DEFENSE MECHANISMS OF PENAEID SHRIMP DURING THE INFECTIVE PROCESS: A REVIEW

The immunity of an organism is the state of natural or acquired resistance against a particular disease or attack by an infectious or toxic agent. In the case of shrimp, defense lies in innate immunity, where humoral and cellular systems play important roles. The defense process begins at the exoskeleton and if this first barrier is exceeded, the pathogen must overcome a number of hemocytes and plasma derived immune factors and a series of events will be generated to achieve their elimination or developing a disease in the host. Thus, the role of hemocytes, signaling, and phagocytosis is discussed in addition to the processes involved in the expression of plasma proteins, phenoloxidase, trypsin, alpha 2-macroglobulin, lysozyme and antimicrobial peptides.