Virulence of infectious pancreatic necrosis virus (IPNV) isolates from Mexico

Abstract

Infectious pancreatic necrosis virus (IPNV) causes economic losses in Mexican rainbow trout industry. In this study, virulence and genetic fingerprints of Mexican IPNV isolates was investigated for the first time. Two Mexican IPNV isolates were analyzed in rainbow trout fry and the Sp strain was included as high virulence. One of the Mexican IPNV isolate was obtained from diseased fish and the other from fish without clinical signs. The infection was performed using a standardized immersion. Clinical signs were observed at 4 days post infection in fry group infected with strain Sp, two days earlier than in trout infected with IPNV isolates Mexican. Severe lesions were found in 100% of the individuals of Sp group, but only in 25% of each isolated Mexican group. Results suggest that Mexican IPNV isolates are pathogenic, but less virulent than strain Sp. The amino acid motif residues of both Mexican isolates, corresponded to a subclinical disease. Nevertheless, the accumulated motility observed in the field, suggest that other factors play a role in the virulence of the disease.

Molecular Evolution of Infectious Pancreatic Necrosis Virus in China

“…However, high mortality (50–80%) of rainbow trout was caused by the Chinese genogroup V IPNV strains under natural conditions, indicating the high virulence of these Chinese genogroup V IPNV in rainbow trout. A similar phenomenon was found in a previous study, in which IPNV strains that were predicted to be avirulent caused high mortality in rainbow trout [ 6 ]. As we know, the virulent and avirulent definitions connected to the different amino acid positions were mainly resulting from studies in Atlantic salmon.…”

“…Infectious pancreatic necrosis (IPN), a severe viral aquatic disease, was first recorded in salmonids in the Canada in the 1941 [ 1 ]. To date, IPN has been found in many countries, such as France [ 2 ], Croatia [ 3 ], Turkey [ 4 ], Chile [ 5 ], Mexico [ 6 ], Finland [ 7 ], Norway [ 8 ], Spain [ 9 ], Japan [ 10 ], Iran [ 11 ], Korea [ 12 ], Poland [ 13 ], and so on, all of which have caused large economic losses in the salmonid culture industry. IPN virus (IPNV), which belongs to the genus Aquabirnavirus , is an unenveloped virus of about 60–65 nm in diameter [ 14 , 15 ] that forms a crystalline arrangement in host cells [ 16 ].…”

Infectious pancreatic necrosis virus in salmonids: Molecular epidemiology and host response to infection

“…The virus isolated from this outbreak was clustered in Genogroup 1 54 . Subsequent phylogenetic analyses have continued reporting the presence of Genogroup 1 IPNV in Mexico 31,35,42,55,56 . Mexican isolates show a high genetic identity and form a phylogenetic subgroup closely related to the Buhl strain from USA 35,54,55 …”

“…54 Subsequent phylogenetic analyses have continued reporting the presence of Genogroup 1 IPNV in Mexico. 31,35,42,55,56 Mexican isolates show a high genetic identity and form a phylogenetic subgroup closely related to the Buhl strain from USA. 35,54,55 The majority of reports on isolates and phylogenetic characterisations of IPNV have been from Europe due to the large number countries that cultivate salmonids.…”