Change of Immunological Indices in Carps (Cyprinus carpio L.) Following Rhabdovirus Carpio Injection

Abstract

At present, it is obvious that spring viremia of carp (SVC) is a viral disease inflicting considerable damage to fish farming, especially to carp breeding (Lobuntsov 1986; Lobuntsov and Rudikov 1979). Despite controversial viewpoints regarding the etiology of this pathology, a number of authors agree that it is triggered by a virus and then developed due to bacteria acting as a secondary infection (Osadchaya 1984; Osadchaya and Prosyanaya 1984; Osadchaya et al. 1977). By lysing the cells, the virus causes pathological changes in organs and tissues of fish which create favourable conditions for secondary microflora development (Rudikov 1985). It is established that 1-year-old carps infected by live virus acquire immunity, but unlike adult species, their defence reaction is not often dependent on neutralizing activity of serum antibodies (Fijan et al. 1977; Fijan et al. 1977). In the natural environment, viral infection often leads to the extinction of part of the stock, because the temperature optimum of viral replication is lower than the temperature range favourable for the production of antibodies (Ahne 1980; Ahne 1984).