Studies on the histology and histopathology of the rainbow trout, Salmo gairdneri irideus. I. Hematology: Under normal and experimental conditions of inflammation
Weinreb, Eva Lurie
Zoologica new York 43(4): 145-154
In normal blood, using phase contrast microscopy, the predominant leucocyte is the lymphocyte, the heterophil is scarce, and eosinophils and basophils seen only occasionally. Turpentine produced a sterile inflammation, resulting in heterophilia, lymphopenia, and thrombocytopenia. Blood counts, made over a 72-hour period, revealed marked heterophilia at 6 hours due to release of myelocytes and meta-myelocytes. Cortisone, given concurrently and in advance of turpentine, reduced the inflammatory response, while advance injection also reduced mortality by almost 50%. Decrease in lymphocyte number appears to be in direct response to adrenal cortical stimulation initiated by ACTH. Heterophilia is not under direct adrenal cortical control, but subject to a wider range of influencing factors. The mechanisms of leucocyte control, as well as physiological response of each cell type, in the trout is comparable to that in mammals.