I was going to say how the "Maestoso" from the Saint-Saens "Organ Symphony" was adapted effectively for those "Babe" movies, when I just now looked it up on Wikipedia and accidentally learned something new. (Unless, maybe, I already knew it once, and forgot it after my stroke of three years ago. It's possible. Constantly realizing things which I'd probably already known, at some point, is an embarrassing symptom of mine.)
In a memorable scene, the farmer character sings a song and dances a jig to cheer up the ailing pig before his big sheep-dog competition. I'd assumed (or had I?) that the lyrics to the tune were written for the film. It turns out, according to Wikipedia there was a 1977 pop hit called "If I Had Words," also based on the Saint-Saens tune.
I'd always thought maybe director Chris Noonan had intended to use Saint-Saens' other work "Carnival of the Animals," but found that the organ piece worked better for the film.