Cattle deaths

At the risk of stating the obvious, cow muck is likely to be reasonably conductive, not as good as salt water, but comparable to damp earth.

(and note that     manure has a high pH  here,   and  you can tell when soil was last manured by it's conductivity.)

Dry concrete is quite a good insulator at mains voltages, but as soon as it gets even slightly damp, less so.  If there was an external voltage gradient, from a buried faulty cable or fault running to a nearby earth terminal, then that voltage gradient could well appear in the building as well as outside. In some ways the slats make it more likely, as you can have one slat at a different potential to its neighbours.

However, gradients near electrodes tend to die out fast with distance - if you plant a vertical  electrode at 230V, and then stick your meter probes in nearby, such that you measure voltage to a fara way earth terminal, about half the voltage drop is within one electrode length of the top of the spike.

(If you wish to re-create this test, I strongly suggest not using full mains voltage, and not kneeling down to do the testing, and positioning the probes with it off, and then switching on from afar. )  My point is that within a few rod lengths away the surface voltage gradient has fallen to a safe level, so any such fault would have to be close.


Even though cattle have a long 'wheelbase' and are more sensitive to shock, they are not that sensitive, and the voltages likely to cause trouble are low but should be measurable on normal instruments.
Studies with current delivered from the mouth to hooves of dairy cattle in an environment which minimized contact resistance, indicated an avoidance reaction with currents of 1.0 to 4.0 ma AC. The same workers measured electrical resistance of dairy cows and determined an average value 390 ohms. Based on this work, it would appear that dairy cattle can "sense" currents of 1.0 to 6.0 ma AC and demonstrate a mild avoidance reaction at these levels. Using a 390 ohms resistance value, this translates to a threshold sensitivity of 0.4 to 2.4 volts.


from a Canadian paper   where common practice is to bring an earthed neutral to the barn - PME-like.


They eventually conclude that once NE voltage is < 1V there is no issue, and up to 5V most animals are not affected.

slightly lower thresholds are suggested here

At the risk of stating the obvious, cow muck is likely to be reasonably conductive, not as good as salt water, but comparable to damp earth.

(and note that     manure has a high pH  here,   and  you can tell when soil was last manured by it's conductivity.)

Dry concrete is quite a good insulator at mains voltages, but as soon as it gets even slightly damp, less so.  If there was an external voltage gradient, from a buried faulty cable or fault running to a nearby earth terminal, then that voltage gradient could well appear in the building as well as outside. In some ways the slats make it more likely, as you can have one slat at a different potential to its neighbours.

However, gradients near electrodes tend to die out fast with distance - if you plant a vertical  electrode at 230V, and then stick your meter probes in nearby, such that you measure voltage to a fara way earth terminal, about half the voltage drop is within one electrode length of the top of the spike.

(If you wish to re-create this test, I strongly suggest not using full mains voltage, and not kneeling down to do the testing, and positioning the probes with it off, and then switching on from afar. )  My point is that within a few rod lengths away the surface voltage gradient has fallen to a safe level, so any such fault would have to be close.


Even though cattle have a long 'wheelbase' and are more sensitive to shock, they are not that sensitive, and the voltages likely to cause trouble are low but should be measurable on normal instruments.
Studies with current delivered from the mouth to hooves of dairy cattle in an environment which minimized contact resistance, indicated an avoidance reaction with currents of 1.0 to 4.0 ma AC. The same workers measured electrical resistance of dairy cows and determined an average value 390 ohms. Based on this work, it would appear that dairy cattle can "sense" currents of 1.0 to 6.0 ma AC and demonstrate a mild avoidance reaction at these levels. Using a 390 ohms resistance value, this translates to a threshold sensitivity of 0.4 to 2.4 volts.


from a Canadian paper   where common practice is to bring an earthed neutral to the barn - PME-like.


They eventually conclude that once NE voltage is < 1V there is no issue, and up to 5V most animals are not affected.

slightly lower thresholds are suggested here