A jigger is a small electronic device that is held to a horse's neck to make it try harder or run faster.
Melbourne Cup-winning horse trainer Darren Weir is being investigated over allegations of animal cruelty after police seized four electric shock devices,known as"jiggers",during early morning twin raids on his stables.
Racing's dark underbelly is again in the spotlight,following the arrest of a prominent trainer. We take a look at the defining scandals in Australian racing history.
Darren Weir came from nowhere to dominate an industry where men of great means usually hold sway.
Police swooped on the stables in Miners Rest,near Ballarat,early on Wednesday morning,as well as his stables in Warrnambool.