Apr 29, 2023 · Firmicutes dominated pig and chicken manure composts, while Proteobacteria and Chloroflexes dominated sheep and cattle manure composts (Wan et al. 2021). 7.5.2 Bacteria in Biogas Digester The bacteria used in the pretreatment may be derived from microbial cultures from previous fermentations, sludge, lignocellulosic substrates, rumen fluid, and