The immune system of fish

Abstract

The immune system of fish shows similarities to mammalian models, being intensively studied in veterinary and medical research. Fish culturists have been interested in using the animal's natural defense mechanisms for protecting stocks against diseases since fish farming began. The immune system contribiutes to the maintenance of the physiological integrity of the animal and includes those nonspecific defense mechanisms that are part of a normal fish and act as natural barriers to entry of microorganisms and do not require prior contact with the inducing agent to elicit a response. The specific immune response of fish is an activated system which means time is needed to induce the protection, as the complex chain of pathways are activated. Hopefully, the nonspecific defense mechanisms can delay the growth of invaders until the specific immune response has time to develop. The initiation of the specific immune response is controlled by phagocytic cells involved in particle or antigen uptake.