KAILUA-KONA — Hawaii investigators are closing in on the cause of a mysterious disease linked to the deaths of about a dozen wild horses over past two months on the Big Island.
The state Department of Agriculture is receiving results from lab tests, helping investigators grasp a clearer picture of the symptoms and rule out various ailments, West Hawaii Today reported Wednesday.
About 15 wild horses in Waipio Valley have been afflicted with the unidentified disorder that causes nerve damage, according to the department. The symptoms first appear in the horse’s hind limbs, altering the animal’s gait. It eventually makes the animal unable to move, resulting in their deaths.
Two of the 15 horse are believed to be still alive and roaming the valley, said Jason Moniz, program manager of the department’s Animal Disease Control Branch. The third horse was dying and euthanized.
“No new mortalities have been seen in the area,” Moniz said in a statement. “Farmers in the area have observed a handful (4-5) of new wild horses from an adjacent band hanging out in the area now. Farmers are assisting with monitoring and observations and will report new cases.”
Several tests are still pending, but the investigators have ruled out several possible causes. Several residents have floated the possibility of rat lungworm disease, but the tests have found a “very low quantity” of related DNA, Moniz said.
“Correlation with histopathological findings are not present at this point,” Moniz said. “Further histopathological exams will be completed before a final diagnosis will be made.”
Labs have detected sarcocystosis, which can cause conditions that involve weight loss and muscle loss in horses. It can cause equine protozoal meyloencephalitis, but tests have ruled out that specific disease.
“There are other species of Sarcocystis however, one in particular, Sarcocystis fayeri can cause illness similar to what has been seen in the Waipio horses,” Moniz said. “Further evaluation of tissues will be conducted and additional test(s) will be sought out to rule this in or out as a cause of the illness.”
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Information from: West Hawaii Today, http://www.westhawaiitoday.com
