Who lost the derby?

Seven horses in a farm in Kentucky,
Of three blacks, the oldest is a daddy;
Of two browns, the 3 year old male is called BILLY,
And the horse SNOWY is white as a lily.

Of two half-sister mares, the black won in the Derby,
She's a shade lighter than her daughter, BEAUTY;
BEAUTY and her cousin LUCKY, both half the age of their auntie,
But faster than either ROCKY or SUNNY.

Three of the horses are ready for the Derby,
A horse must be three years to be an entry;
Maybe this year the farm gets lucky,
Their stallion's loss last year was a pity.


CHALLENGE: Describe the horse that lost in last year's Derby.


Andrew

The horse has four legs and is hairy