Dan Rosenberg, president of Robert Clay's Three Chimneys Farm near Midway, Ky., said the champion son of Elusive Quality only missed covering a few mares when it was discovered he had a plugged ampulla, blocking sperm from exiting his reproductive tract.
The 6-year-old stallion has resumed normal breeding activity.
"It basically is a sex gland that sits where the sperm are formed and empties into the urethra," Rosenberg said. "It is a condition I had heard of and read of, but in 35 years of managing stallions, this is the first time I had seen it."
Rosenberg said the condition was discovered during the viewing of a dismount sperm sample.
"When we breed, we always take a dismount sample," Rosenberg said. "Our stallion manager, Sandy Hatfield, noticed that there were no live sperm in the dismount sample. She immediately notified our veterinarian, Dr. (Jim) Morehead."
Dr. Morehead made the diagnosis after rectal palpation and an ultrasound.
Interestingly, Rosenberg said, the treatment for the condition calls for more frequent breeding and "we have done that. We have relieved the blockage."
He said at no time was Smarty Jones in discomfort.
"You have two testicles, two vas deferens, and two ampullae that drain into the urethra," Dr. Morehead said. "The opening from the ampullae to the urethra is small" and can become blocked.
Morehead said the condition is "not uncommon and well known to the veterinary community.
"Smarty Jones has been a good patient," he said.
"I want to stress that this is a transient problem," Rosenberg said. "He only missed a couple of mares. He will have no problem handling a full book of mares."
Rosenberg said Smarty Jones' syndicate agreement calls for him to cover 111 mares each year.
Smarty Jones won eight of nine lifetime starts including the 2004 Kentucky Derby (gr. I) and Preakness (gr. I). The horse, who raced for Roy and Pat Chapman, has stood all three years for $100,000.
In 2006, the first foals by Smarty Jones were offered at public auction. He had 13 offered and eight sold for an average of $275,626.