nimai chandra saha

In the present study a trial for induced breeding of a minor bagrid Mystus vittatus was made by stripping methods using various doses (0.2, 0.3, 0.4,0.5, 0.6 and 0.7 ml/kg body weight) of a synthetic hormone, Ovasis at 26, 28 and 30ºC to evaluate their breeding performance. During spawning their latency period ranged between 12-17h. Highest number of absolute fecundity (3785 nos.) and relative fecundity (209.04 nos./g) were recorded at the dose of 0.5 ml/kg body weight of female at 28ºC. Similarly highest breeding success was observed at this dose and temperature when female was bred with male counterpart treated with a dose of 0.2 ml/kg body weight. In this condition the rate of fertilization and hatching of eggs were 84.15% and 75.48% respectively. Lowest breeding performance was recorded at the dose of 0.7 ml/kg body weight of female at 26ºC. Further, the developmental stages of fish (fertilized egg to 28thday old fish) were also characterized chronologically along with their behavioral tendency in this study. Morphological deformities of 6.3% was recorded at 26ºC in the hatchlings developed from the eggs under the administration of dose of 0.7 ml/kgbody weight. Recommended dose of ovasis is 0.5ml/kg of Mystus vittatusat 28ºC.