Abstract: Effect of oral immunization of Koi fry with inactivated Edwardsiella tarda and Aeromonas hydrophila during early development on non-specific immunological function of juvenile Koi was studied. The result showed that among juvenile Koi fed with inactivated bacteria since the seventh day after hatching,only head kidney weight index in A. hydrophila test group was no remarkable difference with control group(P 0. 05) ,head kidney weight index and spleen weight index in other test groups were obviously higher than control group(P 0. 05) ,phagocytic index of white cell in A. hydrophila test group was highly significantly higher than control group(P 0. 01) ,the activities of SOD in serum of all test groups were obviously stronger than control group(P 0. 05) . Among juvenile Koi fed with bacteria since the thirty-second day after hatching,head kidney weight index in all test groups were not obviously difference with control group(P 0. 05) ,spleen weight index in E. tarda test group was higher than control group (P 0.05) ,phagocytic percent and index of white cell in blood were highly significantly higher than control group (P 0.01) ,the activities of LZM in serum of test groups were highly significantly stronger than control group (P 0.01) ,the activities of SOD in serum of E.tarda test group(P 0.05) and A.hydrophila test group(P 0.01) were stronger than control group. Non-specific immunological function of juvenile Koi could be promoted by taking inactivated E. tarda and A. hydrophila orally in an early period of development.

Key words: Edwardsiella tarda, Aeromonas hydrophila, Juvenile Koi, Non-specific immunological function

CLC Number: 

• S942.