Colleges collaborate on stray voltage research

A new research project may determine if and how lower-level stray voltage affects livestock.

David Alumbaugh, civil and environmental engineering assistant professor, will work with researchers in the College of Agricultural and Life Sciences to examine imperceptible-yet possibly harmful-electric and magnetic fields created by low-voltage current flowing through the earth.

Traditional stray-voltage research addresses the annoying electrical shocks associated with a farm’s grounded neutral system. “The more recent claims are that the electricity in fact has a pathway through the earth, so even though the farm’s electrical wiring might be correct, there’s a concern that the electricity may be contacting the animal by traveling through the earth,” says Douglas Reinemann, biological systems engineering associate professor and member of the research team.

Similarly, a cow might be standing next to a transmission line and be exposed to electric and magnetic fields, which she probably wouldn’t perceive, says Reinemann, who has researched stray voltage for 10 years. “The question is whether or not that would affect the cow’s immune system or health in any way,” he says.

During the study’s first phase, Alumbaugh will use a geophysical remote referencing method to determine what electrical currents exist in the 1 Hz to 1 kHz frequency range. (A 120-volt household outlet produces current at 60 hertz.) Then he’ll identify which are naturally occurring electrical ground currents and which are human-made.

“We’re going to be making these measurements at a variety of locations around the farm,” says Alumbaugh. “Some of them will be close to grounding points, some close to the barn, and some of them out in the pasture away from any electrical grounding points or power lines to try to determine what the level of the man-made signal is, both in the electric fields and the magnetic fields.”

After Alumbaugh determines if there are low-level currents coming from the electrical distribution systems, the next step, says Reinemann, is duplicating them in a controlled laboratory setting, in which he can screen out scores of other variables found on working farms.

He will lead an attempt to expose cattle to the type of electrical phenomena Alumbaugh observes in the field, while dairy science professor Lewis Sheffield will evaluate cows’ physiological responses to them.

The trio will use the latest biological techniques to measure gene expression as a possible indicator of cattle well-being following exposure to certain electrical events. The group also will gather more traditional and parallel data on variables such as daily water and feed intake, body temperature, daily milk production and milking duration. In addition, the researchers will record such other variables as the time and pattern of cattle standing and lying down, and the time it takes for cows to re-enter stalls after milking.

Two years ago, Reinemann conducted a similar study. Funded by the state of Minnesota, he looked at a low-level step potential in the range of about 1 volt and 60 hertz of electricity and found no stress hormone response to low-level current exposure and no effects on cows’ immune systems.

However, the current study is unique because it examines a broader range of frequencies, he says. In addition, it forges new ways to measure animal response to electrical exposure, and may make important contributions to standardizing how researchers measure such electrical events as stray voltage.

The project is funded with $350,000 provided by the Wisconsin Legislature. The UW Stray Voltage Research Planning Committee, a faculty-government committee, approved the funding.