Biotechnological approaches have great potential in rapid expansion of livestock through newer, cheaper and reliable means of producing effective vaccines and diagnostics for animal health care management. In this paper, the results of research work done at the National Biotechnology Centre of this Institute, during the past one decade on the application of molecular biological and hybridoma technologies for development of improved diagnostics and effective vaccines against some economically important animal diseases such as rinderpest, bluetongue, bovine herpes virus-1 infection, poxvirus infection, infectious bursal disease, clostridiosis, salmonellosis and pasteurellosis were reviewed.