Determantion of Growth Parameters, Digestibility and Nitrogen-Phosphorus Enviromental Impacts of Enzyme Supplementation to Soybean Based Diet in Rainbow Trout (Oncorhynchus mykiss)

Abstract

This study was carried out to determine the effects on growth performance, feed utilization, apparent digestibility and reduce environment pollution waste output of nitrogen and phosphorus of diets based on Soybean Meal (40%) supplemented with exogenous enzymes in rainbow trout (Oncorhynchus mykiss) culture. Trout groups was began (initial mean weight 87.00±1,5g) method of random plots with 3 replications of 50 fish/pond with the ratio of 1050 fish with 6,0 metrik tonne in concrete ponds. 43% protein - 12% fat diet was used as the with no added enzyme in control group (K0) and diet supplemented with %02 protease enzyme (P), %02 mix enzyme (cellulose, xylanase, endo-s-1,3:1,4-glucanase (M), %02 pyhtase enzyme (F), %01 protease + %02 mix enzyme (PM), %01 protease + %01 phytase (PF) and %01 mix enzyme + %01 phytase (MF) were tested in total 7 groups. About of growth performance were found while condition factor (1,21-1,23) were statistically similar (p>0.05) however growth rate (173,68-177,27), specific growth rate (1,118-1,340) and feed conversion ratio (1,26-1,30) significantly different among groups (p<0.05) at the end of the experiment. P and F groups significantly improved specific growth rate, feed conversion ratio better than control group. In this study, showed the highest nitrogen apparent digestibility coefficient (ADC-N) (85,49±1,98) in group of P while the poorest value (72,82±0.01) group of K0 obtained, respectively (p<0.05). Also the best (58.57±0.49) and lowest (42.85±1.98a) ADC-P for phosphorus was obtained from F and K0, respectively (p<0.05). The highest (53,71%) and lowest (17,69%) retained nitrogen was held in the P and K0 groups (p<0,05). Also the dropped to water (discarded), nitrogen effluent was lowest (23,31 g/kg) in the P group and highest (46,91 g/kg) in the K0 group, respectively (p<0,05). In addition, highest (68,74%) and lowest (46,12%) retained phosphorus levels were obtained in the F and K0 groups, respectively. Also the dropped to water (discarded) while phosphorus levels reached the maximum (6,.94 g/kg) in K0 group and minimum value was obtained in the F group (4,85 g/kg)(p<0,05).