Dynamics of Vibrio sp. PJ in Organs of Orally Infected Kuruma Prawn, Penaeus japonicus.

Abstract

Kuruma prawns (Penaeus japonicus) were experimentally infected with Vibrio sp. PJ by the oral administration. At 3, 6, 8, 10, 12, 24, 36, and 48 h post-inoculation, prawns were sampled to determine the cell number and distribution of the pathogen in various organs by viable cell count and the enzyme-labeled antibody technique (ELAT).Vibrio sp. PJ was detected by culture method from the stomach and hemolymph at 3 h and from the hemolymph and almost all the organs sampled at 6 h post-inoculation. However, the pathogen started to disappear from all the organs from 8 h to 12 h. At 12 h, it reappeared in the hepatopancreas and lymphoid organs. Twenty-four hours after inoculation, the pathogen was detected from the hemolymph and all the organs except the stomach and gills, and at 36 h the pathogen was found distributed in all the organs. Principally the same distribution pattern of the pathogen was found by ELAT.These results seem to indicate that the process in the pathogenesis of Vibrio sp. PJ infection in orally challenged kuruma prawns consist of five stages namely, establishment of the pathogen, distribution of the pathogen, clearance of the pathogen by host prawn, secondary multiplication of the pathogen, and systemic infection. The results also suggest that the pathogen multiplied in the stomach in the establishment stage and in the hepatopancreas and lymphoid organs in the secondary multiplication stage.

Analysis of microbiota in the stomach and midgut of two penaeid shrimps during probiotic feeding

“…The digestive tract of shrimp is one of the main routes of pathogen infection. According to previous studies, pathogenic bacteria including AHPND strains of V. parahaemolyticus colonize in shrimp stomach and cause shrimp death 21 , 40 , suggesting the importance of microbiota in the stomach 23 . The use of probiotics is thought to be a promising approach for sustainable aquaculture by preventing diseases and reducing the use of antibiotics 25 , 26 , 41 .…”

“…Hybridization was done for 17 h at 65 °C and a Custom Gene Expression Microarray GE 8 × 15 k (Agilent Technologies, USA.) containing 15,745 probes for known genes and expressed sequence tags from L. vannamei 40 . The hybridized slide was washed and scanned immediately using a DNA Microarray Scanner with SureScan High-Resolution Technology (Agilent Technologies, USA).…”

Evaluation of Bacillus spp. as Potent Probiotics with Reduction in AHPND-Related Mortality and Facilitating Growth Performance of Pacific White Shrimp (Litopenaeus vannamei) Farms

“…The stomach microbiota of penaeid shrimp may play a crucial role in protecting against bacterial infections. Vibrio bacteria, such as VP AHPND and Vibrio penaeicida , colonize the shrimp’s stomach during the initial stages of infection [ 19 , 20 ]. Moreover, in contrast to mammalian animals, shrimp stomachs host a diverse range of bacteria [ 21 , 22 ], with variations observed in the presence or absence of AHPND development [ 1 , 23 ].…”