Elimination of microbial pollution of domestic animal excrements using vermicomposting

Abstract

Based on the theoretical knowledge of vermicomposting, a project was realized for the construction of a three-chamber domestic wooden vermicomposter, in which aerobic degradation of three types of animal excrements (cow, pig, dog) using the earthworm Eisenia andrei was carried out. Before laying the individual excrements to the compost batch, the appropriate input samples were taken for the microbiological examination of the biopathogens. After six months, final samples of the final substrate were taken to determine whether proper compost sanitization took place during the vermicomposting process; according to valid legislation, the bacteria Escherichia coli, Enterocococcus sp. and Salmonella sp. were identified as indicator micro-organisms. After the evaluation of the performed laboratory analyses, it was proved that the use of earthworm bioactivity resulted in elimination or at least significant reduction of the concentrations of these bacterial strains in the final vermicompost samples.

Problems associated with vermicomposting of dog excrement in practice using Eisenia andrei

“…was detected in the dog excrement, but not in both piles. Although E. coli decreased in our experiment, in the case of Mudrunka et al (2020) E. coli content did not change (1 × 10 3 CFU g −1 ). They vermicomposted dog excrement with corn meal and decayed grass in outdoor boxes for 5 months.…”

“…content was 3.9 × 10 5 CFU g −1 , and the presence of Salmonella spp. was proven, which is higher, than the values measured by Mudrunka et al (2020), who vermicomposted dog excrement in combination with corn meal and decayed grass. They measured content of E. coli 1 × 10 3 CFU g −1 and 1 × 10 4 CFU g −1 of Enterococcus spp.…”

“…were verified. During the experiment, it was determined whether these microorganisms could actually be eliminated by vermicomposting, because according to Mudrunka et al (2020) earthworms can eliminate the presence of pathogenic microorganisms or contribute to limit the growth of their colonies.…”