chicks are 8-10 wks old, just switched over to 20% non medicated starter. They were on Purina medicated chick starter, and have only been on the new feed for 4 days. Already lost afew chicks, just found blood in the pine shavings today, and upon checking for injuries, found bloody vents (on feathers) and a chick actually discharged blood in front of me. I cant say it is bloody poo...because no stool appeared in the blood at all. Makes no sense to me! I brought in the lethargic chicks, and most are eating/drinking...feel very underweight though and bony. These are cochins, and the ones i lost were welsummer and afew cochins today. I just lost the welsummer cockerals yesterday. Tonight i lost another cochin!!! Any ideas??? I am at a loss...dont know what is going on, but i wonder about the feed change and i got another bag of Purina chick starter tonight.