نوع مقاله : مقاله پژوهشی
گروه شیلات، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه سرا، گیلان
عنوان مقاله [English]
This study was conducted to investigate the effects of dietary betaineon fecundity, fertilization, hatching, larvae survival rates and interval times among continuous spawning in the Golden Severum, Heros severus. For this purpose, three experimental diet treatments were applied to Severum brood stocks as follow: an ornamental commercial diet without betaine (control diet), the commercial diet with 5g betaine per kg food (treatment 2) and the commercial diet with 10g betaine per kg food (treatment 3). Four replicates were used in this trial. In this study, 12 pairs of spawning Severum fish has been kept in 12 aquariums with 50 liters volume, in 28 ± 1°C. Feeding were two times a day. The highest fecundity with average of 655.4 eggs were observed in treatment 3 and the highest hatching rate and larval survival rate respectively 98.79 and 94.58 were observed in treatment 2 which were significantly different from the control (P≤0.05). The shortest interval times between continuous spawning with average of 7.31 days was observed in treatment fed with 5g betaine per kilogram diet which was significantly different from the other treatments. In summary, it can be concluded that using betaine with 5 g per kg diet can make a positive increasing in reproductive performance in Severum fish.