the answer is 24 to the best of my understanding. in a 2003 posting this article indicates 24 horses. there were 23 because a horse got a fever. I don't know if there has been a difference in competitors from 2003 to 2006. reference ===>> http://horseracing dot about dot com/od/melbournecup/l/aa110303a.htm
24 horses ran in the 2010 Melbourne Cup.
24 horses ran in the 2008 Melbourne Cup.
17
A limit of 24 horses can now run in the Melbourne Cup for safety reasons, though more than that have run in it in the past.
42
== ==
You can watch the horses run at Flemington.
3
Thoroughbred horses.
Normally about 24!!
shocking
So really silly people can place bets on horses