You can suppress estrus in mares - I would guess her estrus is already suppressed.
First race off a layoff. Big deal. It was a good effort for a training race, she had to put out but Borel didn\'t punish her (a good thing).
It means nothing for the rest of the year. She could come back and be HOY this year, too. She looked unmuscled and only about 80% in the paddock to me to me. Just like one would expect a horse to look ... first off a layoff.
Horses are not 100% every race. You get the horse fit, then pick the race when they are ready. Aiming for a certain race (take the Derby every year as an example) - nonsensically difficult. Horses aren\'t robots. You can try to train them up to a target race, but it doesn\'t mean the horse will cooperate.
Edit: in the rest of the world, good horses are not expected to win their prep-races leading up to the big race. Nobody freaks over it. In fact, a good but unplaced showing could be the perfect prep to destroying the competition next time out. Geesh, folks - these were only prep races. Public works. It\'s the body of work over the season that will count (remember \"seasons\"? Where horses were not expected to do the impossible and race year-round, but had some months off, and were brought back fat and hairy?)