Jim Byrne, Ryan Wiggins and apprentice Aidan Holt yesterday became the first jockeys to give blood as part of the Blood Donation Group initiative set up by the Queensland Jockeys Association.
Priscilla Schmidt has also pledged to join the group, while Byrne took his eldest son Corey to boost numbers.
Munce is being treated for throat cancer and is expected to be out of the saddle for up to six months.
Queensland Jockeys Association president Glen Prentice, who also donated blood, said members were desperate to help and this was a way of supporting Munce and other cancer sufferers.
Munce was moved by the initiative and said it showed another side to the often-maligned profession.
"It's a really touching gesture and it means a lot to me," he said.
"With my particular cancer it would be a worse case scenario needing a blood transfusion, but people who have other diseases like leukaemia and bone cancer, they need it all the time.
"You hear a lot of stories and innuendo about jockeys, but this goes to show what a solid group they are and hopefully it's something that will catch on."
Donors can lose up to 1kg when giving blood, but Wiggins said medics dashed any hopes they had of thinking it would be a new shortcut to beat the scales.
"Before we left they made sure we put just as much fluid back in as they took out," he said.
"We're all booked in to come back in three months and we will bring a few more next time we come.
"The boys had been talking for a while about what we could do and this seemed a good idea. Jim Byrne had given blood previously and a lot of the others were keen to join in too."
Prentice hopes 100 of the 225 registered jockeys in Queensland will joint the group. He said NSW and Victorian jockeys were keen to take on the challenge as well.
"A copy of the enrolment form will be sent to every jockey in Queensland and interstate riders will also be encouraged to set up their own Club Red account," Prentice said.
Munce remains upbeat about a positive outcome and said doctors were happy with the progress of his treatment.