I am going to say copper also, I have a doe that does this every year when she kids, goes bald, dry rough skin.. I copper bolus her and two weeks to one month later she is the beautiful red she is suppose to be.. and she is a very nice doe..
Isn't Red Cell an iron based product? Everyone is off of feed here due to the furnace we live in. The hair loss.. have you checked (I mean really checked) for mites? I would bathe her in a baby shampoo with some apple cider vinegar thrown in.. will help get rid of mites and add some condition to her coat..
Sorry, but that's about all I can think of. :?
Zinc and vit A is also what I was thinking. If you have been giving red cell for all this time you could be running into the other extreme of giving too much iron. Iron is not something that most goats need to have as a supplement as all the iron they need is present in the soils and food they already have. Excess iron depresses immune function and inhibits the absorption of other minerals zinc included. If given enough copper they will absorb enough iron from their food and supplements.
She is 13.
I told the vet about her hair and he did not agree that it was a deficency as he said he had seen my herd recently and they are all healthy and shiney and he can't see how just one goat would be having these deficencys.
I love him to peaces but we do not always agree and I don't agree with him this time.
He thinks she is just shutting down and I will agree that is likely because it happened so quickly but I also think that at her age she is not able to absorb vitamins and minerals like the younger goats.
The fact that I do not see her drink water and she waddles from being bloated lets me know she is shutting down but I want to do all I can for her anyway.
I put her in with the donkey and alpacas today.
She and the donkey are Sisters and I know she wants to spend her last days with her and not be pushed around by the other goats.