: With an ever increasing population rate; a vast array of biomass wastes rich in
organic and inorganic nutrients as well as pathogenic microorganisms will result from the
diversified human, industrial and agricultural activities. Anaerobic digestion is applauded
as one of the best ways to properly handle and manage these wastes. Animal wastes have
been recognized as suitable substrates for anaerobic digestion process, a natural biological
process in which complex organic materials are broken down into simpler molecules in the
absence of oxygen by the concerted activities of four sets of metabolically linked
microorganisms. This process occurs in an airtight chamber (biodigester) via four stages
represented by hydrolytic, acidogenic, acetogenic and methanogenic microorganisms.
The microbial population and structure can be identified by the combined use of
culture-based, microscopic and molecular techniques. Overall, the process is affected by
bio-digester design, operational factors and manure characteristics. The purpose of
anaerobic digestion is the production of a renewable energy source (biogas) and an odor