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In order to study the morphology of bone marrow cells and MIE ratio, bone marrow, and peripheral blood samples were collected from 30 Iranian native cows of both sexes and in different ages.
Bone marrow samples were collected from sternum and peripheral blood was collected from jugular vein. Samples were stained with Wright's and Giemsa techniques. Morphological and morphometric results of this study indicated that:
1 - Development and formation of the hematopoietic cells in the native Iranian native cows were similar to the other mammals.
2 - Age and sex had a significant effects on the percentage, size of the hematopoietic cells and M/E ratio (p<0.05). MIE ratio increased from birth to the maturation and dl2creased in aging and in females was lower than males.
3 - In the present study, there were no significant differences in the percentage of peripheral blood leukocytes of male and females and also in
diftrrent age groups (p>0.05).