UFO scares cows and starts stampede breaking electric fence

My friend and I were returning home one evening, after fishing about 7-8pm.  It was clear with no wind or noises.  We were taking the back roads home in the country.  As I was driving my friend said look at that.  We both saw this object very slowly descending down.  It looked like something close to being spherical shape with white lights revolving around it.  We were about 1/4 mile away.  There was absolutely no noise which was extremely odd. 
I turned down the next country and watched this object slowly go down behind a house with hills behind it.  As we got to the house where this went down, there were cows running all over the road, frightened and mooing.  They had broke through an electric fence that was popping on the ground.  
We stopped to try and get the cows off the road, when a neighbor, whom I knew, came down to help.  He asked if we knew what had happened because cows just don't break down an electric fence for nothing.  We didn't say anything about what we had just seen. No one was home at the house when this happened.  I've often thought about going back there but that was 40 years ago.  My friend and I still talk about it.  It was real.  I still wonder what it was to this day.
Witness indicates that the date of the sighting is approximate.  PD