Effects of rainbow trout (Oncorhynchus mykiss) serum (RTS) on replication of infectionus pancreatic necrosis virus (IPNV)

Hiç infeksiyöz pankreas nekrozu geçirmemiş gökkuşağı alabalığından (Oncorhynchus mykiss) alınan serumun (GAS), infeksiyöz pankreas nekrozu virüsü (IPNV) in vivo ve in vitro replikasyonu üzerine etkilerini belirlemek amacı ile bir dizi deney gerçekleştirildi. In vitro olarak, değişik alt-gruplara ait çeşitli seviyelerde virulense sahip 109 IPNV izolatı, besiyeri içerisinde % 1 GAS içeren ve içermeyen rainbow trout gonad (RTG-2) hücresinde replikasyona tabi tutuldu. Aynı zamanda dere alabalığı (Salvelinus fontinalis); 1 % GAS içeren ve GAS içermeyen besiyeri ile 11 kere tekrar tekrar replikasyona tabi tutulmuş dört virulent IPNV izolatları ile enfekte edildi. Virülensi olmayan IPNV izolatlarının RTG-2 hücrelerinde RTS ile replikasyonları önlenirken, yüksek virülense sahip izolatlarm GAS'a dirençli oldukları görülmüştür. Dahası, in vivo olarak replikasyonun engellenme seviyesinin, izolatın virülenslik derecesi ile ters orantılı olduğu saptanmıştır (P < 0,0001). GAS'ın IPNV replikasyonunu in vivo ve in vitro şartlarda önlemesi virüsün serotipine bağlı olmadığı gibi aynı alt grouptaki IPNV izolatları replikasyonunda bile farlılıklara sebep olabileceği belirlenmiştir.

Gökkuşağı alabalığı (Oncorhynchus mykiss) serumunun (GAS) infeksiyöz pankreas nekrozu virüsü (IPNV)replikasyonu üzerine etkisi

A series of experiments were conducted to determine the effects of rainbow trout serum (RTS), taken from rainbow trout (Oncorhynchus mykiss) that have never experienced infectious pancreatic necrosis disease, on infectious pancreatic necrosis virus (IPNV) in vitro and in vivo. In vitro, 109 IPNV isolates belonging to various subtypes and having various degrees of virulence were passed in the presence and absence of 1% RTS on rainbow trout gonad (RTG-2) cell line. Moreover, brook trout (Salvelinus fontinalis) were challenged with four virulertt Buhl subtype isolates passed 11 times in the presence and absence of 1% RTS. Avirulent isolates of IPNV were inhibited from replication on RTG-2 cells even after a single passage in the presence of 1% RTS, whereas isolates having a high degree of virulence were consistently resistant to RTS. Moreover, in vivo the level of inhibition was related with virulence of the virus (P < 0.0001). Serum inhibition of RTS on IPNV growth in vivo and in vitro is not dependent on the virus serotype. The effect of RTS presence on virus virulence in virus propagation was variable even in the same serotype.

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