Introduction of some serum, immunity and blood indices as health indicators in rainbow trout (Oncorhynchus mykiss) brood stock of specific pathogen free fish (SPF)

In this study has been attempted to evaluate some hematological, serological and immunological indices to determine the baseline for determining the health of SPF brood stock. For this purpose, during three sampling stages, before, simultaneously and after breeding time, the blood samples were collected from brood stock fish at the SPF center in the Cold water fisheries research Center (Tonekabon) and two elected farms (F and S). The fish of SPF center were supplied of the two others farms (F and S) and sampling were conducted from same folk at the SPF center and elected farms. Hematocrit, hemoglobin, total protein, albumin, alanine aminotransferase (ALT), aspartate amino transferees (AST), certain phosphokinase (CPK), alkaline phosphatase (ALP), total IgM and lysozyme were measured. The results showed that before the breeding season, the levels of hemoglobin, ALT and total IgM were not significantly different among the fish in the three centers, but the lysozyme levels of SPF center were significantly and numerically higher than S and F fish farms respectively. Statistical analysis of data showed that there were no significant differences in hematocrit, hemoglobin, total protein, albumin, IgM, AST, ALT and lysozyme levels among the three groups during the breeding season. The results after the breeding season showed that the hematocrit and weight of SPF fish were significantly higher than those two other groups but  hemoglobin, IgM and lysozyme levels were significantly and or numerically higher than those two other groups. Based on the results, it seems that the use of blood and serum indices can be used as a tool for health assessment condition, nutrition, rearing and hygiene managements. It seems that the health and nutrition management of the SPF center had been better than two other farms and it caused to improve the hemato- serological and immunological parameters of the SPF fish in compared to the other elected farms fish after breeding time.