I have hatched some game chickens in an incubator, and some are 7 weeks old, some are 11 weeks, 4 weeks, and 2 weeks. What kind of medicines do I give them. I have an 11 week old Kelso who Is week and skinny, but he's meen. I've only gave these chickens probiotics and v&e. How do I get my chickens healthy and strong. What am I doing wrong?