Bacterial and Viral Diseases of Kuruma Shrimp (Penaeus japonicus) in Japan.

Abstract

Three major disease problems that have been reported in kuruma shrimp (Penaeus japonicus) culture in Japan are vibriosis, penaeid acute viremia (PAV) and baculoviral mid-gut gland necrosis (BMN).Vibriosis in kuruma shrimp was first reported in 1985, and since then it has seriously damaged the culture of this species in Japan. The characteristic signs of this disease are brown spots in the lymphoid organs and in the gills, and cloudiness of muscle in the sixth abdominal segment. This bacterium was identified as a new species in the genus Vibrio and named Vibrio penaeicida.Outbreaks of PAV, causing serious mortality of kuruma shrimp and being closely related to white spot baculovirus infection of penaeid shrimp, have been reported in Japan since 1993. Diseased shrimp show white spots in the carapace and reddish discoloration of the body. A non-occluded bacilliform virus, penaeid rod-shaped DNA virus (PRDV), was observed under the transmission electron microscope. In order to detect the virus, primers for the polymerase chain reaction (PCR) were developed. PCR has been successfully used for diagnosis and detection of carrier state crustaceans.BMN is the epizootic of kuruma shrimp larvae in Japan. The typical sign of this disease is a white-turbid mid-gut gland that shows remarkable cellular necrosis and no inclusion body in the section. Rod-shaped particles, resembling baculovirus, are found in the affected nuclei under the electron microscope.Attempts were made to evaluate the efficacy of immunostimulants to kuruma shrimp as potential agents for the prophylaxis of vibriosis and PAV. The oral administration of a peptidoglycan derived from Bifidobacterium thermophilum is effective in preventing these diseases in kuruma shrimp.

Proteinaceous exotoxins of shrimp-pathogenic isolates of Vibrio penaeicida and Vibrio nigripulchritudo

“…Vibrio penaeicida strains KH-1 and AM101 were involved in a major decline of the shrimp production in Japan (Takahashi et al, 1998) and New Caledonia (Costa et al, 1998), respectively. Our results showed that living strain KH-1 exhibited a very weak mortality rate (12%) compared to strain AM101 (54%) 4 days after infection, at a dose of 10 4 cfu mL -1…”

“…Costa et al (1998) showed a LD 50 of 1.3 × 10 4 cfu mL -1 for shrimp (L. stylirostris) by the bath challenge. De la Peña (1993) and Takahashi et al (1998) reported that Vibrio sp PJ, later named V. penaeicida (Ishimaru et al, 1995), showed a LD 50 of 10 2 and 10 3 cfu org -1 in juvenile P. japonicus when injected intramuscularly. Prayitno and Latchford (1995), Hameed (1995), Harris and Owens (1999), and Saulnier et al (2000b) showed that the virulence of Vibrio species is related to the Vibrio strains, method of infection and host factors (species, age, physiological state).…”

“…Las cepas KH-1 y AM101 de V. penaeicida estuvieron involucradas en el mayor declive de la producción de camarón en Japón (Takahashi et al, 1998) y en Nueva Caledonia (Costa et al, 1998), respectivamente. Los resultados de esta investigación demuestran que la cepa viva KH-1 genera un bajo porcentaje de mortalidad (12%) al compararse con la cepa AM101 (54%), 4 días después de la infección a una dosis de 10 4 ufc mL -1 .…”

“…Costa et al (1998) mostraron una DL 50 de 1.3 × 104 ufc mL -1 para camarón (L. stylirostris) en un ensayo por inmersión. De la Peña (1993) y Takahashi et al (1998) reportaron que Vibrio sp PJ, posteriormente llamado V. penaeicida (Ishimaru et al, 1995), mostró una DL 50 de 10 2 y 10 3 ufc org -1 en juveniles de P. japonicus, cuando éstos fueron inyectados intramuscularmente. Prayitno y Latchford (1995), Hameed (1995), Harris y Owens (1999) y Saulnier et al (2000b) demostraron que la virulencia de las especies de Vibrio está relacionada con la cepa de Vibrio, el método de infección y las características del huésped (especie, edad, estado fisiológico).…”

Rapid and sensitive PCR detection of Vibrio penaeicida, the putative etiological agent of Syndrome 93 in New Caledonia

“…Vibriosis caused by Vibrio penaeicida is a disease that affects commercially reared shrimp Penaeus (Marsupenaeus) japonicus in Japan and results in great economic loss (Sano & Fukada 1987, d e la Pena et al 1993, Takahashi et al 1998. Since 1993, mortality outbreaks have been seasonally observed in semi-intensive Penaeus (Litopenaeus) stylirostris grow out ponds in New Caledonia, principally during winter when water temperatures rapidly drop (Mermoud et al 1998).…”