Of course, having seen that piece, I had to investigate further, and found lots more on the internet... here, here and here for starters. Then there are lots of archive photos... here, here and here with camels for a little variety here.
There's debate as to where Lizzy and her chums came from and where they moved on to after the war, although one theory suggests that the Sheffield Jungle came into the story at some point (and there are vast reams of university research on that topic.
And here's a cute little school animation project on Lizzie's story.
Other unusual animals were used around the same time to replace horses. Anyone care to exchange stories?