Olsson’s Arginine Horse is a block supplement containing 4% arginine and 0.1% silymarin. Birdsville disease is a condition in horses associated with the ingestion of Indigofera linnaei, which may cause incoordination of gait and dragging of the hind limbs. Olsson’s Arginine Horse is intended for use as a nutritional supplement only and should not replace veterinary care. It may be used as part of a preventative management strategy, but veterinary advice is recommended if symptoms are present or if paddocks contain significant Indigofera linnaei growth.