Milking dairy cows with robots


Source: University of Minnesota Extension

Marcia Endres, Extension dairy team leader and Jim Salfer, Extension dairy educator

Robotic milking systems (RMS) are becoming more common in the USA, especially in the Upper Midwest and Northeast regions. Dairy producers choose to install RMS for a variety of reasons, but surveys have shown that one of most common reasons relates to labor (flexibility maybe more than labor cost) and lifestyle or quality of life for herd owners and their employees.

Feeding management is a key for success in RMS

Our surveys indicate that dairy producers rank feeding management as the number one factor leading to successful results with RMS.

When we feed cows in RMS, we need to consider not only the partial mixed ration (PMR) that is delivered in the feed bunk, but also balance that ration with the concentrate pellet fed in the robot box. This balance can be challenging! A palatable feed offered in the RMS milking station is the main motivating factor for cows to visit the RMS. More farms are now feeding more than one type of concentrate pellet in the robot box, maybe a high production pellet for their earlier lactation cows and a late lactation pellet that is less expensive.

We learned that in free cow traffic flow farms (where cows have continuous access to feed bunk, resting and RMS box), the PMR was balanced for 15 to 30 pounds less than the herd’s bulk tank average production, whereas in guided flow farms (where the cows are guided by pre-selection, one-way gates into the RMS box area), the PMR was balanced for 8 to 15 pounds less than the average.

Forage quality and consistent dry matter in the PMR are really important. Nutritionists in our survey indicated that palatability of the pellet and consistent PMR mixing were the two biggest feeding factors contributing to RMS success. Consistency is the key! Farms that achieve consistently high production have the following attributes:

  1. Consistent PMR dry matter

  2. Consistent mixing and delivery of the PMR

  3. Consistent feed push ups

  4. Consistent and frequent cow fetching

  5. Consistently high visits by fresh cows

  6. Highly palatable PMR

  7. Highly palatable, consistent, high quality, milking station feed

Milk quality can be a challenge if RMS is not managed properly

There are some clear advantages when milking cows with robots but also some challenges for maintaining udder health.

One of the advantages in RMS is that quarters are individually milked and detached which reduces overmilking. This can help improve teat end health. There is also less risk for antibiotic

contamination with a treated cow, as long as her ID is entered in the computer so the milk is discarded.

However, a current challenge with RMS (depending on the system) is teat prepping and post dipping. A study in Europe found that only 67% of the cleanings were technically successful, i.e., all 4 teats were brushed. However, in the best performing farm, over 95% of the teat cleanings were technically successful. Reasons for most of the failed teat cleanings were undetermined but of the known causes, a device failure in one herd and restless behavior of the cows in several herds were associated with most of the totally unsuccessful teat cleanings, whereas abnormal udder and teat structure were associated with most of the partly unsuccessful teat cleanings.

Another challenge relates to identification of clinical mastitis cases. Although additional metrics have improved detection in recent years, a few cows might still be missed. Contagious organisms can be a real challenge. Implementing regular bulk tank milk cultures will help reduce udder health problems. If contagious organisms are present in the herd there can be some special add-on equipment (e.g., steam cleaners) that may help.

What are some steps that can help reduce udder health problems?

  1. Getting cows to regularly visit the RMS milking station is important. If cows have a very long milking interval, leaking of milk greatly increases and these cows are at higher risk for mastitis.

  2. Keeping the barn and stalls clean is very critical. The RMS cannot distinguish between dirty and clean udders; therefore it is important that cows enter the RMS unit with a lower bacteria load.

  3. Cleanliness of milking units, robot and area around the robot is also critical.

  4. It is also important to fine tune RMS settings for optimum performance on a routine basis and optimize/adjust the machine for the barn and bedding type. Default values might not be adequate. Working with service providers helps in this process.

Other items to keep in mind are adjusting the pre-stimulation time (to result in rapid milk let down) and teat drying time, plus adjusting for breed, size of teat and shape of the udder. A system to find failed cows rapidly should be developed. There is research that shows cows/quarters with incomplete milking are more susceptible to infection.

The knowledge about RMS continues to grow in North America and producers’ satisfaction with the system has improved in recent years. It takes a team approach including producers, service providers, nutritionists, veterinarians and other advisors to best optimize RMS utilization.