Canadian Journal of Pure & Applied Sciences

Abstract: In this study, ripe and mature females Labeo rohita (Hamilton) were sampled from Punjab University Research Fish Farms Lahore, in June and July 2009. Mean body weight and mean total length of fish was 559.20±175.31g and 35.04±3.27cm respectively. The mean ovary weight was 88.76±30.71grams. The ovaries were extracted, dried and weighed individually. Mean number of eggs/g ovary and number of eggs/g fish were 891.50±126.32 and 142.47±37.22 respectively. The mean absolute fecundity was 80290±32955 and mean relative fecundity was 142466±37226. These values were higher in June than in July sample. Two ovaries from fishes of same body weight (460g) contained different number of eggs (78876 and 75850). The highest value of gonadosomatic index (22.68) was recorded in June, indicating breeding and spawning period of L. rohita. Fish weight was significantly correlated to total length (r = 0.780) and ovary weight (r = 0.710). The relationship between fecundity and fish total length, fish weight, ovary length and ovary weight showed positive linear correlation and the correlation coefficient values for these relationships were 0.543; 0.698; 0.536 and 0.914 respectively. The fecundity of L. rohita of present stock was significantly correlated to fish total length and body weight; ovary length and ovary weight. However, the ovary weight is the most reliable and better index of fecundity than total length and weight of the fish.