'Pui' is used for both live animals and the meat. 'Pui' is also the translation for 'cub', for instance: 'pui de urs' - bear cub and so on. It could be any animal's infant even 'pui de om' - baby or child (human cub literally translated). If you want to talk specifically about chicks you could emphasis it this way: 'pui de gaina' - the offspring of a hen. 'Gaina' is reffered to an older female animal, I think 'hen' is the appropriate english word fot it.