I was looking for a copy of the humorous poem "The Flying Bum" in which is horse does get blown up by a bomb, but i couldn't find it. We're all ignoring Mat's theme of technology and inventions (including Mat) but I suppose you could say that the horse was technology for many centuries, revolutionising transport and agriculture and warfare. Very convenient for us, but it's easy to forget that the horse was originally wild and free until man came along to exploit it.
And in those days man seemed a harmless thing enough. No whisper of prophetic intelligence told the species of the terrible slavery that was to come, of the whip and spur and bearing-rein, the clumsy load and the slippery street, the insufficient food, and the knacker’s yard, that was to replace the wide grass-land and the freedom of the earth. (H.G.Wells "A Story of the Stone Age")