Determination of Hematological and Biochemical Parameters of Rainbow Trout (Oncorhynchus mykiss) Affected with Streptococcosis Subsequent Use of Bacillus subtilis as probiotics

In this study Bacillus subtilis wass used to control streptococcosis caused by Streptococcus iniae in rainbow trout. The experience was carried out in 2 groups (control and treatment) and 3 replicates. In control group, probiotic was not applied in diet and in test groups, Bacillus subtilis was administered in feed at a concentration of 107 cells per gram. In the day of forty five, 0.1 ml intraperitoneally injection of S. iniae with 2×107 cells ml-1 dosage was done for both of groups and were checked for the rest of the survey duration (2 weeks). At the end of the time which took about two months, 5 blood samples were caught for hematological and biochemical experiments from every replicate for realizing the effect of B.subtilis feeding on resistance of fish against S. iniae infection. Significant difference was seen in the leukocyte count, percent of lymphocyte and neutrophile, serum total protein, serum albumin, IgM and lysozyme in both groups (P<0.05). The leukocyte count, percent of lymphocyte, serum total protein, serum albumin, IgM and lysozyme were higher in T group and neutrophil percent was lower in comparison with the control