Vol. 1, Issue 12, Part O (2015)

Abstract
The present study relates the length-weight relationship, relative condition factor of fish species Heteropneustes fossilis (Bloch) of Deepar Beel, a Ramsar site of Assam. The fish is separated into male and female to compute length-weight relationship and relative condition factor separately. The correlation coefficient ‘r’ exhibits high degree of relationship of growth performance of length-weight relationship in both the sexes although the allometric growth shown by ‘b’ value is negative. The negative allometric growth observed may be due to lower feeding proficiencies and/or may be the environment or the season of experiment are not suitable for proper growth of fishes. Moreover, the growth so occurred may be the result of loss of energy for breeding purpose of the present study. The ‘b’ value being a constant for an ideal fish deviates significantly in male but slightly in female. The Kn value with more or less similar value in both the sexes show good general condition of the fish with more or less similar value in both male and female. The Kn value of male Heteropneustes fossilis ranges between 0.63 and 1.91 with an average of 1.08±0.37 where in female between 0.62 and 1.89 with an average of 0.99±0.21. In female the relative condition factor (Kn) increases from lighter to heavier, but in male declines initially from size range 5.41-7.15 cm TL, exhibit the minimum value at medium sized fish (11-12 cm TL) and thereafter steadily incline to get the maximum value in bigger fish having size range of about 17-18 cm TL.