My brother-in-law called me several years ago. He was concerned that his dairy herd was not eager to enter the milk barn which was highly unusual. He checked to see if the feed was bad. Not so. So he began forcing the herd into the barn each day. Milk production was way down and the cows all kicked and bucked when in the chutes. On the day he called me he commented that he got shocked when he touched the stainless milk storage tank. So I grabbed my meter and drove to his milk barn. I walked in wearing my rubber boots (standard clothing for the average dairy farmer) and carefully tested for voltage from tank to other equipment. When I placed my lead wires on the tank and on metal milking equipment piping I got 30 Volts AC. As it turns out, he had sent his evacuator motor off for repair and reinstalled it himself. He failed to ground the motor case properly which set up the voltage problem. He had been shocking his cattle for about two weeks. It took him most of a month to get the herd to approach the milk barn unassisted! (milk cows usually are very eager to enter the barn. During the milking process they are fed a sorgum rich feed that is very very tasty to them!!!)