C-72.1, r. 5 - Rules respecting Standardbred horse races held at an amateur race track

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253. An official sample may be taken, where the racing judge so requests, from a horse declared in a race:
(1)  after it has participated in the race;
(2)  within 2 hours before the starting time of the race in which it is to participate.
Decision 96-07-24, s. 253.