I've had my grey squirrel for about 7 months now, I nursed him since he was a litle pinkie. He has always had some "kitten fur" on his sides but recently it seems to have gotten worse. I have bought and made him the recipe for hhb's but he refuses to eat them UNLESS I chop the blocks up into little bitty pieces, chop up pecans and then mix the whole thing with peanut butter. He gets plenty of fresh fruit and veggies dily too but my main concern is that 1) he seems a bit underweight 2) it seems like more fur is falling out. The weird thing is, the fur in his butt and back is thick (but not too shiny)....but its soo thin on the sides. He has been like this his entire life but lately it seems to be getting worse.
I'm not saying other issues might not be involved, but considering his age and the season and the pattern you described, this sounds like molt to me. When they don't have the environmental cues (temperature drop and photoperiod changes) their hair will molt but take a good while to grow back. They usually have a dark gray fuzz underneath that keeps them from appearing completely bald. The fact that where the hair is thick on his butt and back is not glossy suggests he may be lacking in some nutrients also.
I did some reading and I am going to buy him the vitamin drops and try to find this Kaytee forti diet.
If he's eating the HHBs (even with the peanut butter concoction) he should be getting the vitamins and minerals he needs. If you're going to try another block, however, I'd go with Harlan Teklad, available at thecraftyrat.com.
Previously he had been sick and I had to give him some baytril, the vet gave me this thing called critical care which I mix with water and the baytril. It turns into a mushy substance that I syringe fed, its sticky so he basically is forced to eat it since he can't spit it out. Should I add the vitamins from hhb to that formula and force feed it to him for now?
Critical Care is basically a formula. The vet was probably thinking that mixing the Baytril with the formula would make the Baytril easier to administer. I would NOT try mixing the vitamin mix with the formula because it would be so easy to overdo the amount.
I have bought calcium carbonate in the form of tums and rolaids but he doesn't eat them
You might try buying powdered calcium carbonate (squirrelsandmore.com) and sprinkling it on his food if you think he needs a calcium supplement. It would be best, however, if you gave him an assortment of veggies that are high in calcium in relation to phosphorus. Under the Nutrition Forum is a sticky called "Food Data Chart" that lists most fruits, veggies, and nuts and their calcium to phosphorus ratios. He's not going to absorb the calcium as he should, however, with out Vitamin D3, which is supplemented in rodent blocks but which is best (IMO) created naturally in his body by exposure to UV rays (sunlight or a UVB bulb).
Also, what can I do to increase fat? I give him avacados alot but he still doesn't seem to be plumping up.
Nuts and avacado are loaded with fat.
I thought about a release but he is incredibly friendly with everyone and everything right now (people and animals) and seems to be quite content living indoors. I do want him to have some natural sunlight though... has anyone tried leashes like the ferret ones?
Yes, again, he really needs to be exposed to UV rays (see above). If you're going to release him, you're going to need to "wild him up." If he has no fear of humans or other animals (eg dogs and cats), releasing him could be a death sentence. I have a neuro squirrel that doesn't mind a ferret harnass, but he's "special" and doesn't mind much of anything. I put it on one of my other non-releasables, however, and he was bucking bronco Buddy until I mananged to get the damned thing off--not without the loss of blood.
I am going to try to post some pictures but everytime I try the file is apparently too big, any suggestions?