About 20 years ago on TV I remember seeing a short animation, which I think was by Disney, of an old barn and its inhabitants. I can't find any mention of it on imdb. It might not be Disney, and it might not be called The Old Barn - but it certainly looked like it was made in the '40s. If anyone could supply the title, or details about it on another site, I'd be very grateful.
But your answer did help me as I looked up 'The Old Farm' on Google and, by some stroke of luck, I got a link to the film I was looking for which was actually called The Old Mill.