This clip is catalogued as "116 Single Cow Moo" from the Hollywood Edge sound effects library. The existing page notes it was created by Disney sound legend Jimmy MacDonald for the Donald Duck cartoon Old MacDonald Duck, released on September 12, 1941. MacDonald was famous for voicing many Disney characters and crafting their signature sounds, and his cow moo became a go-to stock effect reused across animation and beyond. Today the moo lives on as a handy single-hit sound for creators who need an instant, no-setup farmyard cue.