Effects of Immune-induced Perinereis linea on Growth Performance and Imuune activity of the Litopenaeus vannamei

Antimicrobial peptides (AMPs) are molecular factors in innate immunity and are believed to play a key role in invertebrate host defence. We found that Micrococcus luteus peptidoglycan (PGN) was best at inducing lugworm AMPs. After stimulating lugworms with PGN from M. luteus, AMP-induced lugworm powder was added to feed that was fed to whiteleg shrimp. The effects of whiteleg shrimp on growth performance, serological components, and bacterial infection were investigated. We fed whiteleg shrimp AMP-induced lugworm powder at 0% (control), 0.05%, 0.1%, 0.5% and 1% ratios for 8 weeks. The specific growth rates (SGR) were significantly increased in all tested groups compared with the control. In addition, it was confirmed that the feed conversion ratio (FCR) and protein efficiency ratio (PER) were improved in a concentration-dependent manner. In the 2nd, 4th, 6th, and 8th weeks after the start of feeding, total cholesterol (TCHO), glucose (GLU), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels were tested, and no significant changes were detected in any of the results. The lysozyme level showed a significant increase in the 1% experimental group, and the cortisol level did not significantly change in any of the experimental groups. After 8 weeks of the feeding trial, whiteleg shrimp were infected with Vibrio harveyi and observed for 20 days. The 0.05% test group showed the lowest mortality rate, and the 1% test group showed significantly higher mortality than the control group on the 5th day.