نوع مقاله : مقاله پژوهشی
1 گروه شیلات، دانشکده علوم دریایی، دانشگاه دریانوردی و علوم دریایی چابهار، چابهار، سیستان و بلوچستان
2 گروه شیلات، دانشکده کشاورزی و منابع طبیعی، دانشگاه گنبد کاووس، گنبد، گلستان
عنوان مقاله [English]
This study was conducted to evaluate the effects of two commercial prebiotic and probiotic called Behsam and Behsil, respectively, in feeding performance, ammonia and urea excretions as well as energy losses in grass carp, Ctenophryngodon idella fry. Three levels of Behsam and Behsil (200, 400 and 600 mg/kgof diet) were supplemented to experimental diets and fed to grass carp fry (initial weight of 625.15 ± 10.12 mg). The present study was conducted in a completely randomized design. At the end of experiment, the fish final weight, food conversion ratio, protein and lipid efficiency ratio of the grass carps fed supplemented diet with different levels of Behsam and Behsil had significantly difference with control group (p<0.05). The results clearly exhibited that the different levels of Behsam and Behsil had positive effects on the ammonia and urea excretions in fish fry and also the energy decreasing rate in experimental treatments in comparison with control group. Minimum of ammonia-N and urea-N excretions were obtained in treatment Behsam 600. The maximum energy losses via excretion of ammonia and urea were obtained in control. However, the minimum energy losses were obtained in fish fry fed with 600 mg/kg Behsam. The total energy losses by nitrogenous wastes such as ammonia, urea and energy losses rate (%) per energy intake were decreased in the various experimental treatments in comparison with control. Maximum energy expenditure was detected in control group, but it decreased in experimental treatments and minimum value was obtained in treatment containing 600 mg/kg Behsam. In this study, it was found that the various Behsam and Behsil levels in rearing grass carp fry exhibit different effects on feeding performance, ammonia and urea excretions as well as energy losses in this fish.