A 13-year-old thoroughbred gelding named Rainaway, the champion's great-grandson, was among the sickest horses found last week at a stable in Sullivan County.
His lineage was confirmed by an identifying tattoo on the inside of his lip, according to Sullivan County Assistant District Attorney Teresa Murray Smith.
Karen Harlan, 47, appeared in court on Tuesday on 15 counts of cruelty to animals and one worthless check charge. Her attorney, Andrew Gibbons, said she wants to go to trial.
According to investigators, the horses had little food and water for months. Rainaway, who bears a white star on his forehead, was scarred and extremely thin.
The horses are now being treated at Horse Haven of Tennessee, a Knoxville-based organization that cares for abused and neglected horses.
"They're all holding their own. We're keeping our fingers crossed," said Nina Margetson, executive director.
Secretariat, one of only 11 horses to win the Kentucky Derby, the Preakness Stakes and the Belmont Stakes, is considered to be the one of the greatest race horses ever.
It was not immediately clear how Harlan came to own Rainaway.
According to The Jockey Club, the breed registry for all thoroughbreds in North America, Rainaway was born in April 1994 to Summer Squall and Ms. Eloise and began racing in 1997 at age 3 at Thistledown near Cleveland. He retired at the age of 6 in 2000.
He had 31 starts, five first-place wins, six second-place finishes and five third-place finishes with a total of $90,933 in lifetime winnings.
Harlan is scheduled to appear again in court on July 31. If convicted, she faces up to one year in jail on each cruelty charge.