Milking dairy cows with robots

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. Surveys have shown that one of the most common reasons is labor (flexibility, perhaps more than labor costs) and lifestyle or quality of life for herd owners and their employees.

Feeding management is key to success

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 the concentrate pellet fed in the robot box, especially in free-flow cow traffic farms. This balance can be challenging.

• A palatable feed offered in the RMS milking box is one of the motivating factors for cows to visit the RMS, with the other one being the availability and quality of the PMR in the feed bunk.
• Some farms feed more than one type of concentrate pellet in the robot box, such as a high-production pellet for their earlier-lactation cows and a late-lactation pellet that is less expensive.
• There is a reduction in the amount of feed offered in the robot box, especially in guided-flow cow traffic farms.

In free-flow cow traffic farms (where cows have continuous access to the 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 and one-way gates into the RMS box area), the PMR was balanced at 8 to 15 pounds less than the average. We find that the PMR, especially in guided-flow farms, more closely resembles a conventional TMR (totally mixed ration).

Feed quality

Forage quality and consistent dry matter in the PMR are really important. Nutritionists in our survey indicated that the palatability of the pellet and consistent PMR mixing were the two most significant factors affecting RMS success. Consistency is the key.

Farms that achieve consistently high production have the following attributes:

• Consistent PMR dry matter
• Consistent mixing and delivery of the PMR
• Consistent feed push-ups
• Consistent and frequent cow fetching
• Consistently high visits by fresh cows
• Highly palatable PMR
• Highly palatable, consistent, high-quality milking station feed

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

There are clear advantages to milking cows with robots, but also challenges in maintaining udder health.

One advantage of RMS is that quarters are individually milked and detached, reducing 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.

Teat prep

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 four 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.

Mastitis ID 

Another challenge relates to the 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 infectious organisms are present in the herd, there may be special add-on equipment (e.g., steam cleaners) that can help.

Steps to help reduce udder health problems

• It is essential to get cows to visit the RMS milking station regularly. If cows have a very long milking interval, milk leakage increases, and these cows are at higher risk of mastitis.
• Keep the barn and stalls clean. The RMS cannot distinguish between dirty and clean udders; cows must enter the RMS unit with a lower bacterial load.
• Keep the milking units, the robot and the area around the robot clean.
• It is also essential to fine-tune RMS settings for optimum performance on a routine basis and adjust the machine for the barn and bedding type. Default values might not be adequate. Work with service providers in this process.

Adjusting the pre-stimulation time (for rapid milk letdown) and teat-drying time, plus adjusting equipment for breed, teat size, and udder shape, can help reduce problems. Develop a system to rapidly identify failed cows. Research shows that cows/quarters with incomplete milking are more susceptible to infection.

Knowledge of 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 optimize RMS use.