A follow-up look at some of the racing statistics of juveniles involved in the furosemide observational study results released Dec. 16 by Breeders’ Cup from this year’s World Championships and two California-bred stakes races for 2-year-olds at Santa Anita Park provides some interesting additional information.

The observational study found that 2-year-olds racing without race-day furosemide (commonly called Lasix or Salix) at the 2013 Breeders’ Cup—the four World Championship races plus the Juvenile Turf Sprint—had fewer and less severe instances of exercise-induced pulmonary hemorrhage than juveniles who raced with the diuretic that same weekend at Santa Anita in a pair of stakes for California-breds.

In the voluntary study that saw connections of 70.5% of the horses participate, 71% of the horses who raced with Salix (10 of 14) were observed to have some level of EIPH while just 37% of the non-treated horses (15 of 41) showed some level of EIPH.

The severity of EIPH was determined on a four-grade (four being most severe) scale. The Salix-treated horses again showed significantly higher numbers of severe bleeding, as 36% (five of 14) showed grade three or grade four EIPH, compared with only 7% (three of 41) at those grade levels in the non-treated group