Regarding to measure some hematological factors of Caspian Salmon (Salmo Trutta caspius), 55 immature and 21 mature individuals were studied. The main results were: Immature Mature - Hemoglobin value (gr/dl) 7.20 9.87 - Hematocrit 34.1 39.2 - Mean No. of red blood cells (per mm3) 934300 1306200 - Mean No. of white blood (per mm3) 8380 6219 - Mean No. of platelets (per mm3) 21180 13159 As the results showed the number of white blood cells and platelets in immature individuals were more than mature specimen. The obtained results of blood indices were as follow: Immature Mature - Mean MCV (FL) 385.4 302.9 - Mean MCH (Pg) 82.0 75.5 - Mean MCHC (%) 21.6 25.6 - Lymphocyte (%) 96.1 69.9 - Neutrophil (%) 3.4 29.4 - Monocyte (%) 0.52 1.14 Notice: Eosinophil and basophil cells weren't observed
