From 25 milliliters of teat dip to 12 milliliters. From two manual positions to one. These are the improvements VDS Farms in Fulton, Michigan, made after installing pre- and post-milking robots in their 40-stall rotary last fall, according to parlor manager Stijn Brebels.

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The automated sprayers are manufactured by Green Source Automation (GSA) in Ceres, California. The company installed their first robot eight years ago and currently has dozens in operation domestically and abroad.

The pre-milking robot uses electrolyzed water to disinfect the teats and brushes to stimulate milk letdown. VDS Farms can make their own diluted chloride solution using the robot, which saves on costs from the peroxide used previously, Brebels says.

The robot applies post-milking dip via spray using a robotic arm.

Both robots use a dual-camera system that can see in real-time 3D and analyze at a rate of 20 times per second to identify the location of teats, according to the company’s website.

“Automating the processing of a live animal in a real-world setting is the most challenging type of automation there is,” says Brad Tripp, sales manager for the company. “The solution has to be able to account for and respond to constantly changing variables in real-time.”

Along with VDS Farms, they conducted a study to compare pre-milking teat cleanliness by manual and automated disinfection. They used an adenosine triphosphate test to measure actively growing micro-organisms on the sidewalls and openings of the teat.

On average, there was a 49 percent improvement when using the pre-dip robot for the front teats – which are more difficult for humans to reach – and a 27 percent improvement for the rear teats.

Together, the robots have allowed VDS Farms to maintain its somatic cell count at 86,000.

Because the brushes on the pre-dip robot are a little rougher than manual stimulation, it did take the cows longer to adjust to this machine than the post-dip robot, Brebels says. The mechanisms have also broken a few times, unlike the post-dip robot.

Without the dip spillage observed in manual post-milk dipping, the farm is able to cut their dip usage in half. This decrease can be advantageous as it allows producers to invest in a higher-quality dip, such as those intended for cold weather, says Dr. David Reid of Rocky Ridge Dairy Consulting.

VDS Farms runs their rotary at 11 seconds per stall. The robots are capable of operating at under 5 seconds for rotaries with 100 or more stalls, Tripp says.

The Michigan dairy plans to install a 50-stall rotary at its second farm equipped with the two robots, Brebels says.

Management plays a key role in ensuring that automatic sprayers function optimally, says Mark Futcher, DeLaval’s market development manager. This includes keeping udders, long hairs and tail switches free of organic matter so the camera can properly identify teats.

For systems that use cameras, a device is required on the floor of the rotary stall to position the cows’ rear feet and legs uniformly. This is especially important for small-framed cows and those with mild lameness.

Systems that use lasers can have trouble identifying teats on udders with abnormal conformation, says Reid. Some farms keep a second parlor on hand for these cows to be milked and manually cleaned.

Aside from the robotic arm used at VDS Farms, automatic sprayers on the market have a number of different designs, each with their pros and cons.

One of the first automatic spray systems developed required cows to walk over a fixed sprayer as they exited the parlor, says Ian Ohnstad, director of the UK-based consulting company The Dairy Group. While these systems could be applied to many different parlor types, chemical usage tended to be high and coverage less than ideal, he says.

Dr. Peter Edmondson, formerly a member of the Shepton Veterinary Group, documented the failure of such a system on a British 135-cow dairy in the March 2012 issue of Veterinary Record. Because the system had a single jet, it could not reach the outsides of the teats, resulting in visible teat coverage of only 10 to 20 percent.

There was also a delay of up to one-and-a-half minutes from the time that a cow finished milking to when it was sprayed. In a nine-month period, herd somatic cell count increased from 91,000 to 554,000 per milliliter of milk.

“Exit race sprayers rely on a cow walking at a set pace and having a certain udder conformation to ensure that the jetter sprays the disinfectant at the correct time,” Edmondson wrote. “No allowance can be made for lame cows, animals which walk slowly, excitable animals which may rush through the race, cows which do not walk centrally over the jetter, cows with high or low udders, or pendulous teats which splay sideways due to a rupture of the median suspensory ligament.”

Another automated system by the British company Ambic, called Locate ‘n’ Spray, uses stationary blocks equipped with up to eight nozzles that lie between cows’ legs in each rotary parlor. Producers can apply different pre- and post-milking disinfectants with one device, Ohnstad says.

A study conducted in 2014 by Ambic and The Dairy Group found that this device, on average, hit 97 percent of teat ends compared to 94 percent with manual vacuum sprayers. This coverage was also more consistent than with manual efforts.

Between 61 and 90 percent of teat barrels were covered when using different spray durations that required between 18 and 67 milliliters of disinfectant, respectively.

“The associated benefit of time saving in the parlor allows better targeting of labor, benefiting udder health and milking management but partly offset by higher chemical consumption,” the study authors concluded.

Whatever system producers choose to invest in, the main goal of automation is to save on manual labor.

“I think we all agree that labor is becoming probably one of the biggest issues in the dairy business – difficulty finding good people, difficulty keeping them,” Reid says.

Producers would likely choose a robot with reasonable coverage – even if it used more disinfectant than manual methods – to avoid labor costs and issues, he says.

“It is never going to make a worker’s comp claim, and it is never going to have issues showing up to work.”

Brebels estimated that VDS Farms will recoup its investment costs in two or three years given their savings on labor. The dairy also saved money by installing the robots on an existing 27-year-old rotary.

Future robotic teat sprayers should focus on improving teat coverage and reliability as well as lowering chemical usage and running costs, Ohnstad says.  

PHOTO: This robot applies post-milking dip via spray using a robotic arm. Photo courtesy of Green Source Automation.