Dear Forum, Seventeen days ago we received 31 Cornish Roaster chicks from Murray McMurray. Nine are dead and two are in a separate brooder expected to die. Symptoms are very subtle and seem to simply be inactivity. Initially, chicks were not pooping much and McMurray suggested vegetable oil in the water, which seemed to work well. When one chick died in the first 48 hours, the vet suggested a chick booster from Tractor Supply for three days which we did. We also did the usual sugar in water the first 72 hours, not in combination with the chick booster. The chicks were brooded two weeks inside under a red light with clean equipment, frequent water changes and litter clean up. Temperature checked with thermometer. We gave oil in the water a few times when pooping seemed infrequent. Feeding organic chick starter, adding grit after three days and sprinkle in brewer's yeast for leg strength. All the same as last year's Murray McMurray group of 26, all of whom survived beautifully. Each morning we have a dead chick, not runts either but big healthy rooster chicks. I have a call into the vet and a few of my chicken-raising friends have been consulted and are baffled. The chicks were vaccinated against Marek and Coccidiosis, same as last year. They are given some greens and grass and there is no diarhhea problem. One pasty butt quickly solved. They have plenty of room in the outside coop, a red light, and shields against drafts from windows and doors. The problem is in identifying the sick ones. If it's a virus, I can't seem to remove the sick ones fast enough. Has anyone had a similar experience this spring? Thanks for your help.