What’s On These Cows’ Heads? [VIDEO]

I was driving to see Dr. Kevin for my weekly adjustment when I noticed these cows in a field between Youngsville and Broussard.

I stopped to video them because a) they were wearing these funny-looking things on their heads and b) I didn't know what the funny-looking things on their heads were.

Can you help?  Is it something to protect them from the barbs on the fence?  Are they blinders of some sort?  Is it some sort of protection from being abducted by aliens?

Chime in if you know!  I am certain that there's a 4-H parent or member that can tell me!

(Via Youtube)