Comparison of Immune Response of Litopenaeus vannamei Shrimp Naturally Infected with Vibrio Species, and after Being Fed with Florfenicol

The outbreaks caused by Vibrio spp. are a notable threat to the potential growth of economy penaeid culture, which is still controlled administration antibiotics. At first, infected group was subjected phenotypic bacteriological examination with subsequent molecular identification via 16S rRNA gene sequencing, confirmed four strains spp., V. atlanticus, natriegens, alginolyticus, and harveyi, from moribund-infected shrimp during mortality events in an Egyptian hatchery. To better understand defense mechanism most effective antibiotic against strains, immune responses were compared evaluated Litopenaeus vannamei broodstock after being fed 5 mg kg?1 florfenicol antibiotic, first determined through vitro antibiogram tests. Therefore, our study aimed determine response L. infection hatcheries medication. parameters assessed total differential hemocyte count (THC), granular cells (GC), semi-granular (SGC), hyaline (HC). As well as metabolic enzymes: alanine aminotransferases (ALT), aspartate (AST), alkaline phosphatase (ALP), acid (ACP), lysozyme activity; antioxidant index, such superoxide dismutase (SOD) glutathione (GSH); phagocytic assay; changes reactive oxygen species (ROS); bactericidal activity hemolymph control, infected, treated groups. Further evaluation mRNA expression levels prophenoloxidase (LvproPO), toll-like receptor 1 (LvToll1), haemocyanin (LvHc) genes performed hepatopancreas same A significant drop THC, GC, SGC, HC counts, activities, assay, ROS, SOD, GSH represented control shrimp; however, marked increase ALT, AST, ALP, ACP observed. These activities significantly restored shrimp. Nevertheless, no noted transcriptional LvproPO LvToll1 when suppression LvHc noted. Our We concluded that medicated feed could be controlling vibriosis ameliorating