Abstract
Shrimps live in a complex aquatic ecosystem with numerous other biotic and abiotic factors, especially pathogenic microorganisms, which require the adaptation of prudent protective and survival strategies. As invertebrates, shrimps reply on humoral and cellular innate immune response mechanisms for protection against pathogens. One integral part of the humoral innate immune defence mechanism involves many biomolecules that are constitutively expressed or induced by pathogens. Shrimps, therefore, produce various biomolecules and secondary metabolites for physiological and pathophysiological purposes, most of which also act as effector molecules in immune‐related functions. A growing number of molecules have been identified as essential constituents of the immune arsenal of biomolecules in penaeid shrimps. This review provides a synthesis of important information on penaeid shrimp‐encoded immune‐related molecules with antimicrobial activities, their molecular regulation and importance in shrimp innate immune response. Research gaps would be identified and proposed research themes emphasized for future studies.