I'm a little worried about my chicks' weight. I can feel all of their breast bones but they have full access to food, water, and a chick stick. They also get meal worms every day because I'm trying to make them more friendly. No one seems to be acting sick. A couple have some loose stool but it doesn't smell and they don't have poopy butt. Is this something I need to be concerned about (also their brooder is very clean and very well ventilated. They have the ability to either lay right under the heat lamp or completely out of it depending on how they are feeling. I just don't know what I should be keeping an eye out for.