It would be difficult to find anyone who loves their horses more than Angela Welburn, who is struggling to save the life of one - and worrying about the others - at Integrity’s Haven Equine Rescue on Nova Scotia's South Shore.

“These guys are my children,” she said. “There isn't anything that's more important to me.”

One horse, Koko, is sick with botulism -- a rare form of poisoning that can kill. It started last week, when one of the other horses couldn't stand or eat. Then it happened to another.

And while she was at the vet with the second, Koko got sick too.

The first two horses - Freedom and Dakota - died within days.

“I'm broken, my heart is broken,” Welburn said.

The cause is something Welburn never even considered. Botulism is most commonly associated with wet feed, but she doesn't use that here, so she didn’t get the horses vaccinated.

Welburn says it was likely the dry hay.

“I freaked out because I’m killing my horses with food,” she said.

Botulism paralyzes the muscles. It means Koko can't swallow food or water, so Welburn has been practically living and sleeping in the barn.

She has spent many hours caring for Koko, going through IV bags full of electrolytes to keep Koko hydrated in the hopes that she will get better.

“She's very used to me doing all of this,” Welburn said.“It's just what I have to do, because if I went in and I went to sleep and came out and something happened to her, I wouldn't be able to … I’d be broken.”

Wednesday morning there was a moment of hope that only a horse lover could appreciate.

“She pooped!!” Welburn said. “It shows me that her intestinal muscles are still working and pushing it out.”

But with the good news, there was a little bad. Two of her other rescues - two zonkeys - are now showing symptoms too. And that’s not her only worry.

“I'm in debt past my eyeballs right now and I just need to save other horses,” Welburn said. “I have to be the educator here right now.”

Welburn wants horse owners to know that their horses can get botulism through dry hay, and that the solution is a vaccination that costs about $45 a horse. At this point, she has about $15,000 in veterinary bills.

With files from CTV Atlantic’s Heidi Petracek.