She looks lethargic and seems to have something neurological going on. Was she vaccinated for Mareks disease? I am surprised that your vet could not have you hold her while he looked into her throat with a light. You could get a feeding tube and large syringe from your vet, and start tube feeding her for some time to give her nourishment, until she is either better, or you decide to put her down.
Google “Go team tube feeding” a good thread by Casportpony with videos on learning to tube feed. It is fairly easy to do once you learn. KayTee baby bird feed is good to use for feeding. For just fluids, I have used aquarium air tubing and a regular 35 ml syringe placed into the crop.
Google “Go team tube feeding” a good thread by Casportpony with videos on learning to tube feed. It is fairly easy to do once you learn. KayTee baby bird feed is good to use for feeding. For just fluids, I have used aquarium air tubing and a regular 35 ml syringe placed into the crop.