Thanks, Also I think that the chicken got sick because of the hot weather we have here, is that possible?
I don't know where you are - your profile avatar doesn't say, but excessive heat can negatively affect chickens just like it does to humans. In extreme heat cases, we have brought birds in the house to cool down during the day if necessary. Fans in a run/coop help knock the heat down; so do misters, little wading pools, ice cubes in their water, and so on.
She doesn't seem to be getting the nutrients she needs, and that will make it harder for her to deal with excessive heat....