I left my guinea pigs outside for the day. I always check the weather and leave plenty of water and food also hay. I have this huge guinea pig run with hiding places and lots of shade. I left for a 6hr shift. Usually when I get back I check on them and their well being. Today I found 7 piggies dead and 1 still alive. They still had all their food and water. I need some idea what could have happened or what I did wrong. It was 72° today with a little wind. I never had problems with keeping them outside for a day. I always kept them clean and fed all the time as well as their oranges for vitamin c. I'm really sad what happened to them six were 1 year old or younger and the 7th was 3 years old.