Vibrio penaeicida of Cultured Kuruma Prawns

Category

Category 3 (Host Not in Canada)

Common, generally accepted names of the organism or disease agent

Vibrio sp. PJ, Vibriosis in kuruma prawns. Penaeus killer.

Scientific name or taxonomic affiliation

Vibrio penaeicida. Other species of Vibrio cause disease in cultured shrimp around the world.

Geographic distribution

Japan.

Host species

Penaeus japonicus.

Impact on the host

The disease results in the formation of lesions in the lymphoid organs and gills and has been associated with considerable losses to the prawn industry in Japan. Although considered by de la Peña et al. (1993, 1995) to cause the most serious disease problem in the culture industry of kuruma prawn in Japan, epizootiology is similar to that of other cases of vibriosis in all cultured shrimps and prawns around the world. Specifically, V. penaeicida was demonstrated to be a part of the ubiquitous microflora in apparently healthy P. japonicus and was isolated from their culture environment. However, V. penaeicida will produce disease in a compromised (stressed) host (Genmoto et al. 1996).

Diagnostic techniques

Gross Observations: Affected prawns are characterised by cloudiness of the abdominal muscle, especially in the sixth segment, and brown spots in the gills and lymphiod organs.

Smears: Gram negative, short rods (1.5 to 2 by 0.5 to 0.8 µm) that are straight or slightly curved with a single polar flagellum.

Histology: The brown spots (about 100 µm in diameter) in the gills and lymphoid organs were composed of a bacterial colony surrounded by a melanized zone that was attached to outer multiple layers of haemocytes. Although no extensive necrotic lesions were observed in the heart, hepatopancrease, gonad, and abdominal musculature, small melanized nodules (about 25 µm in diameter) were frequently observed in these organs.

Immunological Assay: Seventy five strains of V. penaeicida shared common antigen(s) with minimal cross-reactivity with Vibrio species and isolates that were pathogenic to fish (de la Peña et al. 1993). An indirect fluorescent antibody technique (IFAT) was found effective as a rapid and reliable diagnostic method but was slightly lower in sensitivity in comparison to the culture method (de la Peña et al. 1992).

DNA Probes: A species-specific sequence in the 16S rRNA was identified and a polymerase chain reaction (PCR)-based method and a 16S rRNA-targeted RT (reverse transcription)-PCR was described by Genmoto et al. (1996).

Culture: Vibrio penaeicida can be isolated from haemolymph, gills, abdominal muscle and lymphoid organs of affected prawns on ZoBell's 2216E agar plates. Colonies, after incubation for 24 hr at 25 °C on this medium, are low convex, entire, circular, cream coloured and translucent. Neither pigmentation nor luminescence were observed. The physiological and biochemical that distinguish V. penaeicida from previously described Vibrio species are detailed by Ishimaru et al. (1995).

Methods of control

Disease outbreaks were most frequent during the summer season when temperatures approximate the optimum temperature for V. penaeicida (27 °C) and when the deterioration of environmental conditions (as a result of high stockingt densities) is evident through the accumulation of organic matter on the pond bottom. Because these conditions cause severe stress to the cultured prawns and render them susceptible to bacterial infection, losses caused by V. penaeicida may be avoided by implementing adequate husbandry practices.

References

Egusa, S., Y. Takahashi, T. Itami and K. Momoyama. 1988. Histopathology of vibriosis in the kuruma prawn, Penaeus japonicus Bate. Fish Pathology 23: 59-65. (In Japanese with English abstract).

Genmoto, K., T. Nishizawa, T. Nakai and K. Muroga. 1996. 16S rRNA targeted RT-PCR for the detection of Vibrio penaeicida, the pathogen of cultured kuruma prawn Penaeus japonicus. Diseases of Aquatic Organisms 24: 185-189.

Ishimaru, K., M. Akagawa-Matsushita and K. Muroga. 1995. Vibrio penaeicida sp. nov., a pathogen of kuruma prawns (Penaeus japonicus). International Journal of Systematic Bacteriology 45: 134-138.

de la Peña, L.D., K. Momoyama, T. Nakai and K. Muroga. 1992. Detection of the causative bacterium of vibriosis in kuruma prawn, Penaeus japonicus. Gyobyo Kenkyu (Fish Pathology) 27: 223-228.

de le Peña, L.D., T. Tamaki, K. Momoyama, T. Nakai and K. Muroga. 1993. Characteristics of the causative bacterium of vibriosis in the kuruma prawn, Penaeus japonicus. Aquaculture 115: 1-12.

de la Peña, L.D., T. Nakai and K. Muroga. 1995. Dynamics of Vibrio sp. PJ in organs of orally infected kuruma prawn, Penaeus japonicus. Fish Pathology 30: 39-45.

Takahashi, Y., Y. Shimoyama and K. Momoyama. 1985. Pathogenicity and characteristics of Vibrio sp. isolated from cultured kuruma prawn Penaeus japonicus Bate. Bulletin of the Japanese Society of Scientific Fisheries 51: 721-730. (In Japanese with English abstract).

Citation Information

Bower, S.M. (1997): Synopsis of Infectious Diseases and Parasites of Commercially Exploited Shellfish: Vibrio penaeicida of Cultured Kuruma Prawns.

Date last revised: December 1997
Comments to Susan Bower

Date modified: