Immunostimulants added to injected Aeromonas salmonicida bacterin enhance the defense mechanisms and protection in rainbow trout (Oncorhynchus mykiss)

Dietary intake of levamisole enhances the immune response and disease resistance of the marine teleost gilthead seabream ( L.)

“…The ability of this agent to enhance the response of mammalian T-lymphocytes and macrophages of both healthy (Renoux, 1980) and immunocompromised individuals is well documented (Amery, 1978;Morimoto et al, 1979;Ogunbiyi et al, 1988). In fish, levamisole has only been used in a few studies with the aim of enhancing the nonspecific immune response (Siwicki, 1987(Siwicki, , 1989Kajita et al, 1990;Baba et al, 1993) or as an adjuvant with a vaccine (Anderson & Jeney, 1992;Jeney & Anderson, 1993). The results obtained in such interesting studies point to its potential use in fish as an immunostimulant although special attention must be paid to the doses administered and the timing, as the e#ects of levamisole are closely dose-and time-dependent: high doses of levamisole may suppress the immune responses and low doses may not be e#ective (Anderson et al, 1989;Siwicki et al, 1990).…”

Spontaneous bactericidal and complement activities in serum of rainbow trout (Oncorhynchus mykiss) genetically selected for resistance or susceptibility to furunculosis

“…While these vaccines are useful for Atlantic salmon smolts, injection of fry is hardly practicable and highly time consuming. Field results of furunculosis bath vaccination appear contradictory, and up to now the protective mechanisms triggered by vaccination still remain a point of controversy (Hastings, 1988;Anderson & Jeney, 1992). Thus, other forms of furunculosis control are needed for young fish and an additional means would be the selection of resistant stocks (Chevassus & Dorson, 1990).…”

Evaluation of immune functions of rainbow trout (Oncorhynchus mykiss)—how can environmental influences be detected?

“…After binding of antigens, different effector functions are initiated: enhanced phagocytosis of the opsonized antigens by macrophages, complementdependent cytolysis, antibody-dependent cell-mediated cytotoxicity via Fc-receptors on natural cytotoxic cells, and virus neutralization by blocking entry into susceptible cells (Fig. 1) (Kaattari et al, 2002;Boudinot et al, 1998;Hattenberger-Baudouy et al, 1995;Emmenegger et al, 1995;Anderson and Jeney, 1992;Sharp et al, 1992). Inhibition of various functions of antibodies therefore results in an increased susceptibility to infectious diseases.…”