Pathogenicity of Yersinia Ruckeri in Rainbow Trout (Oncorhynchus Mykiss)

Document Type : Aquatic Animal Health Management

Authors

1 Department of Aquatic Animal Health, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran

2 Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran

3 Department of Pathology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran

Abstract

BACKGROUND: Yersiniosis or enteric redmouth disease (ERM), caused by Yersinia ruckeri, is a serious bacterial disease in the farmed salmonids that causes economic problems in this industry. OBJECTIVES: This study was aimed to assess the experimental pathogenicity of Yersinia ruckeri in Rainbow trout (Oncorhynchus mykiss). METHODS: Two hundred Rainbow trout weighting 100-120 g, challenged with different strain of Yersinia ruckeri were obtained from affected trout farms using intra peritoneal injection route at a concentration of 108 cells/ml (0.1 mL per fish) to evaluate the virulence of these isolates. Each treatment group included 10 fish in two replicates and control fish received 0.1 mL sterile normal saline (0.9% NaCl). Following the intra peritoneal challenge, macroscopic and microscopic findings were determined. The most virulent strain was then used to determine the lethal concentration (LD50) using both intra peritoneal and bath method at dilutions of 103-1010 cells/mL. RESULTS: Macroscopically, anorexia, lethargy, circular swimming near the surface, blackening of skin, exophthalmia, hyperemia and hemorrhage in different parts of body, anal prolapse, enlarged liver and spleen were observed. Microscopically, hyperemia of hepatic sinusoids and vessels, necrosis and vacuolization of hepatocytes, increase in the abundance of macrophage centers in kidney, dilatation of Bowman’s space, degeneration and necrosis of kidney tubules, severe necrosis and detachment of intestinal villi, hyperplasia and clubbing of epithelial cells of secondary lamellae, spleen cell necrosis, goblet cell hyperplasia and thickening of epidermis layer in the tongue mucosa were observed.  The LD50 of intra peritoneal injection was calculated 1.2×106cells per fish 48 h post challenge. In bath route, LD50 was obtained 5×108 Cells/ml after 96 h. CONCLUSIONS: The results obtained from this study show virulence diversity of native strains.

Keywords

References

 
 
