Expression of innate immunity genes in kuruma shrimp Marsupenaeus japonicus after in vivo stimulation with garlic extract (allicin)

In recent times, attention has focused on immunostimulants and plant products which could have beneficial effects in disease control. At present, the application of immunostimulants has been considered a more effective approach to health management in aquaculture through the enhancement of immune capability and disease resistance in shrimp. Garlic possesses bactericidal property against bacteria and can inhibit the growth of protozoa as well as gregarine infection in cultured shrimp. However, its effect on viral disease infection has not been well studied and requires further investigation. Garlic can also stimulate shrimp haemocytes as determined by cellular immune responses (phagocytic activity, superoxide anion production and phenoloxidase activity) suggesting that the immune-stimulatory properties of garlic will be useful for improvement of shrimp health. Here, we determined the expression of the immune-related genes Penaeidin, Crustin, Lysozyme, Toll-like, and tumour necrosis factor in kuruma shrimp, upon stimulation with allicin extract. The expression of these factors was measured for the first time and was found to be elevated in intestine and lymphoid organ after in vivo stimulation for 3, 12, 24 and 48 h. We conclude that garlic can be used in shrimp culture as an alternative to antibiotics or chemotherapeutic agents; however, further research is needed under field conditions.