SHRIMP EXTRACT IMMUNE STIMULANT HAD UP REGULATED THE EXPRESSION OF ANTI-LIPOPOLYSACCHARIDE FACTOR (ALF) OF PENAEUS VANNAMEI

Abstract

Pacific white shrimp (Penaeus vannamei) is an important aquatic animal culture of Thailand. In 2018, its production had reached more than 345,000 tons which could generate several farming activities and incomes to the farmers and finally increase the export values to Thailand more than 60,000 million baht per year. However, in 2012, it has been reported about an outbreak of infectious disease named as acute hepatopancreatic necrosis disease (AHPND) in Thailand and the causative agent came from Gram negative bacterium, Vibrio parahaemolyticus specific isolates (VPAHPND isolates). This pathogen produces two important types of toxin including PirA and PirB which affect hepatopancreas of shrimp and cause sudden mass mortalities. The present study aimed to solve the problem of VPAHPND infection by using immune stimulant strategies. Shrimp shell obtained from frozen industry was employed as the main source to extract lipid metabolites and used as the immune stimulant. Shrimp fed with lipid metabolites mixed feed for 1 week were subjected to investigate an immune gene expression by RT-PCR analysis. Compared with a control group, shrimp fed with immune stimulant feed formula showed the up regulation of anti-lipopolysaccharide factor (ALF) gene by 1.3-fold. This result indicated that lipid metabolites extracted from shrimp shell can induce the expression of ALF, one of the essential immune genes in shrimp and it had high potential to further apply for protection of VPAHPND infection in shrimp aquaculture.