I had two Red Wattle females about two to three years old around 400 pounds. And had just purchased a white Kune Kune Boar to mate with them at around 200 pounds a month ago. I have a fenced in enclosure with a huge wallow and shelter that I keep them in for very wet, cold, or hot days. Otherwise I rotationally grazed them in pasture. Switched over to making my own feed 8 months ago, no mold or anything that I saw. I decided to move them to pasture Saturday afternoon. Fed them Saturday night, Sunday early morning, and then again on Sunday at 11ish and gave them fresh water. Filled thier container slightly under half which is the size of a small bathtub bc they slosh it out to that point most days anyway. At 11am they seemed great. They ran to the food like they normally do. Ate all of it no problem. They were not panting or moving slowly. They seemed perfectly healthy and comfortable. The high that day was 90 degrees. It was close to that when I saw them at 11am. I come back around 8am the next morning and they are all laying on the ground dead with flys and blood coming out of thier noses and mouths and thier anus extruding out. The water was completely gone. I feel terrible! I failed them. Any help or advice on what could have gone wrong would be super appreciated. I want to know what I can do to make sure this never happens again. I was thinking maybe heat stroke. One female was in heat. They didn't have much shade or a wallow. But there was a small tree with some shade which they were no where near. And they seemed perfectly okay at 11am, not hot at all or I would've given them some extra water to make a wallow with. They've survived much hotter summers on the pasture as well which is why I didn't think the low humidity 90s was going to bother them. Also I find it weird that all three of them died at the same time. Another theory is that they maybe ate a noxious weed in the pasture like nightshade. Or maybe got a bacteria or something that caused sudden death. Every vet couldn't come to do an autopsy until later in the week and they were starting to decompose so I had to bury them. Please let me know if you have any experience or expertise in this.