Poultry Nutrition Earthworm Liquid Promin  is an advange for agriculture in Vietnam. Why Earthworm Liquid Promin Earthworms - An animal feed alternative It is common for free-range chickens to consume earthworms. Earthworms are very efficient at converting plant and animal wastes into biomass that can be used as a feed ingredient in animal production: a ton of animal wastes will produce about 100 kg of worms (Edwards, 1985). Earthworms are a good quality protein for use in animal feeds, but the practical use of earthworm meal is influenced by economics. Technology is available