Mature aged apprentice Jenny Duggan led a girls day out at Warwick Farm on Wednesday, celebrating her first metropolitan treble to boot.

With many of the leading riders in Melbourne for the spring carnival, it was the female apprentices who stepped up to the plate riding four of the seven winners.

Duggan headed the charge with an early running double aboard Laughing in the third race and favourite Medusa's Miss in the Co-Wynn Building Group Handicap (1400m).

She then had to wait for the final event to land her treble with a dashing all-the-way win on the Bjorn Baker-trained A Real Prince.

"I'm thrilled. I'm utterly excited," Duggan said.

"All the girls - there's more of us now. It's great. Watch out!"

A former amateur rider who was competing at picnic race meetings 12 months ago, Duggan started riding professionally earlier this year, shedding 10kg to join the professional ranks.

The switch netted her the 2011/12 Newcastle apprenticeship and the Bill Wade medal awarded by the club for her strike rate.

Duggan finished second at her only other ride at Warwick Farm when Miss Spoken was defeated a neck by Catkins, who was partnered by her female jockeys' room compatriot Alysha Collett.

Collett, who is on loan to premier trainer Chris Waller for three months, earned high praise from her temporary boss for her "perfect ride" on Catkins.

"It makes my job easier when they perform in a professional manner," Waller said.

"The winner was aided by a perfect ride by Alysha today. She can certainly sit on this girl."

Presiding steward Greg Rudolph said it was the first time he could recall female riders dominating a city card to such a degree.

"And in the second race, four out of the eight runners had girls on board and they finished first and second," Rudolph said.

"It goes to show there are some talented young female riders coming through the ranks."