Comparison on the effects of indigenous Lactobacillus plantarum and Lactobacillus rahmnosus separately and combined together in diet on immune system function of Cyprinus carpio

In this research, the effect of Lactobacillus plantarum and Lactobacillus rhamnosus bacteria isolated from the gut of the domestic fish (Tor grypus) on the immune response of common carp (Cyprinus carpio) were evaluated. For this purpose, 300 juvenile carps with average weight of 70 ± 11.5 gr were randomly divided into five groups and were fed with feed containing Lactobacillus plantarum, 5×107 CFU/ml Lactobacillus rhamnosus, bacteria combination, 250 mg of commercial product of Multi-Behsil probiotic and non-probiotic for 60 days, respectively. Blood samples were taken at days 0, 30 and 60 from each group and immunological parameters were analyzed and compared. All groups were challenged with Aeromonas hydrophila bacteria on day 60 of the experiment. The lysozyme activity in treated groups with rhamnosus, combination and commercial probiotic significantly increased compared with control group. The activity of myeloproxidase in commercial probiotic group had a significant increase on day 30. There was also a significant rise in NBT reduction in the combination and commercial probiotics group (p <0.05). The bactericidal activity in the plantarum and combination group on day 30 was significantly higher than control group. Bactericidal activity increased significantly after 60 days in all treated groups. Total immunoglobulin in combination and plantarumgroup rose significantly on days 30 and 60, respectively. After the challenge, the combination diet showed a better survival rate than other groups. The results showed that the two isolated bacteria had probiotic effects and appropriate immune stimulation, especially asmixture.