I also save feathers from the birds I leave for necropsy. I personally save a few to frame with a photo, as I like to remember them. My vet does it (advanced avian necropsy) in house (she sends samples to labs for testing, which most state vets do anyhow) so I have the option for cremation, etc, should I wish. Last time I wrapped my hen up and brought her home to bury her; the knowledge that she is recycled back into the earth was more settling for me. We used to jokingly call her a 'mud chicken' because she was careless about getting filthy, so it seemed fitting. We miss her.