Changes in hemopoietic tissue of rainbow trout under influence of stress

摘要: As in higher vertebrates, stress increases the susceptibility of fishes to disease. This effect is accompanied by changes circulating white blood cells: number lymphocytes decreases while granulocytes increases. Investigations were therefore undertaken determine what ways induces hemopoietic organs, particularly spleen and head kidneys rainbow trout Salmo gairdneri Handling social conflict used as stressors. These psychic stimuli are typically encountered aquaculture under laboratory conditions. Under influence both stressors hemopoiesis kidney disturbed. Blast cells become rare or disappear completely from tissue. The numbers mature, intact PMN small lyrnphocytes also decrease. Hypertrophic macrophage-like with vacuolized cytoplasm appear increasing numbers. They develop mainly immature reticuloendothelial cells. swell continuously undergoing evident disintegration. At same time, destruction erythrocytes proceeds at an increased rate. high may indicate that stresson initially stimulate defense mechanisms thereby serve adaptive function. Possibly, continued stress, their proteolytic enzymes begin damage body's own decreased production new immune-competent still present seem finally contribute disease stress.