Abstract
Spawning biology of hormone induced bagridae catfish, Mystus dibrugarensis was observed in captive condition. Active involvement of male in courtship after 5-9 hr. of hormone administration was observed. Different doses of ovaprim 0.4, 0.6, 0.8, 1.0 ml/kg were used by maintaining 1:1, 2:1 and 3:1 ratio of M:F. All female successfully bred in all the condition in more or less amount. Overall 24.5-77.5% fertilization and 12-76% hatching rate was observed. However, considering the rate of fertilization, and hatching success in the present case, at 0.8 ml/kg body weight and sex ratio 2♂: 1 ♀ seems ideal for induced breeding of M. dibrugarensis. Apart from induced breeding certain reproductive aspects were also studied in the present experiment.