These are the first tracks in North America to ban the use of Lasix, a substance not allowed by nearly every other country, the Los Angeles Times reported.
Lasix is a diuretic given to horses hours before a race, causing them to urinate nearly 5 gallons before competing. Nineteen of the 22 horses killed had Lasix in their system, the Times reported. Records for the other three horses were not available.
The Stronach Group is also expanding bans on painkillers, anabolic steroids and shockwave therapy.