Parrot Finch with Bald Belly

[Egret]

Hi, All:
My Red-Throated Parrot Finch is causing me some concern. Several days ago I noticed his (don't really know the sex. Always call it a "him") shape looked odd, and he seemed a bit less hyperactive than usual. He is in a mixed flight, and he is on the move constantly (hence his name, PingPong), so it's just about impossible to get a photo of him.
Anyway, his outline just looked weird to me, so I sat down to watch him. In a while he stretched up tall on his legs, ducked his head down to his belly and seemed to be nibbling that area.
That's when I could see that he is now totally bald, from belly to vent. Basically everywhere underneath himself that he can reach.
I saw him scratch his head/neck a couple of times with his foot, which made me think of mites, but he has recently been through the 3-week S-76 protocol (in the water), during which time I observed him bathing in the open water cup with S-76 in it as well as drinking it from the tubes. So parasites seems unlikely to me.
I think it's possible he may have fatty liver disease. He eats constantly (always has since I've had him), and it's supposed to be a problem in these birds when they're not in a big flight to burn off all the food. I admit to indulging him a bit with extras such as eggfood and bugs a few times a week, because he loves them so. I've stopped that now. I can see the lower part of his belly is yellow, not reddish as the upper belly and chest is, which I believe is his fatty liver showing through.
Do any of you have any experience with this disease? From what I can gather, I'm going to need to catch him and give him his own flight, so he can get more exercise and so I can give him a low-fat, low-protein diet, with Milk Thistle added to the food and water.
I guess what I really am wondering is whether there is anything beyond what I've outlined here that a vet would have me do for him. Any prescription therapy or whatever.
There aren't many avian vets in the Nashville area, and I've been to 2 of the 3 I've found. Both were really dog/cat vets that were willing to "take a guess" at what to do with my birds. Neither vet had ever seen or heard of a grass parakeet, and the one I asked about finches said nobody brings finches to a vet, so he admits not knowing much about them. It was pretty much a joke, and a huge waste of time and money. There is practice in the area that purports to be a vet of "exotics" and birds, which I could try. The practice seems to be aimed more at the reptile and rodent crowd than avians, so I'm not overly hopeful. I hate taking birds, especially finches, to the vet without good cause, since the stress is sometimes harder on them than the ailment may be, but without knowing for sure what I'm dealing with, I can't really treat it myself, either!
Any thoughts?

[monotwine]

First off well done on looking up and covering all the basics. You seem to be answering all your questions.

Perhaps your PF is a bit fat and you have already answered your question by suggesting its own flight and a modified diet. You can also give it more free time out of its cage to do some exercise.

The lack of feathering could be from various things. Without knowing the extent of the balding it could be normal, excessive weight or plucking etc. having done mites and perhaps moving your bird to its own cage, the balding my rectify itself and you may never know its cause.
My hens are sometimes a bit bald below, but only when they sitting on eggs.

[Egret]

Dear monotwine:
Thanks for the input. I have decided that he is a She (not that it makes any difference), and her new flight is almost finished. I should have it done by the end of the week. She is quite social, so I will probably put a couple of other birds in with her, but it's twice the length of the one she's in now, and I'm going to leave the center area free of perches to encourage flight from end to end.
The good news is that she is already improving, having been on a diet for a little while. Her belly is going back to it's previous outline, and doesn't seem as yellowish. She doesn't nibble her belly anymore, either, or seem itchy.The other birds with her have not appreciated the leaner fare, but they have benefited from it. Her activity level has gone back up, as well.
The last time I kept birds I had large outdoor flights, and now I guess I will need to develop a different approach, since all my flights now are smaller, indoor ones, and some birds are just in large cages. I simply can't indulge them with as many rich treats as I did when I had them in room-sized outdoor flights!
Thanks again,

[monotwine]

Egret Glad to hear she is on the mend. You are a good finch mum. Tough love is sometimes the best medicine. Tougher on us not to indulge them than I think it is for the finches to go to leaner fare!