This right here. Go to a farmers market maybe and talk to some people about getting some manure. Cow manure, if dry, is not smelly and plants love it. I'm guessing it's because cows are mostly vegetarian. Chicken poop smells, but chickens will eat animals. Pig shit stinks to high heaven and we all know they will kill and eat humans. I don't have much experience with horse manure, but to me it smells a bit more than cow but less than the others I mentioned.