Effects of dietary prebiotic Immunogen on the compensatory growth and some hematological parameters in koi carp (Cyprinus carpio var. Koi), after starvation period

This study aimed to determine the effects of dietary prebiotic Immunogen on the compensatory growth of koi carp (Cyprinus carpio) fingerlings (n= 300; 3.60 ± 0.12 g), following one-week starvation. The experiment was conducted within 60 days with three treatments. In treatment C, fish were fed with non-prebiotic diet and with no starvation period, while in treatment G1, fingerlings starved for one week then fed with 2.0 g of Immunogen per kg diet, and in G2, fingerlings received no prebiotic following one-week starvation. The results showed that the highest final weight and specific growth rate (SGR) were observed in the control followed by G1 (P<0.05). The lowest feed conversion ratio (FCR) was recorded in treatment C. Numbers of red blood cells were similar in all treatments (P>0.05). Hemoglobin and hematocrit were maximum in C. G1 contained the highest number of white blood cells (WBC) (13690±550). In WBC differential counts, significant differences were observed only in neutrophils and lymphocytes (P<0.05). The minimum number of neutrophils and the maximum number of lymphocytes were observed in G1. Based on the results, although the addition of 2.0 g of prebiotic Immunogen in the diet of koi carp fingerlings could not improve their growth performance, it could give rise the better results compared with G2 which fed with no prebiotic after starvation. Furthermore, the fingerlings in G1 showed the best results in terms of immunity.