I have 1 week old chicks. This was my first batch ordering from McMuarry hatchery. We've always ordered from our local poultry processing or feed store. The feed store closed and processing isn't open till april. Anyways we always get Cornish x but McMuarry offers these jumbo Cornish x. I don't know if that's the difference but i've lost 8 of the chicks. I am unsure if that's the problem at one week they seem to already be having leg problems. They stop using the one leg and can only hobble around then they get walked on and die. I removed 2 of them and placed them in the brooder with my partridge chochin chicks. I would say they are about half the size of the other broilers chicks and they barely move. I go out every hour or two so help them get to the water and they drink like crazy when I put them over there. I would think maybe their legs were broken but the broilers in the big brooder have plenty of room and they aren't crowding together for heat. Any ideas? Also they are not vaccinated for marek's. They are getting Broiler booster.