Over decades, antibiotics have routine been added in poultry diets at low doses to maximize growth and to control intestinal pathogens that accidentally contaminate poultry products during processing. Unfortunately, such practice has favored resistance to antibiotics among human pathogens. Consequently, human infections are more difficult to treat. There is, now, increasing interests to discontinue the use of antibiotics in the nutrition of livestock animals. There is, therefore, an urge to develop biological products that could sustain efficiency of production and safety of poultry meat and eggs for human consumption in the absence of antibiotics. Prebiotics are considered as potential alternatives to antibiotics, but scientific evidences are lacking. This book helps elucidating the mechanisms by which prebiotics, in comparison to antibiotics, can confer better protection against invading pathogens in chickens. This book is greatly relevant to professionals, industrialists and farmers who have major interests in the use of antibiotics and prebiotics to improve animal health and safety of animal products.