Found this cute story online in Serbian (here). Hence, the moral of the story was that the donkey is a Serb who goes without liturgy:
One day a donkey came home filled with joy, happy and proud. His mother asked him why is he so happy, what happened?!? “Mommy, they gave me to some Jesus, and when we entered Jerusalem, a multitude of people cried out: Hosanna, Hosanna, blessed is He who comes in the name of the Lord, glory to God in the heavens! They covered the road with their clothes and palm branches in front of me.”
His mother said: “Go back to that city, but this time alone.”
So, the next day the donkey went to the city alone and came back home very sad. “Mom, this can’t be! No one noticed me, and when they did they practically kicked me out!”
His mother looked at him and said: “Son, remember is, without Christ you are nothing but a donkey”.