A comparison of composting and vermicomposting for the disposal of poultry waste

Abstract

Context Poultry products, mostly meat and eggs, provide affordable quality foodstuffs to human populations in Nepal. However, the poultry industry’s by-products, such as litter and offal, also generate potential environmental and human health issues and need a sustainable method of management. Aims The present study compared the effectiveness of vermicomposting by using an exotic earthworm species Eisenia fetida, or effective microorganism-based (EM) composting, of poultry litters in the Terai region of Nepal. Methods Four types of poultry litter, namely, broiler cage litter (parent stock litter), broiler deep litter, commercial layer cage litter and layer deep litter, each combined with earthworms (vermicompost) or effective microorganisms, were subjected to decomposition in beds. A completely randomised design in a 4 × 2 factorial arrangement (poultry litters by Eisenia fetida or effective microorganism) with three replicates per treatment was applied. Key results Macronutrient concentrations, and reduction of the carbon:nitrogen ratio were significantly greater in vermicompost than EM compost. In addition, reduction of the carbon:nitrogen ratio was more significant following vermicomposting for broiler and layer cage litter than in other treatments. The highest initial concentration of N was found in layer cage litter (2.1%) and the lowest in layer deep litter (1.3%) and these increased to 1.5–3.4% and 1.7–1.8% in vermicompost and EM compost respectively. Available phosphorus increased by two- to three-fold in most vermicomposted poultry litters in comparison to initial poultry litters, and a two-fold increase in potassium was likewise achieved. Consistent with these results, worm biomass was significantly higher in layer cage litter and broiler cage litter than in deep litter. More cocoons were evident in layer cage litter, and lowest numbers of cocoon formation were observed in broiler deep litter. Conclusions This comparative study showed that vermicomposting is superior to EM composting for bioconversion of poultry litters into value-added compost. Implications With the adoption of this result, the poultry industry in Nepal could become more sustainable.

Vermicomposting by Bio-Recycling of Animal and Plant Waste: A Review on the Miracle of Nature

“…Earthworms comminute the substrate, increasing the surface area available for microbial decomposition, which is essential for efficient vermicomposting. When this fractioned organic matter passes through the gut, it interacts with intestinal-associated bacteria and digestive enzymes before partly digesting and entering the intestines as casts, during which the microbes start the decay phase and contribute to the maturation stage (Aslam et al, , 2021Joshi et al, 2020).…”

Sustainable management of diseases and pests in crops by vermicompost and vermicompost tea. A review

“…These organic amendments are reported to enhance the growth of plants by providing essential nutrients, improving beneficial microorganisms, and managing harmful pests and diseases (Stewart-Wade 2020), and may have a long-term effect on agroecosystem productivity and sustainability (Mas-Carrió et al 2018;Domínguez et al 2019). Both composts and vermicomposts are used for the growth and development of crops; however, due to some negative aspects of compost such as higher electrical conductivity, existence of more pathogens, low nutrient concentrations, and higher phytotoxicity (García-Gómez et al 2002;Bloem et al 2017;Joshi et al 2020), vermicompost is preferred for plant growth by most of the consumers. As an organic fertilizer and a bio-control agent, vermicompost has been shown to be more effective with respect to its counterpart, compost (Edwards and Arancon 2004b).…”

“…However, vermicompost products are mostly used in growing horticultural crops. As vermicompost can be applied to any agricultural crop, the same can also be produced from any type of organic waste like municipal waste (Soobhany et al 2017b), tannery waste (Ravindran et al 2019), agricultural waste (Kamalraj et al 2017), horticultural waste (Mendoza-Hernández et al 2014), animal manure (Szczech and Smolinska 2001), poultry waste (Joshi et al 2020), and aquatic waste (Hussain et al 2017). However, it has been reported that cow dung is the best organic waste to produce vermicompost (Blouin et al 2019).…”

“…In the case of vermicompost, microbial populations are dominated by mesophilic bacteria and fungi that produce nitrogen as nitrate, a more suitable form for plants, compared to composting where thermophilic bacteria produce nitrogen as ammonia (Atiyeh et al 2000b;Edwards and Arancon 2004b;Jayashree et al 2008). A comparative study was performed on the conversion of the same material by composting and vermicomposting and it was reported that vermicompost contains significantly higher macronutrient concentrations compared to compost (Joshi et al 2020). It was stated that the higher NPK content was due to the microbial activity present both within the gut of earthworms and in the earthworm cast.…”

“…This improvement in vermicompost may be because of the favorable conditions for the growth of microbes in the digestive tract of worms and by the ingestion of nutritious organic waste which provides energy and acts as a substrate for the growth of microbes (Ravindran et al 2016). Other authors reported that the unexpected lower microbial activities in compost might be due to the formation of anaerobic niches, leading to the production of gases such as methane and N oxide in beds that reduce the microbial populations (Joshi et al 2020).…”