January 31, 2007
Barbaro’s Death Brings Focus to Laminitis Disease in Horses
WASHINGTON -- The death of Kentucky Derby winner Barbaro shines a spotlight on a little-understood health problem that every year kills thousands of horses.
Despite decades of research into the causes of laminitis, the disease can't be prevented and can't be cured. Scientists disagree about the causes, and vets have competing theories on treatment. Horses of all breeds and ages are susceptible, and when they get it, all that vets can do is treat it and hope it gets better.Barbaro proves that even the best, most expensive care in the world may be futile if the case is bad enough.
In many respects, Barbaro was lucky. After surgery to repair the right hind leg that was shattered in the Preakness, Barbaro was monitored around the clock. His vet, Dr. Dean Richardson, said from the beginning that the broken leg would predispose Barbaro to laminitis. So he took steps to stave it off, fitting Barbaro with a special shoe and using a sling he could rest in.
When the left hind leg suddenly developed severe laminitis in July, Richardson removed 80 percent of the hoof in an attempt to regrow the damaged tissue. He tried different shoes, casts, braces _ everything known to veterinary medicine. But nothing stopped it from spreading. Rather than dooming Barbaro to a lifetime in pain, owners Roy and Gretchen Jackson chose to euthanize him.
It's a sad route familiar to all vets and many horse owners.
"Everyone shares in this. Barbaro and your neighbor's little girl's pony have the same problem," said Ed Bowen, president of the Grayson-Jockey Club Research Foundation in Lexington, the day after Barbaro's death. Laminitis is "fierce" and "insidious," he said, and since the late 1980s the foundation has put $1.2 million into laminitis-related research.
Despite being a top equine research priority around the globe, laminitis remains the second biggest killer of horses, behind colic.
A 2000, U.S. Department of Agriculture study found that 13 percent of more than a thousand horse establishments, excluding racetracks, had at least one case of laminitis the previous year, and that almost 5 percent of those horses died or were euthanized. Boarding and training facilities and breeding farms were more likely to have had a case than other places. This study found that three-quarters of all horses afflicted recovered, but other studies have shown that in severe cases as many as half the horses died or were euthanized.
Laminitis is a painful separation of the hoof wall from the foot bone inside it. The laminae are tiny connective tissues. When laminitis occurs, most often in the front feet, the layers split like wet corrugated cardboard. If the process can't be stopped, eventually the bone will push through the bottom of the foot.
Vets and horse owners have long associated laminitis with horses that don't stand on all four feet evenly and have long known it can be connected to overeating. In 350 B.C. Aristotle described it, calling it "barley disease."
But there are different kinds of laminitis, some related to rich pasture, others to pressure. And there are conflicting theories about almost every aspect, from the triggers to the treatments.
For instance, it has been widely accepted that part of the problem was a loss of blood flow, but researchers in Australia have concluded that limiting blood flow through cryotherapy can slow the disease's progression. Other prominent researchers in the United States disagree entirely.
Such differences leave vets in the field nowhere, said Dr. Doug Byars, a critical care vet in Lexington. He said current treatments haven't advanced much with knowledge of the disease.
"We know a tremendous amount of the physiology, but as to what we do for the animal, it's not much different from dragging them behind a cavalry wagon 200 years ago or dragging them into a stream," Byars said.
And often by the time vets know a horse has been hit, it may be too late for any present treatment to have much mitigating effect. By the time a horse is in pain, laminitis often has been developing for days.
Australian researcher Dr. Christopher Pollitt wrote, "Severe damage to the internal anatomy of the hoof can occur within the space of a few hours and the severity and extent of this initial damage is the single most important factor influencing the final outcome."
Pollitt heads the Australian Equine Laminitis Research Unit at the University of Queensland, which has invested more than $2 million in the last eight years into studying the disease, according to the school's Web site. In 2004, Pollitt and 40 other scientists met in Louisville to share what they know on laminitis. Among their published conclusions: that research is "woefully underfunded."
Ohio State University professor Dr. Rustin Moore reiterated that in a statement on Barbaro for the American Association of Equine Practitioners.
"Despite the marvelous veterinary progress made in equine surgery, anesthesia, and the design and development of state-of-the-art implants for fracture repair, the ultimate outcome for horses with life-threatening injuries often depends on effectively treating, and ideally preventing, laminitis," Moore wrote.
He noted that an estimated 15 percent of all horses experience laminitis at some point, and that as much as 75 percent of the afflicted eventually develop severe or chronic lameness or debilitation.
Moore, who is also a top researcher into the disease, estimated it would take a working research budget of $10 million to make substantial progress in the next five years.
Such money has historically come largely from private, charitable organizations. Already there is more than one fund in his name.
"Although it was a terrible tragedy with Barbaro, there were a lot of positive things," said Dr. Celeste Kunz, a New Jersey vet who studied under Barbaro's vet. Barbaro has "done so much for us as a community and as veterinarians. One of his gifts is an outpouring of people interested and caring, and this is one way we can help."
But, as Barbaro also showed, money is not enough. Finding ways to prevent and cure laminitis will take time and cooperation and work.
"If we knew it was going to cost us a $100 million, we would raise it in a day," Kunz said Tuesday. "It's not a question of that _ it's continuing to put more resources into it."