C-72.1, r. 4 - Rules respecting Standardbred horse races held at a professional race track

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340. An official sample:
(1)  shall be taken from:
(a)  the winning horse in a race with pari-mutuel betting;
(b)  a horse participating in a time trial race;
(2)  may be taken, where a racing judge so requests, from a horse declared in a race:
(a)  after it has participated in the race;
(b)  within 2 hours before the starting time of the race in which it is to participate.
Decision 90-09-19, s. 340.