
The present study has been taken up in the Sidzii streams of Mao, Manipur, a tributary of Doyang River, the largest and longest river of Nagaland during December 2011 to November 2012. The highest Total Erythrocyte Count (TEC) value was observed in male Puntius sophore during October with a corresponding value of 2.23x106/mm3 of blood while the lowest value was recorded in female Parluciosoma daniconius during February with the value of 1.12x106/mm3 of blood. Among the female fishes, highest TEC value was recorded in Puntius ticto with the value of 2.18x106/mm3 of blood during October while the lowest value was found in Parluciosoma daniconius during May. Again, in male fishes, the maximum TEC value was observed in Puntius sophore with the value of 2.23x106/mm3 of blood during October and minimum TEC was recorded in Parluciosoma daniconius with the value of 1.17x106/mm3 of blood during February. In all the four seasons, male fishes have comparatively more TEC values than their female counterparts. However, in July, the TEC value were found to be higher in females of Puntius sophore and Puntius ticto with the corresponding values recorded as 1.54x106/mm3 and 1.59x106/mm3 of blood respectively. It was also observed that the higher TEC values for all three species were recorded during post-monsoon as compared to the other seasons.