Passive immunization of salmonids against furunculosis and vibriosis with chicken egg yolk immunoglobulins (IGY)

Passive immunization of coho salmon (Oncorhynchus kisutch) and rainbow trout (O. mykiss) was investigated using specific immunoglobulins (IgYs), which were raised in domestic chickens (Gallus domesticus) and extracted from their egg yolk, against fish pathogens of either Aeromonas salmonicida or Vibrio anguillarum . Oral treatments of these fish with either anti-A. salmonicida or anti-V. anguillarum IgY did not provide passive immune protection. When intraperitoneally (IP) injected, anti-V. anguillarum IgY provided significant passive immune protection against V. anguillarum whereas anti-A. salmonicida did not provide protection against A. salmonicida. In the latter case, it appears the A. salmonicida was grown under conditions that restricted the formation of cell surface antigens against which a protective antibody could be raised in chickens.; IgY from unvaccinated chickens provided moderate passive immune protection against V. anguillalrum challenge as compared to IgY from chickens vaccinated with this bacterin that provided a strong passive immune protection. These results imply that there are common cell surface antigens of V. anguillarum on other bacteria to which the chickens were normally exposed.; IP injection of anti-V. anguillarum IgY into rainbow trout provided significant and undiminished immune protection against a lethal challenge by V. anguillarum for up to 2 weeks. Passive immune protection against V. anguillarum in rainbow trout was provided when the total IgY concentrations in rainbow trout were between the tested range 2.5 x 10-2 and 4.0 x 10-3 mg/mL serum. If anti-V. anguillarum immunoglobulins were assumed to be 10% of the total IgY, the equivalent concentrations of this specific IgY would be between approximately 2.5 x 10-3 and 4.0 x 10-4 mg/mL serum. (Abstract shortened by UMI.)...