As long as we allow our power companies to undersize neutrals and use the ground as the fourth wire we will have these problems. Non-liner loads from switching power supplies is only going to get worse, and the untended infrastructure can not handle the neutral loads. This requires it to go back to the substation / generator through the ground. I can't prove to you that these things are caused by stray voltage, but I can tell you they will go away by correcting a stray voltage problem. Dairy farms get better milk production, less animal deaths, less mortality rates with calves, less still births, less downer animals, less mastitous and associated problems. In people, better sleep, less cronic fatigue, fibromyalgia and in some a few diebeties and heart problems. Power Companies are not all to blame. We have problems with equipment and wiring in our homes, farms and factories. Many of these problems are caused by unqualified people doing installations or using improper wiring methods. Tracking these problems is time consuming and expensive, because alternative paths for current will change with conditions. I could go on for some time about this problem.