Vermiculture (from Latin word vermis, meaning worm) is the intentional rearing of earthworms to produce more earthworms. It involves the mass production of certain species of this annelid worm by providing them appropriate food and optimum conditions for their growth and reproduction.
The initial product of vermi culture is live earthworm in sufficient quantity. It is utilized for various purposes such as for fish bait, vermimeal, vermiceuticals, and other uses of earthworm whether live or processed (click to read uses of earthworms).
Earthworm production has also become a promising alternative for income generation due to strong demand for live worms in composting. As a necessary consequence of the culture system, a secondary product, called vermicompost, is produced from the food provided to the earthworms.
Vermiculture and vermicomposting are therefore inseparable. Vermiculture requires the use of organic materials as feed of the earthworms. To accelerate the production of earthworms, it is necessary to understand not only the breeding and growth requirements of the organism but also the process of producing compost. Conversely, the process of vermicomposting requires also an understanding of earthworms, particularly those which are efficient decomposers. In either system, both earthworms and vermicomposts are produced.
What is good for one is good for the other. By providing the right organic materials or combination plus optimum environmental conditions to the worms, they will eat, grow and breed faster. At the same time, the given feed will be rapidly converted into compost. However, this has certain limitations. Guerrero et al. (1984) reported that the nutrient content of vermicompost produced from pig manure – sawdust mixture decreased with increase in earthworm production. This is attributed to the bioconversion of the nutrients into earthworm flesh.
Conversely, it was observed that a delay in harvesting earthworms when the compost is already ripe will be disadvantageous to the worms. De Castro (2006) learned that living in their own casts severely reduced worm population, particularly the youngs. For the African nightcrawler (ANC), it was found that a lower stocking rate of 1 kg/m2 yielded more biomass in 30 days compared to 2 and 3 kg/m2 (Guerrero 2009b). However, this does not necessarily mean that the higher stocking rates would not yield more biomass if harvesting is made much earlier.
Moreover, Guerrero et al. (1984) found that mixture of 75% pig manure + 25% sawdust stocked with 200 g of juvenile ANC resulted to 915% increase in earthworm weight after 30 days. Eight kilograms of the dried mixture of the compost ingredients were placed in wooden boxes measuring 61 cm x 46 cm x 20 cm (0.056 m3), watered to a moisture content of 60-80%, and fermented for one week prior to earthworm stocking. The stocking rate is equivalent to 0.71 kg/m2 or 3.56 kg/m3of compost bed or 0.025 kg ANC per kilogram of dried compost ingredients .
With the increasing demand for animal feed protein bolstered by the continuing growth in human population and food source, the production of vermimeal may be considered as the most economically feasible application of vermiculture. According to Kale (2006), vermiculture has bright prospects in the animal feed industry.
Vermimeal or earthworm meal is a feed preparation consisting of processed earthworm biomass. It is a rich source of animal protein as well as essential amino acids, fats, vitamins, and minerals for livestock, birds and fish. About 5.5 kg of fresh ANC biomass (18% dry matter) is needed to produce 1 kg of vermimeal. It can be packed in plastic bags and stored in a cool dry place out of direct sun for up to 3 months. Proximate analysis of an ANC vermimeal in dry and pulverized form revealed the following composition: 68% crude protein, 9.57% fat, 11.05% nitrogen-free extract, and 9.07% ash (Guerrero 2009b).
Numerous studies on different livestock animals, birds and fishes have shown excellent results of feeding the animals with vermimeal or earthworm meal (Guerrero 2009a). This is not surprising, considering that earthworms are a natural source of nutrition for birds and other animals in the wild.
DE CASTRO A. 2006. Angels in my backyard. In: Guerrero R.D. III, Guerrero-del Castillo MRA (eds.). Vermi Technologies for Developing Countries. Proceedings of the International Symposium-Workshop on Vermi Technologies for Developing Countries. Nov. 16-18, 2005, Los Baños, Laguna, Philippines. Philippine Fisheries Association, Inc. p. 98-105.
GUERRERO RD III. 2009a. Commercial vermimeal production: is it feasible? In: Guerrero R.D. III, Guerrero-del Castillo MRA (eds.). Vermi Technologies for Developing Countries. Proceedings of the International Symposium-Workshop on Vermi Technologies for Developing Countries. Nov. 16-18, 2005, Los Baños, Laguna, Philippines. Philippine Fisheries Association, Inc. p. 112-120.
GUERRERO RD III. 2009b. Vermicompost and Vermimeal Production. MARID Agribusiness Technology Guide. 22 p.
GUERRERO RD III, GUERRERO LA, CARGADO AU. 1984. Studies on the culture of the earthworm Eudrilus euginiae, and its use as feed for Macrobrachium idella and fertilizer source for Brassica compensis. Trans. Nat. Acad. Science & Technol. 6:33-40.
KALE RD. 2006. The role of earthworms and research on vermiculture in India. In: Guerrero R.D. III, Guerrero-del Castillo MRA (eds.). Vermi Technologies for Developing Countries. Proceedings of the International Symposium-Workshop on Vermi Technologies for Developing Countries. Nov. 16-18, 2005, Los Baños, Laguna, Philippines. Philippine Fisheries Association, Inc. p. 66-88.
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