In this video, Derek calls his heifers from out in the pasture with his trombone! For the past week, they had been feeding the heifers treats when they came, and for fun he had added the sound of his trombone. Now they come running when they hear the sound of his music!
Their parody (a parody means writing new words to a well-known song) of "What Does the Fox Say" was also a big hit. Here is "What Does the Farmer Say?"