Not stupid, and yes, some don\'t seem to cycle very regularly, but most do.
It\'s not rare to take a race filly to the shed to be bred, then if pregnant continue to race her for a few months, or take her to the farm then.
Some trainers regularly use Regumate as a hormonal treatment in all their fillies to keep them from cycling in the spring and summer (altrenogest is a synthetic progestin).
That prevents the behavioral quirks that can occur with some in-season fillies or mares.
Some trainers don\'t ever use anything to adjust cycles. Some trainers only use Regumate if a filly\'s cycle behavioural changes interfer with her training.
Fillies and mares come into season in all horse sports - Olympic levels to backyard horses on a trail ride. It\'s just the deal with girls. Some mares are a behavioral pain during their cycle, some are not. Some seem to have ovarian pain when they ovulate, some do not.
I don\'t think it\'s a factor in betting.
As all these intact young colts can have sex and dominance on their minds, some more so than others. In some it\'s a problem, in some it\'s not.
