Elżbieta Terech-Majewska, Joanna Grudniewska, Krzysztof Duchiewicz, Joanna Pajdak, Edyta Kaczorek, Patrycja Schulz, Andrzej K. Siwicki
ABSTRACT. Effective microorganism (EM) technology relies on microorganisms to enhance natural biological processes. In 1982, the EM concept was introduced to the world by Professor Teruo Higa of the University of the Ryukus in Okinawa, Japan. From among 2,000 beneficial microorganisms, Higa identified a combination of 81 microorganisms that are safe for human consumption. The EM-1 microbial inoculant is composed of lactic acid bacteria, photosynthetic bacteria, yeasts, Actinobacteria, and fermenting fungi. EM technology has been used extensively in 120 countries globally, and it is also growing in popularity in Poland, mainly in agriculture and aquaculture. It offers an alternative to antibiotics and crop protection chemicals. The EM concept is fully consistent with the principles of organic farming and the latest trends in the protection of human and animal health. Effective microorganisms are recommended for purifying ponds and even entire drainage basins. In this study, feed administered to the rainbow trout (200 fish per group) with an initial body weight of 30 g was supplemented with 2% of EM over a period of thirty days. The growth rate and the feed conversion ratio of the experimental fish were compared with the control group to which EM was not administered. Serum concentrations of Ig, total protein, lysozyme, and ceruloplasmin were determined in both groups. At the end of the supplementation period, the fish were infected intraperitoneally with a highly virulent strain of Aeromonas salmonicida (0.2 ml of bacterial suspension 1x105). Mortality rates caused by the experimental infection were lower in the group receiving EM. The results of the study indicate that EM supplementation enhances non-specific immune responses and reduces mortality in fish. However, the results showed considerable variation in the clinical course of infection, probably as a consequence of the diversity of immunological parameters.
Keywords: effective microorganism (EM) technology, rainbow trout, non-specific immunity, anti-infectious immunity
Przyjęto po recenzji 8.03.2016 r.