Here is some info that I have found important for squirrel care.
If your pet squirrel has hair loss and is itchy.
Please consider oxalate crystals.
Cherry juice will remove oxalate crystals, given in small amounts (a couple drops each hour) because as the crystals are disolved their elimination will put a huge burden on the kidneys.
If your squirrel continues with high consentrations of oxalate crystals, they will have terminal metabolic bone disease and die.
Oxalate cyrstals are formed by feeding them too many foods high in oxalate, and oxalates BLOCK calcium absorption. Stop feeding them corn also as that is high in phosphates and will also block calcium absorption.
More info is being developed.