Racing two-year-old horses should be stopped. They are the equivalent of teen-age humans. The growth plates at the ends of their bones are still highly active and their connective tissues have not reached full strength.
Many of the people in the Racing Industry are loudly bemoaning the looming ban of Lasix. Because of its effect of controlling the exercise induced pulmonary bleeding that is such a great problem now; they fear that many more horses will die or be disabled from racing. I will grant that in the short run, such will be the result of the ban.