By Alan Gionet

CAÑON CITY, Colo. (CBS4) – The Bureau of Land Management has a team of people looking for answers as to why dozens of horses have died in captivity at the Cañon City Wild Horse and Burro Facility. That facility is now under quarantine.

At latest count Tuesday, 67 horses had died since the start of the weekend from a mysterious illness causing apparent respiratory and neurological effects.

“More horses could die,” said BLM Colorado Communications Director Steven Hall.

(credit: CBS)

An independent and a federal veterinarian are on-site as well as academic experts are looking for a cause.

“We’ve got necropsies being performed on them, some of the horses blood samples tissue samples, and we really hope to have an answer that we can share with the public and help us get ahead of this as soon as we as soon as possible,” said Hall.

More than 2,500 horses are currently kept at the facility. The illness became apparent late last week among horses mostly gathered from the West Douglas area west of Meeker in Western Colorado. In addition, some of the ill horses were gathered in the Sand Wash Basin to the north in northwest Colorado.

The Wet Mountains overlook the pens of the East Cañon City Prison Complex. (credit: Mark Neitro, CBS4)

They have been at the facility since late last summer. The horses from the West Douglas area says Hall, were not in great shape when they came in.

“It’s hard to make any blanket statement about all the horses, but… that that is really a tough area for wild horses to exist and remain healthy.”

They don’t know how the disease may have gotten into the herd, but as they separate sick animals, they are trying to isolate exposure.

David Jackson and Alex Cockrell walk through a pen holding wild horses from the Sand Wash Basin while on their shift working at the state prison in Cañon City. (credit: Mark Neitro, CBS4)

“We’re not sure how effective that will be over the long haul, and we started a voluntary quarantine of the entire facility to do whatever we could to keep this from spreading beyond the Cañon City facility.”

The horses are having trouble breathing when the onset is noticed.

“There seems to be a respiratory component and also a neurological component,” said Hall. “So the trouble with breathing seems to be one of the initial symptoms that we observe and some of the relatively quick onset and then death of these horses seems to be tied in with their nervous system.”

The gathering of wild horses has long been a controversial practice. At the facility, they are cared for and hopefully prepared for eventual adoption.

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They are penned and the concentration of the horses can increase the chances of spreading disease.

“It’s certainly safe to say that when you congregate horses, just like people, there’s greater chances of infection spreading in those congregated groups. So that’s absolutely the case,” said Hall.

“We certainly hope Congress takes note. We want to see an investigation immediately into the conditions,” said Scott Wilson of the animal advocacy group, The American Wild Horse Campaign. “The bigger picture is if we didn’t have roundups, we would have confinement and we wouldn’t have this contagion.”

The BLM notes the illness is upsetting to staffers as well.

“I know we have these experts in their field engaged doing everything they can scientifically to get at what is causing the sickness among these horses,” said Hall.

Alan Gionet