Veterinarians think they may have an idea of what killed 25 foals in California.
According to Jeff Fontana, spokesman for the Bureau of Land Management corrals in Litchfield, the foals were from mares gathered from the Devil's Garden Wild Horse Territory on the Modoc National Forest in September 2016.
Of the 221 horses gathered in the roundup, more than 100 were adopted, while about 50 mares were given a birth control drug and returned to the herd's territory.
BLM wranglers noticed flu-like symptoms in some of the remaining horses earlier this month, all of which were being kept in a single pen. Though veterinarians treated the horses' symptoms, Fontana said the condition of the foals continued to worsen.
25 of the horses in the affected pen died from the illness, which luckily doesn't seem to have spread to the other 300 mustangs at the facility.
BLM officials hired an independent veterinarian to investigate the deaths. They have taken blood and tissue samples and expect to receive results, which may point to colitis, within a few days.
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