I had 4 flemish giant rabbits. They're a couple years old, fat and healthy. They live outside in Arizona. It has gotten cooler but there's a heat lamp out there. They live with 11 hens and 4 guinea pigs. I went out there last week and my new guinea pig, a Cuy was dead. My male flemish was on his side and struggling to breath. There were no signs of trauma. I put him in a cage, normally he runs free. I gave him salad but I knew he was gonna be dead soon and he died within the hour. Today I went outside and my female had the exact same symptoms. She was in perfect health before this. We picked her up and put her in a cage and she died in minutes. Whatever is killing them is doing it fast. What could it be? Are my other rabbits likely infected too?