Originally Posted by Vegman
So should I use some animal byproducts but not others? were do I draw the line? How far is too far and how far is not far enough?
These are all good questions that you should think seriously about. No one here can make these decisions for you. The best thing you can do is educate yourself about where your various animal products are coming from, how they might impact the animals, and if there are suitable alternatives.
Manure I see almost no issues with as it is something that needs to be removed anyway. Honey is no big deal for me as I don't see insects as sentient beings. Roadkill..well, that's already dead, so no harm done there. I wouldn't consider it "vegan," but it seems perfectly ethical to me to use the body of an animal that is already dead due to an accident.
Blood and bone that came from livestock killed for profit seems fundamentally different. Are you paying for it, or is it something that would be thrown away? If you're paying for it, you are in a small way making the slaughter of those animals more profitable. But, if it's something that is very necessary for your gardening and there are absolutely no alternatives, I could see using it. I would do some more homework though and find out what your alternatives might be.