EN
Immunostimulatory effects of levamisole and TFX-Polfa have been compared in carp (300 fish of a body weight 150-200 g) under field conditions. Just after being taken from the fishery the carps were exposed to a 1 h medicated bath (10 mg of levamisole/1) and then after 5 weeks they were fed levamisole at a dose of 5 mg/kg of body weight every second day for 2 weeks. After the fish were caught TFX-Polfa was injected intraperitoneally once at a dose of 0,2 mg/fish. During a span of 24 weeks clinical observations were made and immunological profiles were determined. The number of leukocytes and neutrocytes in 1 pi of blood, metabolic activity of neutrocytes (NBT) and activity of lysozyme (spectrophotometric method) were estimated. It was found that a single immunostimulation of the carp with levamisole activated immunemechanisms in spiring whereas a second dose of levamisole in fodder also activated the immuneprotective mechanisms in summer and autumn. A single dose of TFX-Polfa increased immunologic activity of the carp during the whole period of observation. The level of this activity was higher than that after a second stimulation by levamisole.