it comes to automatic milking system feeding. Finally, use industry experts and others using automatic milking systems to gain knowledge and to guide you in the right direction and help answer any questions that may arise. PD

Paul Berdell is a consultant helping dairy producers transition to robotic milking and has more than a decade of experience with robots. His company, Robotic Milking Integration Solutions, works alongside dairy producers around the world. Berdell can be reached by email.

TOP: Pellets are the most common feed type in the automatic milking system and are the best for startup and transition feeding.

MIDDLE: Whatever is fed through the automatic milking system should be prioritized for palatability (taste) and then balanced with the rest of the ration for nutritional needs. Photos by PD staff.

paul berdell

Paul Berdell
Robotic Milking Integration Solutions