I read online and it says good for ALL birds. It's basically vitamins. I figure if it's not too potent for my parakeets it won't be too potent for my chicks. I bought it at PetSmart.
Edited by Bridebeliever - 9/19/15 at 8:37pm
The itty bitty one could be a bantam - did it hatch later than the others? Usually chicken folks get Polyvisol infant drops (NO iron) - Walmart and drug stores etc. carry that for babies. Give 2 drops, 3 times a day. I recommend putting it just inside the beak- so the chick can push it back out if he doesn't want it. Better than having it choke him
The chick may be getting pushed away from the feed and water by the bigger ones. That would be a plausible explanation why it is small and shakier. The bigger ones may be knocking it over or walking on him - which can set him back also.
I think he should be in a small cage by himself where he has water and feed and can eat as much as he wants You can give him a small stuffed toy to cuddle with and a mirror, so he thinks there is another chick with him. Maybe he is cold and needs a heat lamp - smaller chicks usually do. You haven't mentioned a brooder, so I am guessing you are living in a warm-or hot climate and don't feel baby chicks need it.
You could also supplement him with some finely mashed hard boiled egg yolk moistened a bit so it's easier to eat. Chicks usually love that.