they're 4 wks old. my first ever. this afternoon when i let them outside for a few minutes i saw one with a bloody neck. then i saw it had blood on it's toenail. i washed the blood off & applied some medication (rooster something or other - i forget the name). do they get mites so quickly? or some other parasite? do i need to be giving them the opportunity to dust bathe & put some de in it? thanks for your input. btw... i think i need to get a diploma as i am officially now a chick vet.