Tainted hay causing skin disease in high-desert horses?

PHELAN, Calif. (KABC) -- Horse owners in the high desert fear a skin disease affecting horses is spreading. Worried horse owners want to know why some of their animals are getting sick.

Phelan resident Kendall Melline says it's hard to see her horses in this condition.

"Her eyes are swollen almost to being completely shut," said Melline.

It's called photodermatitis.

"She started to blister up and sunburn. She started looking a little lethargic," said Melline.

But she says one of the scariest things is that this doesn't appear to be an isolated case.

"I've heard about 70 other horses have come down with something like this," said Melline.

Stephanie Dorn says her horse is showing similar symptoms.

"She has mouth sores all over her whole entire muzzle, and her lips are just swollen humongous," said Dorn.

They've heard of horses showing similar symptoms in Norco. And a viewer sent Eyewitness News a picture from Agua Dulce.

"I've never seen anything like this," said Dorn.

So what's causing it? The thought among many: a bad batch of hay.

"Pull your hay, pull whatever you can, if you start noticing stuff like this," said Melline.

"Speaking with professionals, veterinarians and toxicologists up in UC Davis, it is a mystery," said Chuck Burt, Diamond B Hay and Feed.

Burt runs one of the feed stores that sold the hay in question. They've since pulled it from the shelves and are offering refunds.

UC Davis tested the hay and it came back clean. They say it's possible this was just an anomaly that was caused by the drought.

"It's the first time I've seen it. It's the first time a lot of people have seen it," said Burt.

Whatever the case, these horse owners are worried. And they hope to spread the word before more horses get sick.

"Just hopefully mine will live through it," said Dorn.