THE ROLE OF LIQUID FEED IN ROBOTIC MILKING

Most robotic milking systems can be equipped to dispense at least 2 feeds in either meal or pellet form. Dispensing liquid feed directly into the feed bowl can also be an option. Liquid feed in robotic milking is much less common than solid feeds, but it does have a place. It can change the physical characteristics of what is offered in the robot, or satisfy a nutritional requirement.

The most common product for changing the physical characteristics of the robot feed is molasses, usually in a manufactured product. It’s an obvious choice because cows like molasses. Dispensing molasses directly into the feed bowl can reduce the dust from the concentrate. This keeps the robots cleaner and the cows more comfortable. Molasses can also improve the palatability and mask the variation of the concentrate. It will encourage the cows to lick the feed bowls cleaner. Farmers have had mixed results using molasses to attract cows to the robots. Cows may come to the robot more frequently when a new product is introduced, whether that is flavoring added to the pellet, or molasses dispensed directly into the feed bowl. That effect tends to wear off after a few weeks.

Molasses products are more likely to bring cows to the robot if they satisfy a nutritional

requirement. Recent research showed increased production when early lactation heifers received molasses in robots. When a heifer freshens, her milk production goes up faster than her partial mixed ration (PMR) dry matter intake. The same is true for cows. It’s a bigger problem for the heifers if they don’t visit the robot frequently enough to get pellets to supplement the PMR. Increasing the amount of pellet per milking can overload the rumen with starch and lead to off-feed problems. Liquid molasses products provide sugar to maintain energy balance, without upsetting the rumen, until milking frequency and PMR intake catch up with milk production.

Commercial propylene glycol products are fed in milking robots, usually with the goal of preventing ketosis. Straight propylene glycol is not palatable and should not be fed in robots. Commercial products also have limitations. Propylene glycol is most effective in a single daily dose. The dose has to be large enough to increase the glucose concentration in the rumen so glucose to moves to the bloodstream. Drenching a single dose is the best way to reach that concentration. Liquid feeds in robots are controlled by feed tables. Feed tables are designed to dispense feed uniformly through the day. It is not possible to make the feed table dispense a full day’s ration of a single feed in one milking. Multiple ingredients will be fed proportionally at each milking. Propylene glycol products might prevent ketosis if they are palatable enough to motivate cows to come to the robot more frequently.

If you choose to dispense liquid feed in your robots, use the best available pumps, tanks, and plumbing for the installation. Make sure the pump you install can handle the viscosity of the material you want to dispense. Make sure the hose or pipe can handle the pressure and volume you need to deliver. Liquid molasses can have significant benefits when it gets to the feed bowl for the cows that need it. It is extremely messy to clean up if it leaks before it gets to the feed bowl.

Contact Cow Corner to learn more about the potential for liquid feeds in your robots. We can help determine which cows can benefit, and we can help with feed and feed table settings to make sure those cows get what they need.