This book provides essential information on the various roles of probiotics in animals. Over the past few decades, the prevalence of analysis regarding probiotic strains has significantly grown in most regions of the world. The use of probiotic strains in animal production may decrease numerous complications caused by growth promoter, antibiotics therapy and problems from improper management. Probiotics are particular strains of microorganisms, which when served to animals or humans in suitable amounts, have an advantageous impact, enhancing health or decreasing the risk of getting sick. The book would serve as an important source of reference to a wide range of readers.