Till The Cows Come Home

I'm not sure if anyone has seen this amazing video that is getting a lot of hits on YouTube. It's basically a man playing the trombone in a lawn chair outside. But the song is very important because for some reason his cattle love it. The man starts playing "Royals" by Lorde. Minutes later his cows come running from all over to him with their tails wagging. It's the most amazing thing I've seen. I know that some dogs sing to certain songs but cows reacting to a trombone song blows my mind. And I did have one question, how many songs did it take for the man to find out they liked "Royals"?

Well, if you haven't seen it here you go.

https://www.youtube.com/watch?v=qs_-emj1qR4