I have recently aquired a good 404sqm meter piece of land for my chickens as well as a substantial hutch capable of holding 40 chickens to a high standard. I was very excited about this so naturally I immediately went out and bought another 20 chickens bringing my flock up to 25 birds. Last year I bought 2 hylines from a local farmer who raises them to roam freely around his farm, as a result of this it took them a day or two to figure out where to lay eggs they were used to laying them in whatever nook and cranny they deemed appropriate! Anyway. They settled in just fine and I was pleased with thier eggs, size and temperment and so went back to the same farmer for my large 20 chicken order and got all hylines again. So my new 20 birds are all hylines and all just a month or so after POL. They are all laying, and the eggs they produce actually really shocked me! They are usually brown to dark brown, and around 70g to 90g for standard eggs. We are also getting an alarming amount of double yolkers (at least one a day) which weigh up to 110g. The hylines arent as big as my sussex - id class them more as medium fowl - so we were wondering already how they were managing to produce such awfully large eggs. Last week, my partner was shutting them in for the night and he noticed a flappy noise coming from the trees. Flapping in trees is not uncommon here as sometimes pheasants will come and roost there, but he had a look anyway and 'lo it was one of our hens out in the cold so to speak. She was on the ground and flapping about. He had no idea what was going on so he just picked her up and ran over to the house to get me. I looked her over and it became clear she had a prolapse and had been attacked by the girls as she was bleeding all down her bum. It was too late however, she died in his hands a few moment later before I could do anything. It's worth noting that 3 hours ago during my evening egg collection run, all the hens were completely fine and accounted for. We didn't get a double yolker for a few days, and thought perhaps she was the one laying them all the time and it was the cause of her death (or at least a symptom). Then less than a week later we got a double yolker again, and then again the next day - but we are unsure if this second one was a hyline egg or not as it lacked pigmentation and looked just like a sussex egg so we assumed it was a fluke from my sussex ranger. Then the next day, I myself go to the field to shut them in for the night and notice one hen is sat outside still. I go over and pick her up and she feels too limp and weak. I immediately check her over and see she has a prolapse but hasn't been attacked as far as I can tell. I take her to the house in order to try to reinsert the tissue, but she suddenly goes into death throws as soon as I step into the house. I have now had two chickens die from prolapse in the sapce of one week. Not only that but die suddenly from the prolapse - so quickly treatment cannot be offered and so quickly that the event cannot possibly have happened longer than 3 hours ago as we check them multiple times throughout the day. Medical Flock History and particulars * 1 light sussex 4-5 years old. laying but seems to be on her final year laying smaller less frequent eggs. (50-60g, in the past she laid up to 90g eggs at her peak at the end of the year). * 1 sussex ranger. laying well. average egg size 60-70g. * 1 unknown warren. Laying well, brooded last year. average egg size 60-70g. * 2 hylines, last years POL's. Laying well, average egg size 60-70g * 19 hylines (two deceased now as above details), this years POL. all seem to be laying as far as i can tell with number of eggs. egg size ranges from 70g to 90g with frequent double yolkers. * Weather has been abnormally sunny/hot the last week. hens have had access to shelter and plenty of water throughout. * Flock was treated for mites (on the chickens) 1 week ago and currently no mites can be found on them anymore. Hutches have been also diatomed just in case. nests are cleaned once every 3 days. * Diet consists of: layer pellers, mixed corn. grit, worms, leaves (reduced salads from the store, or what grows around here eg dandelion leaves or miners lettuce for example), sometimes on cold/rainy days they get a hot meal which includes oats, cider vinegar, fruit and veg. * They have one large feeder in the hutch overnight. I then also have a smaller feeder outside under cover in an unused hutch/run and a large treadle hopper (20kg) in the field. They have one large 30l drinker in the field, a small drinker in the unused hutch/run and then two large drinky cups connected to a 25l barrel on the outisde of the unused hutch/run. They are all filled by hose. SO. Is there anything I am doing that could be causing these prolapses? Or, is it just the breed is prone? Maybe they have a bad bloodline and I shouldn't get from this farmer again? Was it because of the stress of the mites earlier in the week making them prone? I'm stabbing the dark here so yeah, ideas appreciated. Thanks for your time!