The state is planning to euthanize the remaining bighorn sheep on Antelope Island after an outbreak of an extremely contagious respiratory disease reduced the population from 150 to 26, FOX 13 reports.

“Much like pneumonia, it has gotten into this herd and these pathogens get into these wild sheep herds and they pass quickly from animal to animal,” Division of Wildlife Resources spokesman Mark Hadley told FOX 13. “It ends up being a very slow and very agonizing death. It’s painful to watch.”

State crews will search the island for the remaining sheep and euthanize them to prevent more suffering.

See more at FOX 13.

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