The biogas production was different for different substrates because the bacteria responsible for the breakdown of substrate were different. While amylolytic bacteria is good for cow dung, proteolytic bacteria is best for poultry manures. What is good for the farmers, based on this study, is poultry manures but the supply of these substrates can be a problem at times. Cow dung users can have a continuous supply of substrate from animals on a daily basis. This is one reason that the use of cow dung can be recommended for the long term use. For large farms where there is continuous process of rearing poultry, biogas production by this method would be the best as continuous organic loading of reactors would make available adequate biogas for lighting, cooking and other uses.