عنوان مقاله [English]
This study aims to investigate the effect of vitamin C with in the diet plan of Cyprinus carpio (Koi fish) will result in positive outcomes on the survival, growth performance and hematological parameters of these particular breeds. The purpose of this paper was to increase the production performance of ornamental fish species in the aquaculture with the aim to keep the time and costs to a minimum. In order to achieve these results, the author framed an experiment on 144 Koi fishes in four different groups (one control group and three treatment groups). Later on, all the four groups were fed with vitamin C rich diet (with the doze of, 200, 400, 600 mg per kg of dried ration) for two month. The biometric juveniles (total length and standard weight) of the subjects were measured every 14 days. Moreover, the calculation of growth rate, hematological rates and feeding the subjects were performed at the end of a two month time period. Results showed that addition of vitamin C in diets caused an increase in weight, in control group, whose diets were without vitamin C became in average 1.58 g, treatment 1 in average 1.73 g, treatment 2 in average 2.13 g and treatment 3 in average 4.4 g and increasing weight among groups had significant differences. Survival rates in control group was in average 84%, in treatment 1, 95%, in treatment 2, 95% and in treatment 3 was 97%, but there were no significant differences among groups. In studied fish we faced with increasing percentage of body weight of 39.71% in treatment 3 which has no significant differences with other groups. The most growth rate was assessed in treatment 3 (0.58) and it had significant difference with the control group only. Protein Efficiency Ratio in treatment 3 was in average 2g and it had no significant difference with other groups. There were no significant differences among these groups in number of white blood cells and the most number of white blood cells was assessed in control group.The number of lymphocytes were increased by the increase in the amount of vitamin C and the highest amount was reached in treatment 3, which was 70, but there was no significant difference in number of lymphocytes among groups. Finally based on results in present research, vitamin C with concentration of 600mg in kg in dry diets is recommended for increasing growth performance and hematological parameters in Koi fish.