Agius, C., Roberts, R. J.  (2003) Melano-macrophage centres and their role in fish pathology. J Fish Dis. 26: 499-509.##
Austin, D.A., Robertson, P.A.W., Austin, B. (2003) Recovery of a new biogroup of Yersinia ruckeri from diseased rainbow trout (Oncorhynchus mykiss, Walbaum). Syst Appl Microbiol. 26: 127-131.##
Avci, H., Birincioglu, S.S. (2005) Pathological findings in rainbow trout (Oncorhynchus mykiss Walbaum, 1972) experimentally infected with Yersinia ruckeri. Turk J Vet Anim Sci. 29: 1321-1328.##
Busch, R.A., Lingg, A.J. (1975) Establishment of an asymptomatic carrier state infection of enteric redmouth disease in rainbow trout (Salmo gairdneri). J Fish Res Board Can. 32: 2429-2432.##
Daniely, M.L., Goodwin, A.E., Killian, H.S. (1999) Epizootics in farm raised channel catfish, Ictalurus punctatus (Rafinesque), caused by the enteric redmouth bacterium Yersinia ruckeri. J Fish Dis. 22: 451-456.##
Davies, R.L. (1991) Virulence and serum-resistance in different clonal groups and serotypes of Yersinia ruckeri. Vet Microbiol. 29: 289-297.##
Eissa, A.E., Moustafa, M., Abdelaziz1, M., Ezzeldeen, N.A. (2008) Yersinia ruckeri infection in cultured Nile tilapia, Oreochromis niloticus, at a semi-intensive fish farm in lower Egypt. Afr J Aquat Sci. 33: 283-286.##
Ferguson, H.W. (2006) Systemic pathology of fish. In: Systemic Pathology of Fish: A Text and Atlas of Normal Tissues in Teleosts and Their Responses in Disease. Ferguson, H.W. (ed.).  Scotian Press, London. p. 17-18.##
Fouz, B., Zarza, C., Amaro, C. (2006) First description of nonmotile Yersinia ruckeri serovar I strains causing disease in rainbow trout, Oncorhynchus mykiss (Walbaum), cultured in Spain. J Fish Dis. 29: 339-346.##
Furones, M.D., Rodgers, C.J., Munn, C.B. (1993) Yersinia ruckeri, the causal agent of enteric redmouth disease (ERM) in fish. Annu Rev Fish Dis. 3: 105-125.##
Gudmundsdottir, B.K., Gudmundsdottir, S., Gudmundsdottir S., Magnadottir B.) 2014) Yersiniosis in Atlantic cod, Gadus morhua (L.), characterization of the infective strain and host reactions. J Fish Dis. 37: 511-9.##
Hastein, T., Gudding, R., Evensen, O. (2005) Bacterial vaccines for fish: an update of the current situation worldwide. Dev Biol. 121: 55-74.##
Joh, S. J., Kweon, C. H., Kim, M. J., Kang, M. S., Jang, H., Kwon, J. H. (2010) Characterization of Yersinia ruckeri isolated from the farm-cultured eel Anguilla japonica in Korea. Korean J Vet Res. 50: 29-35.##
Mahjoor, A.A., Akhlaghi, M. (2012) Study of Rainbow Trout organs naturally infected with Enteric Redmouth Disease. Asian J Anim Sci. 6: 147-153.##
Rickaert, J., Bossier, P., D’Herde, K., Diez-Fraile, A., Sorgeloos, P., Haesebrouck, F., Pasmans, F. (2010) Persistence of Yersinia ruckeri in trout macrophages.  Fish Shellfish Immunol. 29: 648-655.##
Rigos, G., Stevenson, R. (2001) The effect of antibiotic treatment on the establishment of persistent infection with Yersinia ruckeri Serovar II in rainbow trout Oncorhynchus mykiss (Walbaum). Aquacult Int. 9: 247-253.##
Romalde, J.L., Toranzo, A.E. (1993) Pathological activities of Yersinia ruckeri, the enteric redmouth (ERM) bacterium. FEMS Microbiol Lett. 112: 291-300.##
Rucker, R.R. (1966) Redmouth disease of rainbow trout (Salmo gairdneri). Bull Off  Int  Epizoot. 65: 825-830.##
Soltani, M., Fadaii F., Mehrabi, M.R. (1999). First report of a yersiniosis-like infection in Iranian farmed rainbow trout. B Eur Assoc Fish Pathol. 9: 173-177##
Soltani, M., Mousavi, S.H., Ebrahimzadeh Mousavi, H.A., Mirzargar, S., Shafiei, S.H., Shohreh, P., et al. Molecular (2014) study of Yersinia ruckeri distribution, the cause of yersiniosis in farmed rainbow trout in Iran. Ir J Vet Med. 40: 59-68.##
Tobback, E., Decostere, A., Hermans, K., Haesebrouck, F., Chiers, K. (2007) Yersinia ruckeri infections in salmonid fish. J Fish Dis. 30: 257-68.##
Tobback, E., Decostere,  A., Hermans, K., Ryckaert, J., Duchateau, L., Haesebrouck, F., Chiers, K. (2009) Route of entry and tissue distribution of Yersinia ruckeri in experimentally infected rainbow trout Oncorhynchus mykiss. Dis Aquat Org. 84: 219-228.##
Valtonen, E.T., Rintamäki, P., Koskivaara, M. (1992) Occurrence and pathogenicity of Yersinia ruckeri at fish farms
Journal of Veterinary Research
Volume 73, Issue 1
March 2018
Pages 1-8

Files

Share

How to cite

Statistics