The most requested blood agar plate, Tryptone Soy Agar (casein soy bean digest agar) with defibrinated sheep blood is suitable for the cultivation of fastidious aerobic and anaerobic bacteria, the latter of which can be grown either in deep cultures or by incubation under anaerobic conditions. The combination of casein digest and papaic digest of soybean meal leads to optimal growth due to synergy between the protein supply of casein and the carbohydrate supply of soybeans. Sterile defibrinated sheep blood used to enrich the medium produces the hemolysis characteristics of different bacteria, such as streptococci, listeria, hemolytic Staphylococcus, Escherichia coli and Pseudomonas.