Chick crumb is the first food baby chicks start on, and its much finer that other foods such as "grower" or "layer" which are sold in pellet form.
You can also get "mash" which is fed to battery farm hens, and rescued ex-batts when they first "come out". It is fine, like chick crumb.
P@h also now sell chicken stuff if you`re desperate, but the cheapest places will be countrywide, or other farm and equine surpliers. I pay about £7.25 at the mo for a 20kg sack of layer pellets.