Old MacDonald Duck is a Donald Duck short released 12 September 1941.
Summary[]
Farmer Donald sings "Old MacDonald" while feeding his animals. When he goes to milk Clementine the cow, she's not in the barn, she's perched up a tree, nibbling on leaves. She flutters down to be milked, and Donald begins. Her tail stops swinging to his song, so Donald leans over to check and it swats him in the face. He continues milking until a fly lands on his bill. Donald pulls his hat down over his face, but the fly crawls inside through a hole to bug him. Donald takes off his hat to shoo it, but in the confusion he gets his hat and pail confused. Donald starts squirting milk at the laughing fly, but the fly bites the cow's leg so she'll kick and send Donald flying.