I have an approximately 8 week old duckling that I tried to integrate into the flock and I went out and baby could not walk. I did this at the same time I integrated 3 other ducklings the same age. So I separated this duckling and now she is only getting around by pulling herself with her head and stabilizing herself with one wing. she has not gotten up and walked. now I see that the webbing in her feet is black. Is it time to Euthanize? she is still eating and drinking. This happened about 2 weeks ago. Any advice is welcome!