The manure from any healthy animal, can be used to organically feed your plants. I personally would never use pig manure, because they carry a variety of parasites, that humans can contract easily. But that being said, deer manure would work. Just mix it 1 to 1, with some dry plant matter (grass, hay, or dandelions), let it work for two weeks, then topdress 2 ounces in a circle 8 inches out from your plants main stalk, if planted in the ground. If you're growing in pots, 1 tablespoon, every other week, during the veg period.
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One last note, most commercial animals are feed high ratios of corn to fatten them up. This corn feed is grown with basically NPK only ferts 99 % of the time, and is lacking in trace minerals. The manure from your free range deer, who graze on different grasses, berries, and plants, would contain a more complete mix of NPK & trace minerals, than commercial animals.
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If you really want a easy to gather, cheap source of ferts, get a pet rabbit, or find someone who has one. Most are fed alfalfa pellets, and timothy hay. Their manure, makes excellent fertilizer..... Rich in both NPK, superior to composted chicken manure, and with more trace minerals....
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Hope that helps.....
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