I saw a tutorial somewhere recently about gathering your own down and making a sleeping bag or quilt out of it, havent been able to remember exactly where I saw it but will post the link if I do.
From what I remember though, he put the down into the freezer to kill any lice, etc, that may have been living in the down before he used it. That is the only processing he mentioned.
Hope this is of some help, but I wouldnt place too much trust in my second hand knowledge! I will try find the link.