The major theme of this book is environmental preservation by controlling release of undesirable greenhouse gases to realize the sustainable development of animal agriculture. Technology exists for the effective collection of methane generated from anaerobic fermentation of animal effluent and its use as a biomass energy source. Fossil fuel consumption can be reduced and there can be increased use of locally available energy sources. In addition, promoting environmentally-conscious agriculture which does not rely on the chemical fertilizer can be realized by effective use of animal manure and compost products.