Abstract
Recent investigations in fish have revealed the dietary dependence of immunosurveillance. This report describes the evidence for dietary link of non-specific cytotoxic activity of natural-killer cells in rainbow trout. Fish were reared for varying periods in different experiments designed to determine the role of protein, essential fatty acid and zinc. Later the immune response was recorded by measuring the release of 51 Cr from labelled P815 mouse mastocytoma target cells after 8h incubation. Leucocytes isolated from the head kidney of experimental fish were employed as effector cells.
Dietary protein does not have any effect on the natural-killer like activity of the leucocytes. The activity was low when the diets were deficient in essential fatty acid and zinc.
