We have a small urban farm with about 40 silkies. All of them seem to be doing well with the exception of 2 hens and a rooster. They are all three young (about 6 months) and are getting skinnier by the day. When i pick them up and feel their gullets, it's like they haven't eaten anything all day! They are a bit timid, so i have been isolating them for 1/2 day to give them access to plenty of food, but that doesn't seem to be helping. Any ideas what's going on?