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Ask the experts: Stray voltage

PD Editor Emily Caldwell Published on 28 February 2011

This article was originally published February 28, 2011 and featured in March 1, 2011 Extra e-newsletter: to jump to the article below.

Progressive Dairyman asked three industry experts, “What do you think is the most often missed symptom of stray voltage? Their responses were:



  • “An increase in the number of animals in the hospital barn,” Jacques Dion of Agrivolt
  • “How cows drink water; if the cows tend to lap, or dip, to get water, there is a strong possibility of a stray voltage problem,” Jerry Lush of Stray Voltage Consulting
  • “Subtle changes in animal behavior; we are often too willing to ignore small indications until it causes severe behavioral change – this is obviously too late,” Chuck Untiedt, dairy farmer, Udder Chaos Inc.

Because this article was so popular, we reached out to the same companies to ask about stray voltage and legislation. We asked Untiedt and Lush, as well as Michel Montreuil of Agrivolt and Don Petersen of the Iowa Farm Bureau Federation, the following questions: Is legislation an effective way to combat stray voltage? If yes, what elements does the most effective legislation contain? If not, where does it rank in terms of other effective options? Are there any programs or states that seem to be succeeding in combating stray voltage more than others? How can producers get involved?

Click here to see their responses to these questions.


Stray voltage is often misdiagnosed. Progressive Dairyman asked three industry experts, "What do you think is the most often missed symptom of stray voltage? Why?"

Click a link below to see a response from a specific expert:


Plus, read an excerpt from "Leakage current: Don't let stray voltage shock your cows."

Stray voltage, or “leakage current” as we prefer to call it, is an issue becoming more prevalent in the dairy industry.

As our industry utilizes more electronic equipment that increases the efficiency of our operations and reduces operating costs, such as variable speed drives (VSDs), electronic ballast lighting, variable speed fans and ventilation, we are actually increasing the sources of possible stray voltage.

Faulty wiring, defective equipment, bad connections and electrical arcs are also sources that may cause stray voltage on a facility at any time.

Read the full article.

Jacques Dion


Jacques Dion
Agrivolt Inc
Kansas City, Missouri

The term "stray voltage" in our view, could be better understood as "the need to monitor and manage your electrical network." When you have current flowing on your grounding network at a level that can be felt by your livestock, the result is going to be a level of "stress" to the cow.

Each cow will react differently to stress depending on her physical health and the overall demands on her body. There are obvious symptoms of the presence of unwanted current flowing on the ground network such as decreased water intake, breeding issues, production concerns or a general view that the animals are not at ease.

One symptom of stray voltage that is often overlooked is an increase in the number of animals in the hospital barn.

Of course the first reaction of the producer is to call the vet — then the nutritionist — then maybe check the milking equipment or look at milking procedures. After a great deal of frustration, someone might decide to check the electrical network.

This symptom is generally overlooked because producers first think about the management tools that they are used to dealing with on a daily basis such as the animal health, nutrition and their milking equipment. Our dairies today require that we manage the electrical network just as we do other management parameters.

As stated, current on the grounding network causes stress to the cow. We know that if you stress an animal, you lower the immune system, thus increasing the cow’s susceptibility to disease.

Unwanted current on the grounding network, aka stray voltage, from any source, on-farm or off-farm, can limit expected results from your cows and increase overall production cost and decrease profitability.

Jerry Lush

Jerry Lush

Stray Voltage Consulting
Brookings, South Dakota

(605) 695-3328

The most often missed symptom of stray voltage is how cows drink water. If the cows tend to lap, or dip, to get water, there is a strong possibility of a stray voltage problem.

The cows will not put their mouth in the water to take a long deep drink. They might satisfy their thirst, but do not drink enough to produce milk like they should.

Decreased water intake usually goes along with decreased feed consumption, resulting in lowered milk production. This symptom is most commonly missed because the farmer does not have enough time to observe how the cows drink.

The most important water that a cow drinks is directly after milking, when the farmer is busiest. It is also when the milking equipment is on, possibly causing the voltage to be at its highest level.

In large operations there are many water fountains and to observe cows drinking is difficult. Cows will gather around a fountain, and, if there is voltage present, they are already reluctant to drink. A nearby person is another distraction.

Ice around a fountain in the winter is an indication of stray voltage. Stress when drinking water can also cause increased somatic cell count.

Chuck Untiedt

Chuck Untiedt

Dairy farmer
Lakefield, Minnesota

(507) 839-3739

The most often missed symptom is subtle changes in animal behavior. Why? Because we are often too willing to ignore small indications until it causes severe behavioral change — this is obviously too late.

Abnormal change in a cow’s normal behavior may be caused by stray voltage/current. Quiet observation of the dairy animals is crucial. We all know the most common areas to look at when improving cow comfort. What we do not ask ourselves is, "Are my cows behaving normally?" and "Can it be electrical stress?"

Cows by nature are very curious and even playful; they should not be afraid, or avoid certain areas. They should drink until they are satisfied, not jerk their heads up from the waterer or constantly "sensing" the water by cautiously licking at the waterer or water.

They should eat aggressively, not leave a layer of feed on the floor. They should let down their milk after proper prepping stimulation, milk out completely with minimal unit reattachment, stepping and kicking should be extremely minimal and walk calmly in and out of the dairy barn or parlor.

Often we see very dramatic symptoms, the cows are afraid to even move their heads or ears, will not eat, run away from the waterer when the water starts flowing - to me this is like watching a "train wreck" in slow motion. We need to look at subtle changes in the cow’s behavior and not wait until you have violent reactions.

More dramatic concerns are when the nutritionist is not seeing normal response to nutrition changes, the veterinarian is seeing cows that are not responding appropriately to treatment and vaccination protocols and multiple cows are kicking at the same time. PD

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