This book is one of the cornerstones of poultry production. In fact, it is one of the aspects that most influence production parameters in the poultry industry. In broilers, the optimum time ofEncuadernación: Cartoné vaccination should aim at obtaining the maximum meat yield. In layers and breeders, both time and the route of administration have an influence in the quality of egg shells and the number of eggs per laying, among others.