Vermiculture: a potential role in the management of broiler litter in Australia?

Abstract

With increasing human population, the demand for quality animal meat products is increasing, and intensive chicken meat (broiler) production is contributing to some of this demand. A major output from commercial farms is broiler litter (litter) which has relatively high plant nutrient concentrations compared to other animal manures. This makes litter valuable for plant production and hence it is mainly utilised and disposed of on land. However, the suitability of land within cost effective distances from growers is becoming an increasing problem worldwide, with reduced suitability due to potential environmental and bio-security risks. Therefore it is important to develop disposal mechanisms that can provide the industry with an alternative to the direct land application of litter. The present research was undertaken to gain an understanding of the potential role vermiculture could have in the management of litter in Australia. Vermiculture has the potential to produce both humic rich vermi-compost (vermicast) and meatmeal (vermimeal) from litter. Traditionally vermiculture has primarily been adopted to produce vermicast, a recognised valuable organic fertiliser. However, the production and processing of earthworms into vermimeal is becoming an increasingly viable component. Both of these outputs potentially render vermiculture a value-adding opportunity for the Australian poultry industry, whilst providing an alternative disposal option for litter. That being said vermiculturalists have tended to avoid nutrient rich or 'hot' wastes due the system becoming unstable, resulting in earthworm mortality. Uniquely, this research focused on using fresh litter as the sole food source for earthworms ('Eisenia andrei') in a batch flow system.