Abstract

• The study was conducted to elaborate the reproductive aspects, including sex ratio, condition factor, GSI, fecundity and correlation between fecundity and standard length, body weight and ovary weight in Mystus cavasius from Ayeyawady River Segment, Magway Township during December2018 to August 2019. A total of 78 males and 102 females contributing 1: 1.31 sexratios were presented. Mean standard length and mean body weight of collected fish samples were 10.39 to 11.86cm, 15.82 to 22.51 g and 10.06 to 12.68cm, 16.3 to 31.38g for male and female fish respectively. Condition factor (K) values ranged from 1.13 to 1.53 in male and 1.21 to 1.43 in female. The gonadosomatic index was calculated to be 0.059 to 0.22 and 0.57 to 12.33 respectively for male and female. The highest GSI 0.22 in May (male) and 12.33 in July (female) were observed. The absolute fecundity ranged from 4856 to 58889.5 eggs with the mean 27437.9±18193.4 for the corresponding length of 12.07±1.9cm, body weight of 27.57±11.28g and ovary weight of 3.86±2.5g. Relationships between standard length and body weight, were positively correlated in both sexes. Absolute fecundity was positively correlated with standard length and body weight whereas it was strong positively correlated with ovary weight.