From Wikipedia:
Horsez is a video game released by Ubisoft on October 26, 2006, for the Nintendo DS, PlayStation 2, PC and Game Boy Advance. This PC game is the sequel to Champion Dreams: First to Ride and is also part of the second series of Petz. The user plays as Flora (the default name), a new member of the Sycamore Academy. Players select a horse from one of five breeds and a range of colours. The player trains their horse in different disciplines, enters shows, cares for the horse, and after a few weeks gains a foal to raise.
Horsez is also known as Pippa Funnell 3: The Golden Stirrup Challenge.