Bless you for saving Mow! You are AWESOME!
It is possible she has earmites. Those cannot be seen with the naked eye.
Use revolution monthly on her neck. It will kill fleas, ticks, earmites, worms and affords some heartworm protection.
She does need to see a vet since she was outdoors. She may just be malnourished but should pick up now that she has YOU to feed her properly.
Cats are not big water drinkers so don't worry if you do not see her drinking. She will get enough fluids if she eats canned food because it is 60% water.
You can drain the water from a can of tuna and let her lap it up every other day.
Please let me know how she is doing. REply here or if you prefer we can speak on the phone.
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